    [From the U.S. Government Printing Office, www.gpo.gov]

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                                                                                       The Federal Interagency Floodplain Management Task Force was established
                                                                                       in 1975 to carry out the responsibility of the President to prepare for the Con-
                                                                                       gress a Unified National Program for Floodplain Management. Since 1982
                                                                                       the Task Force has been chaired by the Federal Emergency Management
                                                                                       Agency. Membership of the Task Force consists of the Departments of
                                                                                       Agriculture, Army, Commerce, Energy, Housing and Urban Development,
                                                                                       Interior, and Transportation; the Environmental Protection Agency; and the
                                                                                       Tennessee Valley Authority.

                                                                                                                            -7-

                 Design: Mike Campbell, Publications Department,
                 Unzversi@y of Colorado.
                 Coverphoto: Bob Cox, Floodplain Management Section,
                 Louisiana Department of Transportation
                 and Development.

                              FLoODPLAIN MANAGEMENT

                                       IN THE

                                   UNITED STATES:

                               ANAsSESSMENTREPORT

                                       Volume 1
                                       SUMMARY

                                       Prepared for
                                   The Federal Interagency
                                   Floodplain Management
                                       Task Force

                                       Prepared by
                                    The Natural Hazards
                                   Research and Applications
                                     Information Center,
                                 University of Colorado at Boulder

                                   (Contract No. TV-72105A)

                                         1992
                                 VzWerty of CSC Librmy

      J
                              US Department of commerce
                              NOAA Coastal Services Center Library
                              2234 South Hobson Avenue
                              Charleston, SC 29405-2413
          ca

                                                                                                  Contents

                                                                 Preface  .........................................................           4
                                                                 Acknowledgments     ................................................         5

                                                                 Part 1: The Nation's Floodplains, Their Value, and Their Floods
                                                                 Floodplains  ......................................................          8

                                                                 The Value of Floodplains    ..........................................       8
                                                                    Water Resources    ...............................................        9
                                                                       Flood and Erosion Control   ....................................       9
                                                                       Surface Water Quality Maintenance     ............................     10
                                                                       Groundwater Supply and Quality     ..............................      10
                                                                    Living Resources   ..............................................         10
                                                                       Wetlands   ..................................................          10
                                                                       Riparian Systems   ...........................................         11

                                                                    Cultural Resources  ............................................          12

                                                                 Floods   .........................................................           13
                                                                    Riverine Flooding   .............................................         13
                                                                    Flooding from Surface Runoff   ...................................        14
                                                                    Coastal Flooding and Erosion   ...................................        14
                                                                    Ground Failure    ...............................................         15
                                                                    Fluctuating Lake Levels   ........................................        16

                                                                 Floodplain Losses  ................................................          16
                                                                    Loss of Life and Property   ...............  I .......................    18
                                                                    Loss of Natural and Cultural Resources    ...........................     19

                                                                 Part 11: Managing Floodplains to Reduce Losses
                                                                 The History of Floodplain Management      .............................      24
                                                                    1900-1960: The Structural, Federal Era   ............................     24
                                                                    1960s: A Time of Change     .......................................       24
                                                                    1970s: The Environmental Decade      ...............................      26
                                                                    1980s: Continuing Evolution   ....................................        26

                                                                 The Management Framework        .....................................        26
                                                                    The Federal Government      .......................................       28
                                                                    State Government    .............................................         28
                                                                    Local Government    ............................................          29
                                                                    Regional Entities  ..............................................         29
                                                                    The Private Sector  ............................................          30

                                                                 Modifying Susceptibility to Damages and Disruption      ..................   30
                                                                    Regulations   ..................................................          30
                                                                    Development and Redevelopment Policies      .........................     32
                                                                    Disaster Preparedness   ..........................................        32
                                                                    Flood Forecasting, Warning, and Emergency Plans      ..................   33
                                                                    Floodproofing and Elevation   ....................................        33

                                                                 Modifying Flooding    ..............................................         34
                                                                    Investment in Flood Control   ....................................        35
                                                                    Dams.and. Reservoirs . . .,. I......................................      36
                                                                          '  L@      -d Floodwalls ...................................        37
                                                                    Dil@@s,'Levees, an
                                                                    Channel Alterations   ...........................................         38
                                                                    High Flow Diversions    ..........................................        38
                                                                    Stormwater Management       .......................................       38
                                                                    Shoreline Protection  ...........................................         38
                                                                    Land Treatment Measures     ......................................        39

               Modifying the Impacts of Flooding    .................................        40
                 Information and Education     .....................................         40
                 Flood Insurance    ..............................................           40
                 Tax Adjustments    ..............................................           42
                 Flood Emergency Measures      .....................................         43
                 Disaster Assistance   ............................................          43
                 Postflood Recovery    ............................................          45

               Restoring and Preserving the Natural and Cultural
               Resources of Floodplains   ..........................................         45
                 Regulations    ..................................................           46
                 Development and Redevelopment Policies        .........................     47
                 Information and Education     .....................................         48
                 Tax Adjustments    ..............................................           48
                 Administrative Measures     .......................................         49

               Part III: The Effectiveness of Floodplain Management
               Perception and Awareness of Floodplain Losses     .......................     52
                 Recognition of Risk    ...........................................          52
                 Awareness of the Value of Natural Floodplains     ......................    53

               Knowledge, Standards, and Technology      ..............................      54
                 Climate Change and Weather Forecasting        .........................     54
                 Streamflow Data    ..............................................           54
                 Hydrology and Hydraulics      ......................................        54
                 Flood Forecasting and Warning      ..................................       55
                 Soil Identification and Mapping    .................................        55
                 Mapping Flood Hazards       .......................................         56
                 Understanding and Mapping Wetlands         ...........................      57
                 Understanding Natural and Cultural Resources        ....................    57
                 Remote Sensing Techniques     .....................................         57
                 Geographic Information Systems     .................................        57
                 Regulatory and Design Standards      ................................       58

               judicial Support for Floodplain Management      .........................     58
                 Constitutionality of Regulations   ..................................       58
                 Liability for Flood Damages   .....................................         59
                 Avoiding Legal Problems     .......................................         59

               The Present and the Future    .......................................         60
                 Overview    ....................................................            60
                    Overall Effectiveness   ........................................         60
                    Achievements to Date     .......................................         60
                    The Need for Specified Goals    .................................        61
                    The Need for a Comprehensive Data Base        .................... .     61
                 The Effectiveness of Management      ................................       61
                    Allowing for Different Approaches     .............................      61
                    Coordination Among Government Agencies          .....................    62
                    Providing for Local Conditions    ................................       62
                 The Effectiveness of Floodplain Management Strategies and Tools        ..... 63
                    Modifying Susceptibility to Flood Damage and Disruption        ......... 63
                    Modifying Flooding     .........................................         63
                    Modifying the Impact of Flooding on Individuals
                       and the Community     .......................................         64
                    Restoring and Preserving the Natural and Cultural Resources
                       of Floodplains  ............................................          64

               Conclusion   .....................................................            65
               Retrospect and Prospect
                    -Gilbert F White   ............................................          67

                                                                                                         Preface

                                                                     The coastal and riverine floodplains of the United States are highly desirable
                                                                     and rewarding sites for most kinds of human activities and contain a wealth
                                                                     of natural and cultural resources of immense importance and value to the
                                                                     nation. Yet they are the source of costly and frequently unnecessary losses of
                                                                     human life and property as well as losses of resources afforded by floodplain
                                                                     environments.
                                                                          In terms of areas affected and annual economic losses, flooding remains
                                                                     the greatest and most persistent natural disaster facing our nation, despite
                                                                     concerted efforts at all governmental levels and within the private sector to
                                                                     moderate, account for, or adjust to the flood risk. These efforts go back at
                                                                     least to the turn of this century, when initially they were focused on control-
                                                                     ling the paths of flood waters. Other flood loss reduction strategies and a
                                                                     myriad of programs have since evolved to complement these initial efforts.
                                                                     More recently, increased attention has been given to preserving the natural
                                                                     functions and resources of floodplains.
                                                                          This assessment of floodplain management in the United States was
                                                                     commissioned in 1987 by the Federal Interagency Floodplain Management
                                                                     Task Force. Its purpose was to provide an evaluation of floodplain manage-
                                                                     ment activities in order to report to the public and to the Congress on pro-
                                                                     gress toward implementation of "A Unified National Program for Floodplain
                                                                     Management" [Section 1302(c) of the National Flood Insurance Act of 1968].
                                                                     Thus, it is a compilation of available information concerning the nation's flood-
                                                                     plains, experience with tools and strategies to reduce losses of life, property,
                                                                     and environmental resources, and a perspective of what has been
                                                                     accomplished.
                                                                          The assessment is presented in two parts. This summary report (Vol-
                                                                     ume 1) presents the salient information and findings of the full report (Vol-
                                                                     ume 2) and reflects both its content and organization. Sources of information
                                                                     for Volume 1 and additional detail, explanation, and analysis can be found in
                                                                     the full report.
                                                                          A concerted attempt was made to compile information and available
                                                                     data from numerous sources in an attempt to describe, evaluate, and provide
                                                                     for a balanced view and account of the various activities and management
                                                                     approaches. However, all accounts and contributions to floodplain management
                                                                     may not be adequately documented in this assessment due to the lack of suffi-
                                                                     cient information or usable data regarding certain subjects or topics. Never-
                                                                     theless, task force member agencies concurred with the content of this docu-
                                                                     ment and believe that this assessment provides the most comprehensive
                                                                     statement available and a foundation for action to improve effectiveness of
                                                                     floodplain management in the United States. It is commended to all parties
                                                                     who make decisions affecting floodplains and their occupants and to those
                                                                     having an interest in learning more about this subject.

                                                                     Frank H. Thomas
                                                                     Federal Emergency Management Agency
                                                                     Chair, Federal Interagency Floodplain Management Task Force

               4

                                         Acknowledgments

               This summary was prepared under the direction of the Natural Hazards
               Research and Applications Information Center, University of Colorado at
               Boulder, and is based on the full report prepared by L.R. Johnston Associ-
               ates. Both reports resulted from contractual arrangements with the Tennessee
               Valley Authority, which managed the national assessment effort for the Inter-
               agency Task Force. Principal authors of the two reports were Jacquelyn L.
               Monday and the late Larry R. Johnston, respectively.
                    Countless others contributed support, information, and ideas. The
               Federal Interagency Floodplain Management Task Force provided funding
               for this study, and an Advisory Committee of the Task Force was created to
               provide direction and guidance throughout the work effort, including review
               of draft reports. The Association of State Floodplain Managers and the Asso-
               ciation of Wetland Managers devoted a portion of their annual conferences to
               provide information and input to the process. A National Review Committee,
               comprised of recognized experts and chaired by Gilbert F. White (one of the
               true pioneers of the floodplain management movement that began around
               50 years ago) added valuable insight and proposed an Actw'n Agenda. Many
               individuals, including those representing government agencies and profes-
               sional and nonprofit organizations, also made important contributions by
               providing information, data, insights, and perspectives.

               James M. Wright
               Tennessee Valley Authority
               Project Manager

                                                                                                                                               5

                          PART I

                TFIENAT.iON@s FLoODPLAINS,
                       THEIR VALUE,
                     ANDTHEIRFLOODS

                                                                                                  Floodplains

                                                                   Floodplains are the lowlands adjoining the channels of rivers, streams or
                                                                   other watercourses, or the shorelines of oceans, lakes, or other bodies of stand-
                                                                   ing water. They are lands that have been or may be inundated by flood water.
                                                                   Floodplains are shaped by dynamic physical and biological processes: climate,
                                                                   the hydrologic cycle, erosion and deposition, extreme natural events, and
                                                                   other forces. The products of the complex interrelationships of these processes
                                                                   are many of the nation's most beautiful landscapes, most productive wetlands,
                                                                   and most fertile soils, along with rare and endangered plants and animals, and
                                                                   sites of archaeologic and historic significance. Throughout our history, rivers
                                                                   and other bodies of water have been highways for exploration, migration, and
                                                                   commerce and have been used as disposal systems for the byproducts of indus-
                                                                   trial society. Almost all major cities are located on a river or at the mouth of
                                                                   a river. Most smaller communities have at least one stream that helps define
                                                                   local character and is an important source of community identity.

                                                                                       The Floodplain with Floodway

                   FLOODPLAIN MANAGEMENT
              Floodplain Management is a decisionmaking
              process the goal of which is to achieve wise use
              of the nation's floodplains. "Wise use" is any
              activity or set of activities that is compatible with
              the risk to natural resources (natural and henefi-
              cialfunctions offloodplains) and human
              resources (life and property). Compatibiliy is
              acheived through the strategies and tools of the                                  Floodway
              Unified A7ationol Program for Floodplain                       Flood Fringe                        Flood Fringe
              Mana ement.
                   9

                                                                                          1 00-Year " Floodplai n

                                                                             Flood Fringe      Floodway          F.1ood Fringe    a

                                                                                                           Channel

                                                                        The U.S. Water Resources Council estimated in 1977 that about 7%, or
                                                                   178.8 million acres, of the total area of the United States, including Alaska and
                                                                   Hawaii, Puerto Rico, and the Virgin Islands, was within the 100-year flood-
                                                                   plain. The Federal Emergency Management Agency, in a 1991 study that
                                                                   examined nearly 17,500 mapped floodprone communities in the 50 states and
                                                                   the District of Columbia, estimated that there are about 94 million acres. The
                                                                   largest areas of floodplain are in the southern part of the country, but the
                                                                   most populous are along the north Atlantic coast, in the Great Lakes region,
                                                                   and in California.

                                                                                      The Value of Floodplains

                                                                   In their natural state, floodplains have enormous but often unrecognized
                                                                   value. These complex dynamic systems contribute to the physical and bio-
                                                                   logical support of water resources, living resources, and cultural resources.
              Previous page. The Yellowstone River and Hayden Valley Floodplains are important to the nation's water resources because they pro-
              in Yellowstone National Park are a river andjbodphin vide natural flood and erosion control, help maintain high water quality, and
              relatively undisturbed by hurnan intrusion.          contribute to sustaining groundwater supplies. Floodplains have living, or bio-
                                                                   logic, resource value, because they support a wide variety of flora and provide
              8

                 habitat for fish and wildlife. The cultural resources of floodplains include the
                 .maintenance of a harvest of natural products, places for recreation, scientific
                 study, and outdoor education, and sites of historic and archeological interest.
                       Although the value of these resources is now well recognized                ,and most
                 of the processes contributing to them reasonably well understood, it has proven
                 difficult and sometimes impossible to assign economic values to the functions
                 served and benefits provided by floodplains.

                                                      Water Resources
                       Water can be put to human use either while it is in the stream or other
                 water body or when it is diverted and used elsewhere. Offstream, surface
                 water can be used for irrigation, for industrial and municipal purposes, and
                 energy production. These uses reduce the flow or level of water, at least tem-
                 porarily, and inevitably degrade its quality somewhat. Instrearn uses of water
                 include navigation, fish and wildlife propagation, waste transport, hydropower                              Coastal barriers are constantly changing landjorms. They
                 generation, agricultural and industrial uses, recreational activities, and sup-                             protect much of the Atlantic and Gu@f coast from the direct
                 plying drinking water. Instream uses usually require a minimum flow or                                      effects of htgh water waves, currents, and severe storms.
                 water level and hence tend to compete with offstrearn uses.                                                 Development on a coastal barrier, Grand Isle, Louisiana.

                 Flood and Erosion Control
                       Natural, unaltered floodplain systems can reduce flood velocities, reduce
                 flood peaks, and reduce wind and wave impacts because their physical charac-
                 teristics affect flood flows and, typically, provide space for the dispersal and
                 temporary storage of flood waters until the natural drainage can carry them
                 away. This natural function obviously can reduce the potential damages and
                 loss of life from floods. One acre of a floodplain can store about 325,000
                 gallons of water if flooded to a depth.of only one foot. Floodplain vegetation,

                              Natural and Cultural Resources of Floodplains

                                                        Water Resources

                    Natural Flood and Erosion Control             Surface Water Quality Maintenance
                    � Reduce flood velocities                     0 Reduce sediment loads
                    � Reduce flood peaks                          * Filter nutrients and impurities
                    � Reduce wind and wave impacts                0 Process organic and chemical wastes
                    � Stabilize soils                             0 Moderate temperature of water
                                                                  0 Reduce sediment loads

                    Maintain Groundwater Supply and Quality
                    0 Promote infiltration and aquifer recharge
                    0 Reduce frequency and duration of low flows;
                       i.e. increase/enhance base flow

                                                        Living Resources
                    Support Flora                                 Provide Fish and Wildlife Habitat
                    0 Maintain high biological produc-            0 Maintain breeding and feeding grounds
                       tivity of floodplain and wedand            * Create and enhance waterfowl habitat'
                       vegetation                                 * Protect habitat for rare and
                    0 Maintain productivity of natural               endangered species
                       forests
                    0 Maintain natural crops
                    0 Maintain natural genetic diversity

                                                       Cultural Resources
                    Maintain Harvest of Natural and               Provide Opportunities for Recreation
                    Agricultural Products                         0 Provide areas for active and
                    0 Create and enhance agricultural lands          consumptive uses
                    0 Provide areas for cultivation of fish       9  Provide areas for passive activities
                       and shellfish                              0 Provide open space values
                    0 Create and enhance forest lands             0  Provide aesthetic values
                    0 Provide harvest of fur resources

                    Provide Areas for Scientific Study and Outdoor Education
                    � Provide opportunities for ecological studies
                    � Provide historical and archaeological sites

                                                                                                                                                                                 9

                                                                                          especially in wetlands, can reduce erosion by binding the soil with its root sys-
                            WETLAND FLOODPLAINS                                           tems. Moreover, friction between the vegetation and the water dampens waves
                      HELP MAINTAIN WATER QUALITY                                         and reduces current velocity. Coastal barriers- elongated, offshore formations
                                                                                          of sand and other unconsolidated sediments lying generally parallel to main-
                   0 Studies of heavio polluted watersflowing through                     land coastlines- protect large portions of the coast, including estuaries, bays,
                   Tinicum Marsh in Pennsylvania have revealed sig-                       and wetlands, from the direct effects of high water, waves, and currents
                   nz)'icant reductions in biological oxygen demand,                      caused by both normal and storm conditions.
                   phosphorous, and nitrogen within three tofive hours.
                   0 The value of Georgia's 2,300-acre Alcovy River                       P_41;.77  w`-
                   Swamp for water pollution control has been esti-
                   mated at $1 million ayear. The bottoinlandforested
                                                                                                CA
                   wedands along the river have been shown to filter
                                                                                                                                                                                                       V
                   impurities from flood waters.
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                                                                                          Floodblains and wetlands not only help  maintain water qualiy, they also provide a natural environment for
                                                                                          diverse species.
                                                                                          Bottomiand hardwood swamp, Louisiana.

                                                                                          Surface Water Quality Maintenance
                                                                                                 Natural floodplains can reduce the cost of waste water treatment and
                                                                                          water quality maintenance; they can reduce sediment loads, process chemical
                                                                                          and organic wastes, and reduce nutrients, thereby protecting the physical, bio-
                                                                                          logical, and chemical integrity of water. Floodplains buffer rivers, streams,
                                                                                          lakes, and estuaries from upland sources of pollution.

                                                                                          Groundwater Supply and Quality
                                                                                                 Conditions beneath undisturbed floodplains can facilitate the infiltration
                                                                                          and storage of water, permit groundwater recharge, purify water entering the
                                                                                          aquifer, reduce flood peaks, and ameliorate the frequency and duration of low
                                                                                          flows in groundwater systems. These functions help maintain and improve
                                                                                          conditions for municipal and private wells, wildlife, irrigation, and watering
                                                                                          livestock during drought.

                                                                                                                                   Living Resources
                                                                                                Floodplains are among the most productive of the planet's ecosystems.
                                                                       Q                  Because of their relative abundance of water, they provide habitat for a mul
                                                                                          titude of plant and animal species, and the energy and nutrients from their
                                                                                          healthy function are passed along to organisms in adjacent and down
                          4,_                                                             stream areas.

                                                                                          Wetlands
                                                                                                Wetlands are perhaps the most prominent and familiar of floodplain
                                       J                                                  resources. They are lands transitional between terrestrial and aquatic systems
                                                                                          and   are covered by shallow water or have a water table at or near the surface.
                                                                                          T
                                                                                            here are slightly in excess of 100 million acres of wetlands in the 48 con-
                                           OQ0                                                         ates, and the majority of these are in floodplains. Florida, Loui-
                                                                                          tiguous st
                                          x
                                                                                          siana, and Alaska have the most wetland acreage.
                   Rzparion habitats sustain ecosystems that include many                       Wetlands are classified by the U.S. Fish and Wildlife Service according to
                   large mammals such as bear, white-tailed deer, and                     five ecological systems, of which estuarine and palustrine wetlands are best
                   caribou.                                                               known. Estuarine systems include such coastal wetlands as salt and brackish
                   White-tailed deer, St. Andrews Bay, Florida.                           tidal marshes, mangrove swamps, and intertidal flats, as well as the deepwater
                   10                                                                     habitats associated with bays, sounds, and coastal rivers. Palustrine wetlands

                 account for about 90% of all U.S. wetlands. They are inland, freshwater areas
                 of marshes, bogs, and swamps, and some brackish and salt marshes in and                                   FLOODPLAINS AS HABITAT
                 and semi-arid areas.                                                                               e Black ducks migrating in the Atlanticflyway use
                    . Wetland plants are particularly efficient converters of solar energy. Their                   the northern salt marshes as their primary wintering
                 major food value is achieved when they die and fragment to detritus. Numerous                      grounds.
                 fish and wildlife species feed in marshes and swamps or on organisms that                          0 Intertidal mudflats along the coasts are the prin-
                 were produced in such areas. Some animals spend their entire lives in flood-                       cipalfeeding grounds for migratory shorebirds, most
                 plain wetlands, while others use the wetlands primarily for reproduction,                          shorebirds breed in Alaskan and other tundra
                                                                                                                    ue ilands.
                                                                                                                    * Mississippi River floodplain s are the major resting
                                                                                                                    andjeeding groundsfor ducks and geese during their
                                             Typical Inland      Wetland                                            fall and spring migrations,
                                                                                                                    * During droughts in the prairie pothole region,
                                                                                                                    Alaska's wetlands are heavi4, usedfor nesting by
                                                                                                                    North American waterfowl.
                                                                                                                    0 Hawaii's wetlands are especially important to
                                                                                                                    endangered birds.
                         Upland                                                                                       Arizona's native cottonwood- willow associations
                                          Upland                                                                    support higher densities and a greater diversity of
                                                          A
                                                                                           Upland                   breeding birdspecies than an
                Gr  nd..ater                                                                                                                 _y other desert habitat.
                    n                           High Water
                  lsharge                  .-  - @=@ 1 1 @                                                            The prairie pothole region of the Dakotas is the
                                  tree rn'           Low, Watei
                                                7                   Wati
                                                                                                                       in breeding areafor wole7fowl in the LInited
                                                                                                                    States.
                                                           River

                 ------                                                                                               The San Pedro River's riparian ecosystem in
                 Seepage Wetland         Overflow Deepwater    Overflow           Depressional                      southeastern Arizona provides nesting, migratory, or
                     on Slope            Wetiand     Habitat   Wetland              Wetland                         wintering habitatfor at least 20 rapier species and
                                                                                                                    about 210 species of other birds. A stud
                                                                                                                                                      .y recorded 78
                                                                                                                    species of mammals in the grasslands corridor
                 nursery grounds, or for drinking water. About 50% of the endangered species                        between the riparian woodlands and adjacent moun-
                                                                                                                    tains, the second-hughest mammalian diversity in the
                 in the United States require wetland habitat at some point in their life cycles;                   world.
                 wetlands are crucial to the survival of the American crocodile, the manatee,
                 the whooping crane, and the Mississippi sandhill crane. Both coastal and
                 inland wetlands also provide valuable habitat for such furbearers as muskrat,
                 beaver, otter, mink, and raccoon, as well as numerous reptiles and amphibians.
                 Large mammals, such as black bears, white-tailed deer, and caribou, also find
                 refuge and food in wetland areas.

                 Riparian Systems
                      Riparian floodplains are distinct associations of soils, flora, and fauna
                 that occur in narrow strips along rivers, streams, or other bodies of water and
                 depend for survival upon high water tables and occasional flooding. They are

                                                                                                                    Canvasback duck, salt marsh, New England.

     r

                                                                                                                                                A

                                                                                                                    Great blue heron, Merrimack River, New Hampshire.
                                                                                     A:@

                 Healthy riparian ecosystems are essential for maintaining the biological diversiy of the nation's fiora. They
                 also provide aesthetic pleasure,
                 Wetlmd vegetation, Joyce Kilmer Memorial Forest, North Carolina.

                                                                                                generally more biologically diverse than the surrounding uplands and encom-
                                                                                                pass a broader range of moisture and soil conditions and a greater diversity
                                                                                                of flora and fauna than wetlands do. The Soil Conservation Service estimates
                                                                                                that there are 16 million acres of riparian land along streams, canals, lakes,
                                                                                                reservoirs, and tidal shorelines of rural, nonfederal portions of the United
                                                                                                States. Bottomland hardwood forests also are a major riparian ecosystem,
                                                                                                and they account for about 52 million acres, mostly in the South.
                                                                                                      Healthy riparian ecosystems provide community structure for raptors,
                                                                                                safe passage corridors to water for mammals, habitat for amphibians, and
                                                                                                cover and nutrients for fish. At elevations below 3,500 feet, they take the form
                                                                                                of lush strips of streamside vegetation that interrupt' the desert landscape.
                                                                                                These linear communities provide habitat for up to 801yo of the West's wildlife
                                                                                                species, and are essential for maintaining its healthy fish and wildlife popula-
                                                                                                tions. Cottonwood groves provide a high canopy and open understory essen-
                                                                          4
                                                                                                tial to certain birds of prey for hunting, while mesquite bosques provide lower,
                                                                                                denser ve tation ideal for colonial nesting by whitewing doves. Also depen-
                                                                                                             ge
                     Rivers andjloodplains provide   numerous recreational                      dent on riparian habitats are grey squirrels, river otters, muskrats, summer
                     opportunities-including hiking, camping, hunting, fish-                    tanagers, canyon frogs, tree frogs, and dove-tailed hawks.
                     ing, boating, swimming, bird-watching, picnicking jog-
                     ging, photography, ice skating and szmp@ observing
                     nature.

                     Above: Bicyclist, Boul&r Creek Pathway, Boul&r,
                     Colorado.

                     Below: Canoer, Nantahala River, North Carolina.

                                                                                                                                                                                                                     N,

                                                                                                                                                 "T

                                                                                                Arid region _floodplains, although apparently  desolate, actually provide habitat for most desert wildlife species.
                                                                                                Channel, floodplain, and rzparian habitat,    Verde River, Tonto National Forest, Arizona.

                                                                                                                                          Cultural Resources
                                                                                                       As used in this report, the cultural resources of floodplains include their
                                                                                                historic and archaeological sites, their scientific, recreational, and aesthetic
                                                              6@                                uses, as well as the harvest of the floodplains' natural and cultivated products.
                                                                                                Because water has always been basic to human survival, transportation, and
                                                                                                commerce, many sites of historic and archaeological significance lie in flood
                                                              t
                                                                                                plains. Floodplains provide opportunities for hiking, camping, hunting, fish
                                                                                                ing, boating, swimming, bird-watching, picnicking, jogging, photography, ice
                                                                                                skating, nature observing, as well as for scientific study and research, educa-
                                                                                                tional activities, and less tangible aesthetic benefits. Floodplains can provide
                                                                                                urban communities with a tremendous open-space and greenbelt resource.
                                                                                                       Inland floodplains are great sources of commercial timber. Much of the
                                                                                                82 million acres of commercial forested wetlands in the 49 continental states
                                                                                                lies within floodplains. The standing value of southern wetland forests alone
                                                                                                is $8 billion. The floodplains along larger rivers are prime agricultural lands
                                                                                                because of their flat terrain, abundant water supplies, and rich alluvial soils
                                                                                                periodically replenished by flooding. From 1956 to 1975 about 60% of the
                                                                                                U.S. commercial fish and shellfish harvest was made up of wetland-dependent
                                                                                                species. Several billion dollars are generated annually from this harvest and
                                                                                                from wetlands-dependent sport fishing.
                  12

                                                    Floods

                Floodplains are, by definition, lands that are formed by and continually sub-
                ject to inundation by water. Depending on the location, topography, soils, and
                weather conditions, that flooding can take a variety of forms. Riverine floods
                can result not only from heavy rainfall and rapid snowmelt but also from dam
                and levee failure, ice jams, and channel migration. Coastal flooding can be
                caused by hurricanes, winter storms, tsunamis, and rising sea level. Indi-
                vidual storms and long-term climate variations cause flooding around lakes.
                Other floodprone areas include alluvial fans, unstable and meandering chan-
                nels, and areas affected by land subsidence and ground failure. In addition,
                flooding due to surface runoff and locally inadequate drainage can be a major
                problem, particularly in rapidly urbanizing areas.

                                               Riverine Flooding
                     Riverine flooding-overflow of water from the channel onto the adjacent
                floodplain-is the most common type of flood. Hundreds occur each year in
                the United States.
                       Flashfloodng occurs in all 50 states: in narrow, steep valleys, on alluvial
                       fans, on denuded areas, and along urban drainage courses, usually as a
                       result of high intensity, short duration storms occurring on steep gradient
                       streams. Flash floods can be more dangerous than other floods because
                       of their suddenness, the velocity of the water, and the large amount of
                       debris carried by the flood waters.

                                                                                                                                           7

                                                                                                                                 Raw
                       Examples of'Recant Flash Floods Causing Serious Loss of Life
                   February 1972, Buffalo Creek, West Virginia-125 killed and hundreds of
                   homes washed away when a dam made of coal mine waste material gave way
                   after heavy rains.                                                                           Big Thompson Canyon, Colorado, follo-ing fl-h flood,
                                                                                                               July 1976.
                   June 1972, Rapid City, South'Dakota an(fadjacent areas-236 dead and
                   $100 million in property damage after a large, slow-moving thunderstorm
                   unleashed heavy rain on the slopes of the Black Hills.

                   July 1976, Big Thompson Canyon, Colorado-139 killed and millions of dol-
                   lars in property damage after a thunderstorm inundated the western third of the
                   canyon with 12 inches of rain in less than six hours.

                   July 1977, Johnstown, Pennsylvinia-77 dead and more th -an $200 million in
                   property damage when violent thunderstorms produced 11 inches of, rain over a
                   seven-county area in nine hours. Several dams failed, compounding thestream
                   flooding and causing 40 of the deaths.

                   September 1977, Kansas City, Missouri, and adjacent areas@25 killed and
                   $90 million in property damage when diundersto  'rms turned several.streams into
                   raging torrents, including "gentle" Brush Creek, which flows through the heart
                   of Kansas City.
                                                                                                                                                        VN

                   Source: Federal Emergency Management Agency

                     � Alluvialfanflooding can cause great damage because of the high veloci-                 Alluvial fan j7ooding at the mouth of ravines or the foot of
                                                                                                              mountains occurs throughout the United States, but is most
                       ties, large amounts of sediment and debris, and wide area covered by                   prevakni and poses the greatest hazard in the arid West.
                       the flood waters. Alluvial fans occur mostly along the base of moun-                   Mobile how park, Colorado river, near Parker, Arizona.
                       tains in the western states. An estimated 15-25% of the and West,
                       including Los Angeles and Las Vegas, is covered by alluvial fans.
                     � Unstable and meandering stream channels are also frequently flooded. Many of
                       them are the product of several decades of human activities, particularly
                       in the and and serni-arid West. Overgrazing, mining, forestry, urbani-
                       zation, gravel and sand extraction, and the construction of railroads,
                                                                                                                                                            13

                                                                                                               highways, dams, and irrigation facilities all have changed the vegetative
                                                                                                               cover, altered surface water patterns, changed the movement of sedi-
                                                                                                               ments, and lowered water tables. These changes have made water
                                                                                                               movement during floods difficult to predict.
                                                                                                               Icel'ains, which affect 35 states, cause a rapid rise of water both at the
                                                                                                               point of the jam and upstream; when the jam breaks, sudden down-
                                                                                                               stream flooding results. Because the waters are higher and their veloci-
                                                                                                               ties greater, damages usually exceed those that would have occurred
                                                                                                               without the jam. Additional damage can be caused by the force of the
                                                                                                               ice, as it builds in volume and expands overbank during the jam and
                      Storm drainage is a significant problem    in many large                                 then crashes downstream when the jam breaks.
                      urban areas, particularly if development   has been rapid
                      and not well planned, Drainage systems      must be designed                                                    Flooding from Surface Runoff
                      to handle infrequent, but potentially catastrophic, events.                           The runoff from heavy precipitation can overtax inadequate local drain-
                      Concrete-lined artificial channel carryingflood waters,
                      Baton Rouge, Louilmna.                                                        age systems and result in flooding outside of normal floodplains. These kinds
                                                                                                    of flooding problems generally intensify as areas become more urbanized.
                                                                                                    Frozen ground and heavy accumulations of snow can exacerbate the problem.

                                                                                                                                       Coastal Flooding and Erosion
                                                                                                            Coastal flooding and erosion result from storm surge (the rise in the
                                                                                                    water surface due to barometric pressure and the piling up of water as a
                                                                                                    result of wind) and wave action (the combination of wave set-up and wave
                                                                                                    runup). The frequency and magnitude of flooding and erosion vary consider-
                                                                                                    ably across the country@
                                                                                                            0  From 1899 to 1989 a total of 148 hurricanes and 135 tr*al slomu crossed
                                                                                                               or passed adjacent to the U.S. mainland.
                                                                                                            e  Northeasters-extratropical storms accompanied by strong winds-cause
                                                                                                               flooding along the north Atlantic coast.
                                                                                                            0  Tsunamis are sea waves generated by undersea earthquakes of over R6.5;
                                                                                                                                            -period, are of low height at sea, and can travel over
                                                                                                               they are very long
                                                                                                               500 mph. The entire Pacific coast of the United States, including
                                                                                                               Alaska and Hawaii, is subject to tsunamis.
                                                                                                            0  Shoreline erosion occurs either when storm surge and wave action move
                                                                                                               sediment offshore or when the alongshore flow of sediment is inter-
                                                                                                               rupted by natural forces or human activities. Natural erosion may be
                                                                                                               accelerated by partial or inadequate structural or nonstructural meas-
                                                                       W.
                                                                                                               ures intended to protect short reaches of eroding shoreline-such as
                      Hurricanes can   result in flooding of various kinds, from                               beach nourishment, artificial dunes, breakwaters, seawalls, bulkheads,
                      flashflooding and slow-rise riverine flooding due to heavy                               revetments, groins, andjetties.
                      precipitation, to coastalflooding due to storm surge.
                      Quinebaug River, Putnam, Connecticut, 1955, following                                                                                                                                         0
                      Hurricane Diane,
                                                                                                                  Number of Major Hurricanes Directly                                                 5        0      -2
                                                                                                                 Affecting the United States, 1899-1989
                                                                                                                                                                                                                       3
                                                                                                                                                                                                          0

                                                                                                                                                                                            4
                                                                                     4                                                                                              0
                      Hurricanes can cause severe clamage due to     the combined                                                                              6         5
                      effects of several agents-high winds, increased     wav  e ac-                                            15                   1
                      tion, heavy precipitation, storm surge, and other types of
                      flooding.
                      Damage near Charleston, South Carolina, following Hur-                                                                                                              22
                      ricane Hugo, September, 1989.                                                                                                                                          Q,

                    14                                                                              Source: National Hurricane Center, National Weather Service

                                                             Ground Failure
                          Areas subject to ground failure often suffer from nwdAws and mudfloods,
                   two forms of landslides. Urban development alters hillslope configurations
                   and upsets established equilibrium, triggering the natural instability of many
                   slopes and sometimes reactivating old landslides. Mud and debris may fill
                   drainage charm        els and sediment basins, causing flood waters to suddenly
                   inundate areas outside the floodplain. Mud flows and mud floods may cause
                   more severe damage than other flooding because of the force of the debris-
                   filled water and the combination of debris and sediment.
                          Both,natural and human-induced subs&ence can increase flood damage in
                   areas of high groundwater, tides, storm surges, or overbank stream flow. It
                   can also block or otherwise alter drainage patterns, leading to deeper or unex-
                   pected flooding. Subsidence occurs in at least 38 states.
                          Lique t' is a type of ground failure triggered by seismic waves passing
                                .fac wn
                   through unconsolidated and saturated soil. Depending on the character of the
                                                                                                                                                   jAr                                              'r
                   soil, the amount of water, and the drainage potential, the soils may sink or
                   become liquid. This can result in serious flooding of structures built on fill or
                   saturated soils-as in parts of San Francisco and Anchorage.

                                                                                                                                                                         01

                                                                       X
                                                                                                                                              Natural coastal erosion can be great@v accelerated by wave
                                                                                                                                              action during storms and hurricanes. Combined with inap-
                                                                                                                                              propriate construction in coastal areas, this natural process
                                                                                                                                              can result in disaster,
                                                                                                                                              Big Rock Beach, Malibu, California, following PaciJic
                                                                                                                                              winter storm, 1983.

                                                                                                           C
                                                                                            *W,

                   Mudflows and mudfloodf are two types of landslides that can    be aggravated by human  development. Addi-
                   tionally, they can resultfrom other natural hazards, such as earthquakes and volcanic eruptions.
                   Toutle River, Wohin,,ton State, followin,, the eruption of Mt. St. Helens, May 1980.
                                                                                                                                                                                                    14

                                                                                                                                                                                                    15

                                                                                                                         Fluctuating Lake Levels
                                                                                              Closed-basin lakes are susceptible to dramatic (5- to 15- foot), long-term
                                                                                       fluctuations in their water levels as a result of variations in precipitation, run-
                                                                                       off, and evapotranspiration. Flooding associated with this situation can last
                                                                                       for years; examples of such lakes are the Salton Sea, the Great Salt Lake, and
                                                                                       the Great Lakes. Short-term fluctuations can be triggered by sustained strong
                                                                                       winds and by sharp changes in barometric pressure. Human activities, such
                                                                                       as dredging, diversions, water consumption, and regulation by structural
                                                                                       works, can also affect lake levels.

                                                                                                     Changes In Water Levels in the Great Lakes, 1900-1986
                                                                                                                         (Lake Sur-face Elevation, in Feet)
                                                                                          Lake                           Monthly Mean                         I         Range
                                                                                                                              1900-1986                    (Winter low to summer high
                                                                                                                                                                  monthly means)

                                                                                                                 Average    Maximum Minimum Average Maximum Minimum
                                                                                          Superior               600.61       602.24        598.23          1.2         2.1            0.4
                                                                                          Michigari-Huron        578.33       581.62        575.35          1.2         2.1            0.4
                                                                                          St. Clair              573.40       576.69        569.86          1.7         3.3            0.4
                                                                                          Erie                   570.50       573.70        567.49          1.6         2.8            0.9
                                                                                          Ontario                244.73       248.06        241.45          2.0         3.6            0.7

                                                                                          Levels are referenced to International Great Lakes Datum 1955.

                                                                                          Source: U.S. Army Corps of Engineers

                                                                                                                         Floodplain Losses

                                                              Am@-                     Throughout the history of the United States, the prevailing view has been
                                                                                       that humans should use and modify the natural environment, including flood-
                                                                                       plains, to meet their needs. For centuries people have been settling on the banks
                                                                                       of the country's rivers, streams, and oceans, taking advantage of the water
                                                                                       supply, transportation, energy source, wildlife habitat, and other benefits flood-
                                                                                       plains provide. Unfortunately, human development on floodplains usually
                                                                                       results in flood damages. In the United States the result of this widespread
                                                                                       damage was a second wave of activity, during which individuals and govern-
                                                                                       ments enthusiastically engaged in the construction of dams and reservoirs,
                                                                                       levees, floodwalls, and stream channelization projects in efforts to prevent
                      toricaly, the development of the United States has               or limit damages to development that was either knowingly or inadvertently
                   procee&d along the principal waterways of the nation,               placed within the floodplain. Thousands of water supply projects, particularly
                   where cities have been developed and redeveloped over the           in the and West, dramatically changed the natural resources of riparian areas.
                   &cades.                                                             Millions of acres of inland and tidal wetlands were filled or drained, causing
                   Pittsburgh, Pennsylvaiu@, early 1960s.                              loss of natural flood storage areas, a lowered capacity for filtration of pollu-
                   (Compare this photograph with those on page 24.)                    tants and groundwater recharge, and reduction or elimination of some
                                                                                       wildlife species.
                                                                                             By the late 1970s it was estimated that from 3.5 to 5.5 million acres of
                                                                                       floodplain land had been developed for urban use, including more than 6,000
                                                                                       communities with populations of 2,500 or more. Annual growth in these
                                                                                       floodplain areas was between 1.5% and 2.5% during the 1970s, roughly twice
                                                                                       that of the country as a whole. The coastlines of the United States have been
                                                                                       attracting people and their accompanying property and infrastructure in ever-
                                                                                       increasing numbers for several decades. The 1980 U.S. Census units within
                                                                                       50 miles of the Atlantic and Gulf coastlines increased in population from 34.1
                                                                                       million in 1940 to 63.3 million in 1980-an increase of 857o, compared with
                                                                                       707o for the nation as a whole. The population of Gulf Coast counties
                                                                                       increased by 2007c.
                                                                                             In 1991 the floodplain lands in 17,466 examined communities occupied a
                                                                                       total of 146,600 square miles (93.8 million acres), including about 9.6 million
                 16

                   households and $390 billion in property. Florida was the state with the highest
                   composite risk, followed by California, Texas, Louisiana, and New Jersey.
                          This large-scale development and modification of riverine and coastal
                   floodplains has resulted in a major increase in the land area of the United
                   States that may be economically developed and used, but at a high price
                   extracted annually in deaths, personal injury and suffering, economic loss,
                   and damage to or destruction of natural and cultural resources. There are two
                   main kinds of floodplain losses: loss of life and property, and loss of natural
                   and cultural resources. Both types continue to occur even with increased aware-
                   ness of the value of floodplains and of the risks of floodplain occupancy. The
                   actual and relative amounts of these losses are not well quantified.

                                                             44

                   It has been estimated that 3.5 to 5 5. million acres offloodplain land had been developedfor urban use  by
                   the late 1970s. In many cases,  this change has resulted in greatly altered river corridors and adjacent lands.
                   Channel modification, Sioux Ciy, Iowa.

                                  Average Annual Flood Damages for Five-Year Periods
                                                              in the U.S., 1916-85
                   5500

                   5000-                                                                                                                         Although there is no unifornz measure offlood losses,
                                           Damages                                                                                               flooding clearly constitutes the most pervasive and costly
                   4500-                                                                                                                         hazardfacing the nation. From 1965 to 1989, total as-
                                                                                                                                                 sistance payments for Presidentially declared disasters
                   4000-                   Damages (1985 $)                                                                                      amounted to almost $6 8 billion. Of that, $5.2 billion
              La                                                                                                                                 was allocated for flood- and hurricane-related damage.
              .9   3500-                   DamageS/200 million population                                                                        Flooding, Prairie du Chien, Wisconsin, 1975.
              6
              a                            (1985$)
              %_   3000-
              0
              U)
                   2500-

                   2000-
              0

                   1500-

                   1000-

                      500

                         0
                            1920 25 30 35 40 45 50 55 60 65 70 75 80 85

                                                   Last Year of Five-Year Period

                   Source: National Weather Senice

                                                                                                                                    Loss of Life and Property
                                                                                                       Between 1916 and 1985 there were, on average, 101 flood-related deaths
                                                                                               annually; there is no indication that deaths are increasing or decreasing on a
                                                                                               per capita basis. On the other hand, there definitely was an increase in flood
                                                                                               damages over that 70-year period. Per capita flood damages were almost 2.5
                                                                                               times as great from 1951 to 1985 as from 1916 through 1950, after adjusting
                                                                                               for inflation. Property losses from floods appear to have been fairly constant
                                                                                               in relation to the overall national economy. For example, flood losses in 1937
                                                                                               in the Ohio and lower Mississippi River basins ($440 million) amounted to
                                                                                               .00497o of the GNP for that year. Flood damages in 1983 ($4 billion)
                     Although less dramatic than urban or coastalflooding,                     amounted to only .00127o of GNP. Consistent, reliable data on historic flood
                     ruralflooding and consequent agricultural losses account                  deaths and damages are still not being collected. Information on the financial
                     for almost 50To offlood damages in the United States.                     aid given by many federal and state agencies is not available in a form that
                     Flooding along the Snohomish River, Washington State,                     separates flood-related damages from other types of natural and technological
                     November 1986.                                                            disasters. Nevertheless, there are numerous figures available to help establish
                                                                                               the type and extent of damages suffered.
                                                                                                       0  Floods account for more losses than any other natural disaster in the
                                                                                                          United States (with the exception of drought losses during certain years
                                                                                                          or long-term periods). In most years flood damages constitute the bulk
                                                                                                          of federal financial aid for disasters.
                                                                                                       0  From 1981 to 1985, about 23% of all Presidentially declared disasters
                           -7                                                                             involved coastal flooding, and about 49% of federal disaster aid obliga
                     W71                                                                                  tions were attributable to coastal damage.
                                                                                                       9  A total of $2.6 billion in flood insurance claims were paid out by the
                                                                                                          National Flood Insurance Program from 1978 to 1987. Over 31% were
                                                                                                                                                                -year floodplain-the result of
                                                                                                          for flooding in areas outside the 100
                                                                                                          rapid urbanization that exceeds the capacity of managers to remap and
                     Damages to inftastructure may account for as much as                                 regulate, or to manage stormwater.
                     25 % of the total damages incurred during flooding                                0  The Federal Highway Administration provided $442.3 million in emer-
                     Bridge damaged by _flooding, Jefftrson Island, Louisiana,                            gency relief from 1986 through 1989.
                     1979.
                                                                                                       0  About half of the nation's annual flood damages are agricultural losses.
                                                                                                       0 The Small Business Administration issued $78.7 million in economic
                                                                                                          injury disaster loans and $67.9 million in physical disaster loans in
                                                                                                          fiscal year 1989.
                                                                                                       0  On irrigated cropland, flooding can damage irrigation facilities, such
                                                                                                          as ditches, pipelines, and sprinklers. Sediment deposited by flood
                                                                           T,                             waters can reduce long-term yield by covering fertile land with infertile
                                                                                                          deposits and can damage existing crops by interfering with their
                                                                                                          growth. These losses range from $150 to $500 million annually.
                                                                                                       0  A review of eight disasters from the 1950s and 1960s found that
                                                                                                          damages to infrastructure accounted for about 25% of the total
                                                                                                          damages. Other estimates put that figure at 10-19%.
                     In a 1971 study, the Corps found that approximaie@y                               0  Over three-fourths of all Presidentially declared disasters involve flash
                     24 To of the nation's shoreline was significantly eroding.                           flooding; flash floods have been the cause of most weather-related deaths
                     Two-thirds of this land was privately owned.                                         in the United States.
                     Dune erosion and house collapse, Sandwich, Mas-
                     sachusetts.                                                                       0  A study of streambank erosion estimated $295 million in average
                                                                                                          annual damages. Neither the damages from nor costs of coastal erosion
                                                                                                          have been estimated.

                                                                                                       0  Total national losses from lake level fluctuations exceeded $250 million
                                                                                                          from 1981-1986.
                                                                                                       0  The overall damages and cleanup costs from the 1980 eruption of Mt.
                                                                                                          St. Helens, which caused catastrophic flooding and mudflows, were
                                                                                                          estimated at $1.2 billion; over $875 million was needed to restore land,
                                                                                                          clean up rivers, and provide flood protection to area communities.
                                                                                                       0  Three tsunamis have resulted in losses in recent times: 173 deaths in
                                                                                                          Hawaii in 1946; 61 deaths in Hawaii in 1960; and 107 deaths in Alaska,
                                                                                                          4 in Oregon, and 11 in California in 1964, plus $100 million damage
                                                                                                          on the West Coast.

                 18

                                                             Streambank Erosion
                                           Average Annual Damages in $ Thousands

                            P 'fic-North     t              So ns-_Re_d-AP-nr-_                         New Engl n
                                                                 1,200

                                                                           per    sissi i
                                                  r                          5,ii @ 0      ':@"jat L
                                                                                                   7
                                  real Be @n,@                       Misso ri Basin
                                     500 S@                             16,                                                              The Corps estimates that in the United States there are
                              alifor 'a                                                    hioVallO                                      574,500 miles ofstrearn bank with erosion problems-
                                                                                           5
                              56,200     i@-@40 Basin                                                           iddle Atlantic           142, 100 with serious problems. About 78 % of all stream
                                                4,P                                          e      Y             10,900                 bank erosion takes place west of the main stem of the
                                                  I                                                                                      Mississippi River.
                                                                   LArkan     as-W te- ed
                                                                               350
                                                         Rio Grande      Low r A     Will
                                                                               38,
                                                                     Texas ulf                  Sout At ntic Gulf
                                          2SI                              00
                                      it 1 000
                                                                                       W
                                                                           L=0              __J

                                                             U.S. Total   $294,600,000

                          Source: U.S. Army Corps of Engineers

                                         Loss of Natural and Cultural Rcsources
                         All three types of floodplain resources-water, living, and cultural-are
                   threatened by human use of the floodplain, whether for urban development or
                   seemingly benign agriculture or forestry. Furthermore, because floodplains are
                   integrated natural systerns, tampering with any one of the component natural
                   processes may often lead to trouble. Increased runoff resulting from wide-
                   spread clearing of vegetation, destruction of wetlands, dune removal, paving,
                   roofing, and other activities can increase flood peaks, stream erosion, and
                   sediment transfer. Blocking runoff or interrupting the movernent of ground-
                   water can raise flood profiles, increase pollution, and interfere with ground-
                   water balances and the distribution of sediment. Fertilizers, septic systems,
                   chemical and petroleum spills, and leached materials from waste disposal
                   areas can degrade the surface and groundwater resources of floodplains.
                   Recreational and commercial river traffic often seriously contributes to stream-
                   bank erosion. Increased sediment can bury food sources and spawning areas
                                                                                                                                                                        7W
                   and pollution can poison plants, animals, and other living things. Develop-                                           Human occupation   and use of a Jlooaplain threatens its
                                                                                                                                         natural resources in many ways. Sign@ficant arwng these
                   ment can remove shelter and food, and prevent fish and other wildlife from                                            is the potentialfor increased pollution due to improper
                   moving through their habitat. Erosion of coastal wetlands and filling of wet-                                         waste disposal, spills, and various forms of nonpoint
                   lands destroys habitat. In many cases, developed floodplains do not have the                                          source pollution.
                   aesthetic and recreational attributes of natural ones. Improper agricultural
                   and forestry practices can be just as destructive of natural floodplain values
                   as poorly planned urban development.
                         The nature of the value of natural floodplains makes the damage to them
                   difficult to quantify, but the losses have been assessed even if no economic
                   value has been assigned.
                            Over 90% of the United States' coastal barriers are subject to flooding
                            and erosion because of their seaward exposure, inherent instability, and
                            relatively low-lying topography. In spite of these risks, 14% of the area
                            of coastal barriers is urbanized (compared to only 3 % of the entire
                            mainland), including Atlantic City, Ocean City, Virginia Beach, and
                            Miami. This development also interferes with the natural ability of the
                            barriers to absorb storm energies, thereby reducing protection for
                            mainland populations and development as well.
                                                                                                                                                                                                 19

                                                                                                          F''

                                                                 must be   carefulo
                    just as urban development offloodplains
                    planned, the effects of agricultural andforestry uses must
                    also be analyzed and un&rstood before changes in a j7ood-                           0
                    plain are made.
                    Connecticut River near Deerf@rld, Massachusetts.                                                                                                                          Jor-

                                                                                                  J

                                                                                                  Development   in a j7oodplain may 1) increase runoff, 2) block runoff and interrupt groundwater        movement,
                                                                                                  and 3) increase pollution, It can affect living resources and habitat in numerous, sometimes unpredictable,
                                                                                                  ways.
                                                                                                  Development in coastal marshland of Louisiana.

                                                                                                         0  Human activities have already profoundly affected floodplains and the
                                                                                                            nature of flooding throughout the and and semi-arid Southwest, where
                                                                                                            rapid development is expected to continue. Many changes that began
                                                                                                            450 years ago with the introduction of cattle are still affecting the basic
                                                                                                            hydrologic cycle and geomorphology of the region. Plant and animal
                                                                                                            associations that evolved for 10,000 years have been irreversibly altered,
                                                                                                            and the effects of this are still only vaguely understood and generally
                                                                                                            unmanaged.
                                                                                                            About 54% of the original 215 million acres of wetlands in the nation
                    Over the years,  the conversion of wetlands to other   uses has
                    resulted in more than heq of all US. wetlands being lost.                               have been lost since European settlement. A recent U.S. Fish and
                    Dredging near Amelia, Louisiana.                                                        Wildlife Service study estimates that there are about 100 million acres,
                                                                                                            or about 55o of the land mass, left in the continental United States,
                                                                                                            and the U.S. Office of Technology Assessment estimates that there are
                                                                                                            about 200 million acres, or about 60%, in Alaska. Historically, the
                                                                                                            greatest portion of this loss by far was the result of draining wetlands
                                                                                                                                 Original and Remaining Acreages
                                                                                                                                of Wetlands in the Lower 48 States

                                                                                                                    Lost (54%)

                                                                                                                                                               Remaining (46%)

                                                                                                  Source. Fish and Wildlife Service, U.S. Department of the Interior
                  20

                                for conversion to agriculture. Major areas of bottomland hardwood
                                forests have been cleared, drained, or converted to agriculture. Agricul-
                                tural uses were estimated to account for 54ro/o of the 300,000 acres lost
                                annually from the mid-1970s to the mid-1980s.
                                Riparian ecosystems are being degraded and destroyed throughout the
                                United States. The lower 48 states originally contained 75-100 million
                                acres of indigenous, woody riparian habitat, but today only 35 million
                                remain in nearly natural condition. The rest have been inundated by
                                reservoirs, channelized, dammed, riprapped, converted to agricultural
                                use, overgrazed, paved, or altered by a combination of factors that have
                                impeded their ability to stabilize and maintain the biological diversity
                                of their own watersheds. Riparian habitats have been lost in every
                                region of the country.
                                Channelization and other flood control projects can destroy riparian
                                habitat by clearing vegetation; eliminating sandbars, islands, and pro-
                                ductive backwater areas; and accelerating bank erosion. Between 1940
                                and 1971 the U.S. Army Corps of Engineers assisted in navigation and
                                flood control projects to alter 11,000 miles of streams. The Soil Conser-
                                vation Service has installed 10,700 miles of channel modifications.
                                Dams can alter riparian habitat in many ways, such as drowning it
                                under reservoirs, desiccating it by downstream dewatering, or render
                                ing it non -regenerative by interrupting the natural flood cycle. The
                                nation's 68,153 nonfederal dams have altered or destroyed tens or hun-
                                dreds of thousands of miles of riparian habitat. Impoundments by the                                                      Alteration is widely used to controlflooding by increasing
                                federal government have transformed major river systems, including                                                        the carrying capaci!y of a stream channel. Techniques in-
                                                                                                                                                          clude straightening, deepening, widening, or paving the
                                the Columbia, Colorado, Missouri, and Tennessee, into a series of                                                         channel; removing debris; raising or enlarging bridges and
                                artificial lakes, severely decreasing the diversity of habitats available                                                 culverts; removing dams and other obstructions; and in-
                                to wildlife but creating other habitats and environments.                                                                 stalling underground conduits. However, unless carefully
                                                                                                                                                          planned and executed, such channel modificatton can sig-
                                By overgrazing, trampling vegetation, compacting the soil, and break-                                                     nzficant@v affect riparian habitat,
                                ing down streambanks, livestock have seriously damaged watersheds                                                         Artificial channel (buried conduit) under construction,
                                and riparian zones. These impacts have led to increased soil erosion,                                                     LaPlace, Louisiana.
                                higher nutrient load in streams, bank erosion, and lowering of water
                                tables. Inadequate livestock management has been responsible for the
                                serious lack of riparian habitat regeneration on federal rangelands in
                                the West.
                                Lowering of the water table in and and semi-arid regions causes a
                                drastic and often permanent degradation of the floodplain. In many
                                areas, a high water table and accompanying pools and springs are the
                                only sources of moisture for riparian vegetation and native animals.
                                Introduction of non-native plants has also significantly contributed
                                to alteration of floodplain habitat. Salt cedar, for example, which was
                                imported to North America during the 19th century, has become the
                                predominant riparian tree species on the lower Colorado, the lower Rio
                                Grande, and Pecos rivers. It covers some 500 square miles in those basins
                                alone, and makes the riparian areas less suitable to many native birds.
                                                                                                                                                          The introduction of cattle to the American West has had a
                                                                                                                                                          fundamental effect on the nation's landscape-in particu-
                                                                                                                                                          lar, on riparian lands in semi-arid environments. In many
                                                                                                                                                          cases the result has been soil compaction, loss of vegeta-
                                                                                                                                                          tion, increased erosion, and the consequent deterioration of
                                                                                                                                                          floodplains, river banks, and river water quality.

                                                                                                                                                                                                                     21

                          PART II
                   MANA'C,INGFLooDPLAIN'S
                     TO.RtDUCE LossES -

                                                                                                       The History of Floodplain Management

                                                                                               Before 1965, government action to reduce floodplain losses was primarily a
                                                                                               response to significant loss of life or property damage. Most of these efforts
                                                                                               sought to control flooding through structural measures. During the mid-1960s,
                                                                                               federal policy began to broaden to include nonstructural means. The last 25
                                                                                               years have witnessed a major expansion in floodplain management, incorpo-
                                                                                               rating better ways for analyzing and predicting flooding, paying appropriate
                                                                                               attention to the natural resources of floodplains, and adjusting the roles of
                                                                                               federal, state, and local governments and the private sector.

                                                                                                                       1900-1960: The Structural, Federal Era
                                                                                                       During the 1800s and early 1900s, flood control efforts were undertaken
                                                                                               by levee districts, conservancy districts, other local and quasi-public groups,
                                                                                               and individual landowners. Federal involvement was sporadic and concerned
                                                                                               mainly with flood impacts on navigation, forestry, or agriculture. After the Civil
                                                                                               War, Congress authorized federal agencies to begin stream gaging as a start
                                                                                               toward flood forecasting and warning, but federal involvement still was limited.
                                                                                                       After two decades of major flooding along the Mississippi, Ohio,
                                                                                               Potomac, Susquehanna, and various New England rivers, Congress com-
                                                                                               mitted the federal government to flood control of all navigable rivers in the
                                                                                               nation in the Flood Control Acts of 1917, 1928, 1936, and 1938. The com-
                                                                                               bined effect of these acts was the federal government's assumption of the full
                                                                                               cost of building and maintaining reservoirs and channel modifications, and
                                                                                               the placement of most of the responsibility for efforts to control floods in the
                                                                                               hands of the Corps. These laws did mention other measures for reducing
                                                                                               flood damages, such as evacuation, watershed improvement, and reconcilia-
                                                                                               tion of needs of upstream and downstream users, but the emphasis was on
                                                                                               controlling flooding with such structures as dams, levees, and channel
                                                                                               modifications.
                                                                                                       Twenty-five years later the Corps' authorized flood control program
                                                                                               encompassed 220 reservoirs (90 million acre feet of flood control capacity),
                                                                                               over 9,000 miles of levees and floodwalls, and 7,400 miles of channel modifi
                                                                                               cations-a total of 900 projects with an estimated federal cost of $9 billion.
                                                                                               Other federal agencies also became involved in flood control. The Tennessee
                     In the kiter part of this century, the scope of floodplain                Valley Authority's regional program of resource development included con-
                     numagement broadened to encompass a wide range of tech-                   struction of dams and reservoirs for flood control and other purposes. The
                     niques. The "Point Area" of Pittsburgh, fenmylvania, at                   Bureau of Reclamation and the U.S. Department of Agriculture began
                     the confluence of the A14heny and Monongahela Rivers,                     including flood control with other project considerations. During the 1930-
                     demonstrates these advances. For example, the transporta-                 1950 period the U.S. Forest Service established research watersheds to study
                     tion corridor in thefireground has been replaced by an                               i Id and timing of flows from forest and range watersheds. The
                     open spa-ce park, highways have been eleevaled, and promi-                water yie                1
                     nent structures have been floodproofed. These physical                    Coweeta Hydrologic Laboratory in North Carolina was established in 1934
                     changes, along with a comprehensive system of upstream                    as the first of these watersheds. The Soil Conservation Service began helping
                     flood control, land use controls, and a coordinated flood                 individual landowners in 2,600 soil conservation districts to use conservation
                     warning and preparedness program, have signifi@anty                       measures, including flood prevention.
                     reduced theJZood hazard in downtown Pittsburgh.                                   Along with federal involvement *in flood control came federal relief for
                     Above: Pittsburgh, Pennsylvania, Point Area 1948.                                             1
                     Below: Pittsburgh, Pennsylvania, Point Area 1982.                         flood victims. The Federal Disaster Act of 1950 was the nation's first compre-
                                                                                               hensive disaster relief act, and Small Business Administration disaster relief
                                                                                               programs were also begun in the 1950s.
                                                                                                       Before the 1960s a number of single-purpose federal laws and programs
                                                                                               protected various specific natural resources and thus indirectly helped protect
                                                                                               the natural resources of some floodplains. For example, the creation of
                                                                                               national parks and federal forest reserves resulted in the protection of signifi
                                                                                               cant areas of natural floodplains. Other laws protected wildlife habitat and
                                                                              "I               preserved open space for conservation and recreation, thus ensuring that
                                                                                               some floodplain areas would be left in their natural states.

                                                                                                                                    1960s: A Time of Change
                                                                                                       Despite the billions of dollars in federal investments in structural
                                                                                               projects, and the demonstrated effectiveness of these measures, flood losses
                Previous page: Davis Dam, Colorado River, near Bull-                           and disaster relief costs continued to rise because of unwise occupancy and
                head City, Arzow.                                                              use of the nation's floodplains. Thus, broader approaches were studied and

                  24

                 applied, including zoning and other land use regulation, flood forecasting,
                 federal flood insurance, relocation of property, and alternative water storage
                 techniques. Major steps were taken to redefine federal policy Section 206
                 of the Flood Control Act of 1960 authorized the Corps to provide technical
                 services and planning assistance to communities for wise use of the floodplain
                 and for ameliorating the flood hazard. The Corps began producing maps and
                 floodplain information reports describing a community's flood hazard from
                 a broader perspective. The President's water policy statement of 1962 estab-
                 lished policies and procedures for comprehensive river basin plans. The Water
                 Resources Planning Act of 1965 created the U.S. Water Resources Council
                 and authorized federal-state river basin commissions for comprehensive
                 basin planning.
                       House Document 465, the report of a Bureau of the Budget Task Force
                 on Federal Flood Control Policy, advocated a broader perspective on flood
                 control within the context of floodplain development and use. Executive Order
                 11296, Flood Hazard Evaluation, directed all federal agencies to evaluate the
                 flood hazard before undertaking federally financed or supported actions and
                 to play a lead role in preventing uneconomic use and development of flood-
                 plains. Fifteen states, most notably Wisconsin and Minnesota, adopted flood-
                 plain management programs, some of them providing for strict regulation.
                 Local governments also began trying to deal with the hazard in a more com-
                 prehensive way, usually with assistance from a state or federal agency such as
                 the Tennessee Valley Authority.

                                                                         HISTORY OF
                                      A UNIFIED NATIONAL PROGRAM FOR FLOODPLAIN MANAGEMENT
                   House Document 465, A UnfiLed Nm@nal Progranifor Managing Flood Losses, was submitted to Congress by President Lyndon
                   Johnson in August 1966. It had been prepared by the Task Force on Flood Control Policy at the administration's request
                   in an attempt to slow the mounting national toll of flood losses, unchecked by over $7 billion in national investments
                   in flood control projects since 1936. House Document 465 recognized the need for a unified approach and for new
                   planning measures, and made 16 recommendations for federal agencya'ction to begin implementation of a program-
                   including new legislation, specific studies, and new programs for collecting and disseminating flood-related information.
                   A Unified National Program, 1976
                   In response to a 1968 Bureau of theBudget request for a repon pursuant to a directive in Section 1302(c), of the National
                   Flood Insurance Act, and to a 1975 U.S. General Accounting Office report criticizing House Document 465 and Execu-
                   tive Order 11296, the U.S. Water Resources Council submitted to the President the UnifLed National Programfor Flood-
                   pt2in Monagernent in 1976. This revision, whose tide change reflected A significant recognition that more than flood losses
                   were involved, established a more detailed framework for the program, described the greatly changed context in which
                   it would be implemented (numerous changes in flood-related federal programs had taken place), and added manage-
                   ment strategies and tools for federal, state, and local decisionmakers to use. The report focused on the need for improved
                   coordination, which was cited as the "weakest component of current management efforts."
                   1979 Revisions to a Unified National Program
                   Although the 1976 Unified National Program made a significant step forward in floodplain management, its very
                   effectiveness made it quickly dated. Several executive level actions-President Carter's floodplain management policy
                   articulated in 1977, Executive Orders 11988 and 11990, and the President's 1978 water policy initiatives-were soon
                   taken, making the 1976 version obsolete. The Federal Interagency Floodplain Management Task Force updated and
                   refined the Unified National Program in a report submitted by the Water Resources Council to the President in 1979.
                   This revision incorporated federal concern with the "natural and beneficial values" of floodplains, responded to the
                   President's policy directives, expanded the strategies (adding two: restoration of natural values and preservation of
                   natural values), tools, and conceptual framework accordingly, and emphasized the insufficient awareness of alterna-
                   tive strategies due to "lack of adequate technical and procedural information to guide floodplain decision-makers."
                   1986 Revisions to a Unified National Program
                   In 1982, the Office of Management and the Budget assigned responsibility for the Unified National Program to the
                   Federal Emergency Management Agency, which assumed chair of the Interagency Task Force. The Task Force sub-
                   mitted an updated Unified National Program in 1986, noting that the 1979 report had become "dated by the relative
                   success and changes in federal programs and by the strengthening of floodplain management capability at the state
                   and local levels." These changes included the use of federal interagency hazard mitigation teams, passage of the 1982
                   Coastal Barrier Resources Act restricting federal expenditures that might encourage development of coastal barriers
                   along the Atlantic and Gulf coasts, and completion of two major National Science Foundation studies on flood haz-
                   ard mitigation. The report included more explicit recommendations for the federal role in supporting state and local
                   initiatives.

                                                                                                                                                                            75

                                                                                                      Two major pieces of legislation rounded out the change in federal policy.
                                                                                               In 1969 the National Environmental Policy Act provided for consideration of
                                                                                               environmental values in all federal and federally supported actions, making
                                                                                               it possible to recognize the multiple values of floodplains. The National Flood
                                                                                               Insurance Act of 1968 made federally subsidized flood insurance available to
                                                                                               participating communities, contingent upon their implementing nonstructural
                                                                                               flood loss reduction measures embodied in local floodplain management
                                                                                               regulations.

                                                                                                                            1970s: The Environmental Decade
                                                                                                      During the 1970s numerous state and federal environmental laws and
                                                                                               programs and water resources initiatives began to decentralize water manage-
                                                                                               ment and bring about a much broader perspective on floodplains. Numerous
                                                                                               federal programs took shape for water quality management, pollution and
                                                                                               erosion control, watershed management, and protection of groundwater,
                                                                                               aquifers, inland and coastal wetlands, barrier islands, and specific habitats.
                                                                                               Complementary legislation was passed by many states, requiring environ-
                                                                                               mental quality review and impact assessments at state and local levels.
                                                                                                      During this decade, changes were made in the National Flood Insurance
                                                                                               Program; a proposal for a Unified National Program for Floodplain Manage-
                                                                                               ment was issued and later updated; and executive orders on floodplain man-
                                                                                               agement and protection of wetlands were issued, making disaster relief contin-
                                                                                               gent upon mitigation action and requiring the consideration of nonstructural
                                                                                               measures in federal flood control projects.
                                                                                                      State and local involvement in floodplain management increased with the
                                                                                               appointment of National Flood Insurance Program coordinators in all states,
                                                                                               the adoption by more states of regulatory programs, increases in state budgets
                                                                                               for floodplain management, and the adoption of resource conservation legisla-
                                                                                               tion. About 17,000 communities adopted floodplain management regulations,
                                                                                               and many adopted regulations to manage other local resources, such as wet-
                                                                      -9,                      lands and coastal areas.

                                                                               d
                                                                                                                                 1980s: Continuing Evolution
                                                                                                      More attention was given to implementing policies and programs for
                                                                                               managing floodplains during the 1980s. The federal government took the role
                                                                                               of coordinator and provider of technical assistance, while state and local gov-
                                                                                               ernments gradually fashioned floodplain management strategies appropriate
                                                                                               to their own jurisdictions. Interagency agreements were crafted to establish
                                                                                               common policy on nonstructural measures and to evaluate floodplain manage-
                                                                                               ment options after disasters. The Coastal Barrier Resources Act of 1982 estab-
                   Coastal management in the     Unzied States is shaped by the                lished a policy of nondevelopment and avoidance of high hazard areas by pro-
                   federal Coastal Zone Management Act of 1972 and the                         hibiting new federal expenditures on certain undeveloped coastal barriers.
                   Coastal Barrier Resources Act of 1982. The former author-                          The natural and cultural resources of floodplains received more protec-
                   ized federal grants to states for development and implemen-
                   tation of coastal management programs for water and land                    tion   through multipurpose, often federally supported projects for open space,
                   resources in coastal zones. As amended, the Act incor-                      recreation, urban renewal, greenbelt, and waterfront redevelopment.
                   porates both Aod loss reduction and protection of natural                          State and local officials became even more involved in hazard mitiga-
                   resources into program goals. The latter legislation estab-                 tion planning with the implementation of requirements for planning after all
                   lished a system of largeo undeveloped coastal barriers                      Presidentially declared disasters and with participation in interagency hazard
                   along the Atlantic and Gu@f coasts in which federalo sub-
                   sidized development is restricted.                                          mitigation teams.
                   Sand dunes, Santa Rosa Island, Fkrzda.
                                                                                                                    The Management Framework

                                                                                               Like any activity, floodplain management is carried out within a structure
                                                                                               of legislative, administrative, economic, and judicial opportunities and con-
                                                                                               straints. The way in which floodplain lands and waters are handled, decisions
                                                                                               are made and actions taken-whether by the U.S. Congress or by a single
                                                                                               homeowner in a floodprone area-depends upon the relevant law, the policies
                   rz

                                                                                               and programs of government agencies, funding, public interest and opinion,
                                                                                               and the availability of needed information. The framework for floodplain
                                                                                               management has been strengthened significantly since the 1960s. Before then,
                                                                                               flood loss reduction was largely dependent upon flood control works and fed-
                                                                                               eral actions; at the same time, a number of single-purpose federal laws and
                                                                                               programs protected various natural resources, only indirectly addressing pro-
                26

                                Strategies and Tools for Floodplain Management

                  Strategy A. Modify Susceptibility to Flood Damage and Disruption
                  1. FloodpIain Regulations
                       a) @ State regulations for flood hazard areas
                       b) Local regulations for flood hazard areas
                          1)  Zoning
                          2)  Subdivision regulations
                          3)  Building codes
                          4)  Housing codes
                          5)  Sanitary and well codes
                          6)  Other regulatory tools
                  2.   Development and Redevelopment Policies
                       a) Design and location of services and utilities
                       b) Land rights, acquisition, and open space use
                       c) Redevelopment
                       d) Permanent evacuation
                  3.   Disaster Preparedness
                  4.   Disaster Assistance
                  5.   Floodproofing
                       Flood Forecasting and Waiming Systems and Emergency Plans

                  Strategy B. Modify Flooding
                  1.   Dams and Reservoirs
                  2.   Dikes, Levees, and Floodwalls
                  3.   Channel Alterations
                  4.   High Flow Diversions
                  5.   Land Treatment Measures
                  6.   On-site Detention Measures

                  Strategy C. Modify the Impact of Flooding on Individuals and the Community
                  1.   Information and Education
                  2.   Flood Insurance
                  3.   Tax Adjustments
                  4.   Flood Emergency Measures
                  5.   Postflood Recovery

                  Strategy D. Restore and Preserve'the Natural and Cultural Resources of
                              Floodplains
                  1.   Floodplain, Wetland, Coastal Barrier Resources Regulations
                       a) Federal regulations
                       b) State regulations
                       c) Local regulations
                          (1) Zoning
                          (2) Subdivision regulations
                          (3) Building codes
                          (4) Housing codes
                          (5) Sanitary and well codes
                          (6) Other regulations
                  2.   Development and Redevelopment Policies
                       a) Design and location of services and utilities
                       b) Land rights, acquisition, and open space
                       c) Redevelopment
                       d) Permanent evacuation
                  3.   Information and Education
                  4.   Tax Adjustments
                  5.   Administrative Measures

                                                                                                tection of the natural and cultural resources of floodplain. Today's floodplain
                             GENERAL PRINCIPLES FOR                                             management framework is a product of planned initiatives, evolved methods,
                            FLOODPLAIN MANAGEMENT                                               and fortuitous circumstances. Many aspects of the framework developed
                       The federal government has a fimdamental interest                        independently and then were incorporated for the common purpose. Many
                    in how the nation's floodplains are managed, but the                        were intended at the outset to complement each other. Many apply to flood-
                    basic responsibiliyfor regulatingfloodplains lies                           plains only incidentally but nevertheless serve an important function.
                    with the state and local governments.                                              The idea of a unified national program for reducing flood losses was
                    9 Floodblains must be considered in the context of                          first set out in House Document 465 and has been refined and expanded
                    total community, regional, and national planning                            since to produce A Unjit-ed Natioi@ Programfor Floodplain Management. It estab-
                    and management                                                              lishes as a basic national goal the wise use of floodplains; sets forth the con-
                    e Flood loss reduction should be viewed in the larger                       ceptual framework of a multiobjective approach to use of the nation's flood-
                    context offloodplain management, rather than as an                          plains, including flood loss reduction and natural values protection; identifies
                    objective in itseff                                                         implementing strategies and tools; and recognizes the respective roles of each
                    9 Soundfloodplain management embodies several                               level of government and the private sector in the decisionmaking process.
                    aspects:                                                                           There are four main strategies for reducing floodplain losses. They are
                         0 goals (wise use, conservation, and development                       described in detail in the Unified National Program documents. Each strategy
                         Of resources),                                                         can be carried out by using one or more specified "tools" -activities under-
                         * Objectives (economic efficiincy, environmental                       taken by governments, individuals, or the private sector that have an impact
                         quality, and social well-being),-                                      on floodplain management:
                         0 consideration offuture needs and the role of the                            0 Modify susceptibility to flood damage and disruption.
                         floodblain;                                                                   0 Modify flooding.
                         0 evaluation of alternative strategiesfor alleviat-                           0 Modify the impact of flooding on individuals and the community.
                         ingflood losses,-
                         0 accountingfor benefits and costs and inter-                                 0 Restore and preserve the natural and cultural resources of floodplains.
                         related impacts offloodplain management
                         actions,-                                                                     At all levels of government and within the private sector, the tools and
                           motivation of decisionmakers;                                        strategies for floodplain management take various forms, including compo-
                           coordination of agencies at all Levelsfor all                        nents of broader initiatives, legislation, and policy directives in water resources
                         aspects offloodplain management; and                                   management, emergency management, environmental protection, and proj-
                         0 evaluation through continuous monitoring and                         ects for community development and redevelopment. Federal, state, and local
                         reporting to the public.                                               programs and private efforts to manage the natural and cultural resources of
                                                                                                floodplains are usually focused on the particular resource or activity that hap-
                Source: A Unified National Program for Floodplain                               pens to occur on the floodplain rather than on the floodplain itself
                Management, 1976
                                                                                                                                     The Federal Government
                                                                                                       At the federal level, flood loss reduction is accomplished through a
                                                                                                network of laws, executive orders and directives, administrative regulations,
                                                                                                interagency actions, and agency policies and programs. These components
                                                                                                of the framework address various aspects of floodplain management, includ-
                                                                                                ing insurance, land use, disaster preparedness and relief, information and
                                                                                                education, warning systems, and structural flood control. At least 25 subdivi-
                                                                                                sions of 12 departments and agencies have significant responsibility for some
                                                                                                aspect of floodplain management.
                                                                                                       The water resources values of floodplains are managed through pro-
                                                                                                grams for water quality, pollution control, watershed management, erosion
                                                                                                control, and groundwater and aquifer protection. Restoration and preserva-
                                                                                                tion of the living resources of floodplains have been addressed in multiobjec-
                                                                                                tive federal programs or activities aimed at protecting inland or coastal wet-
                                                                                                lands or barrier islands. Other federal programs have been specifically
                                                                                                directed at protecting habitat. Cultural resources have been protected through
                                                                                                a variety of federally supported programs for open space, recreation, urban
                                                                                                renewal, waterfront redevelopment, and historic preservation.

                                                                                                                                           State Government
                                                                                                       State activities for floodplain management have responded to and often
                                                                                                paralleled federal activities. States administer locally adopted and enforced
                                                                                                floodplain management regulations pursuant to the National Flood Insurance
                                                                                                Program. All coastal states have some type of permitting program for devel-
                                                                                                opment activities below mean high water and most coastal and Great Lakes
                                                                                                states have federally approved coastal management programs. Every state has
                                                                                                a multihazard emergency operations plan that covers floods. All coastal states
                                                                                                and some inland states have wetland protection programs of some sort which
                 78                                                                             include mapping, permitting, and protection.

                                                       SOME COMPONENTS OF THE FEDERAL
                                                  FRAMEWORK FOR FLOODPLAIN MANAGEMENT
                   the Clean Water Act of 1972 0 Coastal Barrier Resources Act (1982) 0 Coastal Zone Management Act of 1972              The
                   Dam Safety Act (1986) 0 The Disaster Relief Act of 1974 0 The Disaster Relief and Emergency Assistance Amend-
                   ments of 1988 0 The Emergency Wetlands Resources Act of 1986 0 The Endangered Species Act of 1973 0 Executive
                   -'Order 12127 (1979) 0 Executive Order 12148 (1977) o Executive Order 11296 (1966) 0 Executive Order 11988 (1977)
                     Executive Order .11,990, 'Protection of Wetlands 0 The Federal Crop Insurance Act (1980) 0 The Federal Insecticide,
                   Jungicide, and Rodenticide Act a Federal Interagency Floodplain Management Task Force established 1975 * The
                   Federal Land Policy and Management Act of 1976 0 Fish and Wildlife Coordination Act of 1958 * The Flood Disaster
                   Protection Act of 1973 0 The Food Security Act of 1985 * House Document 465, A UniftdNational Prograinfor Managing
                   -'Flood Losses - The Housing Act of 1961 0 The Housing-and Urban Development Act of 1969 0 The Housing and Corn-
                   munity Development Act of 1977 0 The Housing and Community Development Act of 1987 0 The Land and Water
                   Oonser-Vatibn Fund,Act    1964) 4@ The Nationa I Dam Insi)ecti6n A:ct,of,1072 0 The National Environmental Policy Act
                   @1969) eThe'National Flood Insurance Act (1968) 0 The National Forest Management Act of 1976 0 The National
                   ''Historic Preservation Act (1966) @@ The North American Waterfowl Management Plan (1986) 0 OMB Memorandum,
                     N6nstruttural Flood Protection Measures and Flood Disaster Recovery" (1980) 0 The Omnibus Budget Reconcili-
                   ation Act of 1981   The Reservoir Salvage Act of 19,60 0 The Safe Drinking Water Act of 1974 0 The Soil and Water
                   Resources Cons6rvation.Act of 1977 *The Tax RefornrAct of 1986 0 United States-Mexico Boundary Treaty of Nc@vem-
                   ber 23,,1970,o The Water   'Bank Act (1970) 0 Water Pollution Control Act Amendments of 1972 a The Water Quality
                   ,Act of 1987 0 The Water'Resources Development Act of 1974@9 The Water Resources Development Act of 1986 0 The
                   Water Resources Development Act of 1990 0 Water Resources Planning Act of 1965 0 The Watershed Protection and
                   Flood Prevent-ion Act of 1954     The Wild, and,Scenic Rivers Act of-1968 0 Flood Control Act of 1917 0 Rivers and
                   Harbors,Act of 1930 a Flood Control Act of 1936

                        Several  states have adopted their own statewide floodplain management
                   regulations,  and in some states executive orders compel state agencies to con-
                   sider flood hazards before carrying out their activities. Several states have
                   adopted environmental policy acts that require analysis of the impacts of
                   proposed state and local actions on natural resources, including those of the
                   floodplain. Every state has an agency involved in planning, funding, or spon-
                   soring structural flood control projects. Floodplain management is further
                   accomplished through state-level regulatory and nonreg-ulatory programs
                   directed at wetlands, dune protection, restoration and protection of living
                   resources and natural areas, mapping, flood conveyance and storage, dam
                   safety, pollution control, natural crops, groundwater supply, wildlife habitat,
                   historic preservation, recreation, and shoreline management.                                                           THEIDNDR
                                                    Local Government                                                     In 1987 the United Nations General Assembly
                                                                                                                         &clared 1990 to 2000 AD as the International
                        The adoption and enforcement of local floodplain regulations is now                              Decade for Natural Disaster Reduction (IDADR).
                   widespread because of the National Flood Insurance Program. Many local                                It is antz@cipated that this assessment will provz&
                   zoning and subdivision regulations protect the natural and cultural resources                         useful input to the United States program for
                   of floodplains through shoreline setbacks, density limits, historic preservation                      the Decade.
                   guidelines, or specification of compatible uses. Local governments are almost
                   exclusively responsible for local drainage and stormwater management. Many
                   localities participate as cosponsors of structural projects, providing a small
                   financial contribution to the cost of the works. Some localities have coastal
                   management programs within a state framework, and some states provide for
                   local application of state controls, usually established under legislation geared
                   toward multiple goals like protection of wildlife and sensitive shoreland areas,
                   or erosion control. Some communities have developed multihazard emergency
                   preparedness or operations plans.

                                                     Regional Entities
                        Regional entities can be extremely effective in managing floodplains,
                   whose boundaries typically do not conform to traditional governmental juris-
                   dictions. Special districts are the most numerous and fastest-growing type of
                   governmental entity in the country; nearly one-quarter of them have natural
                   resource functions-soil and water conservation, drainage and flood control,
                   and sewerage. The nation's 3,000 counties also have floodplain management
                   functions, including storm drainage, land acquisition, flash flood warning,
                   emergency response, land use planning, and building regulation (usually of
                   unincorporated areas). Nearly 3,000 conservation districts exist, covering more                                                                       79

                                                                                than 97% of the country. They provide planning and technical assistance to
                  SELECTED PROFESSIONAL AND                                     individual landowners for controlling soil erosion and water pollution, and
              NONPROFIT ORGANIZATIONS ACTIVE                                    they implement swampbuster, wetland restoration, and erosion reduction
                  IN FLOODPLAIN MANAGEMENT                                      portions of the Food, Agricultural, Conservation, and Trade Act of 1990.
              American Institute of Architects                                                                     The Private Sector
              American   Land Resource Association
              American Littoral Society                                               Besides undertaking basic and applied research on floodplain manage-
              American Planning Association                                     ment, academic institutions also provide education in the field, although so
              American Rivers Conservation Council                              far no university offers a program of study specializing in floodplain manage-
              American   Socieo of Civil Engineers                              ment. Many states have Water Resources Research Institutes, as authorized
              American   Water Resources Association                            by the Water Resources Act of 1964.
              Association of Conservation Engineers                                   Over 700 national and local land trusts exist throughout the nation.
              Association of State Dam Safety Officials                         Most are nonprofit organizations that receive land, either through donations
              Association of State Floodplain Managers                          or purchase, and manage it as open space or for historic purposes.
              Association of State River Managers                                     There are a large number of professional and nonprofit organizations
              Association of State Wetland Managers
              The Coastal Socieo                                                involved in floodplain management. Most are national in scope and accom-                                    Jr
              Coastal Conservation Association                                  plish their objectives through meetings, publications, lobbying, and fostering
              Coastal States Organization                                       professional communication. The number of private conservation and water-
              Connecticut River Watershed Council                               shed organizations is even larger. Usually nonprofit with a broad public
              The Conservation Foundation                                       membership, they are typically directly involved in environmental issues with
              Conservation Law Foundation of New England                        flood loss reduction as an indirect goal or benefit. These citizen-based groups
              Council of State Governments                                      serve a tremendous public education function, are largely unaffected by parti-
              Environmental Defense Fund                                        san politics, and can usually respond to an issue more rapidly than govern-
              The Environmental Law Institute                                   ment agencies.
              Environmental Policy Institute                                          Individuals and for-profit corporations have become more involved in
              Freshwater Foundation
              Friends of the Earth                                              floodplain management since the 1960s, helping develop floodproofing tech-
              Friends of the River                                              niques and materials, automated flood warning systems, geographic informa-
              Land Trust Alliance                                               tion systems, remote sensing techniques, and computerized information
              League of Conservation Voters                                     management.
              National Association of Conservation Districts
              National Association of Counties
              National Association of Home Builders
              National Association of State Recreation Planners
              National Association of Urban Flood Manage-
               ment Agencies                                                                        Modifying Susceptibility to
              National Audubon Society
              National Centerfor Urban Environmental                                                  Damages and Disruption
                Studies
              National Emergency Management Association                         Modifying susceptibility to flood damage and disruption is the floodplain
              National Fish and Wildlzfe Foundation                             management strategy of avoiding dangerous, uneconomic, undesirable, or
              National   League of Cities
              National Organization for River Sports                            unwise use of the floodplain. The tools used to implement this strategy are
              National Recreation and Parks Association                         regulations; development and redevelopment policies; disaster preparedness;
              National   Traits Coalition                                       floodproofing and elevation; and flood forecasting, warning systems, and
              National   Trustfor Historic Preservation                         emergency plans.
              National   Water Resources Association
              National   Waterways Conference                                                                           Regulations
              National   Wetlands Technical Council
              National   Wildlife Federation                                          Regulations have a potentially greater impact on flood loss reduction
              The Natural Areas Association                                     than any other single floodplain management tool and have been widely used
              Natural Resources Defense Council                                 over the last 15-20 years. Development that conforms to regulations is less
              New England Natural Resources Center                              prone to flood damage than pre-existing development.
              North American Lake Management Society                                  Regulation is largely a local government responsibility, but throughout
              The Oceanic Society                                               much of the country there is still widespread resistance to any type of land
              The River Conservation Fund                                       use regulation and concern among jurisdictions that it will be ruled an uncon-
              Save the Dunes Council                                            stitutional "taking" of private property. Effective enforcement often requires
              Sierra Club                                                       more training, personnel, and financial resources than many communities can
              Socieo for Range Management                                       provide. Regulations cannot provide full protection; they have a limited impact
              Soil and Water Conservation Sociey                                on existing buildings and infrastructure already subject to flooding, and they do
              The Sounds Conservancy
              The Trust for Public Land                                         not prevent development in floodplains. In addition, most floodplain regulations
              Urban Land Institute                                              do little to protect the natural resources of floodplains. In fact, to the extent
              Wetlands for Wildlzfe                                             that floodplain regulations allow development in floodplains- even though it
              The Wilderness Sociey                                             may not be subject to damage-they can contribute to the loss of natural and
              Wildlife Management Institute                                     cultural resources. On the other hand, current regulations do provide a de
                                                                        I       facto prohibition on development in wetlands.
              30

                                             Academic Institutions Engaged in Natural Hazards
                                           and Emergency Management Research and Education
                  Arizona State University, Office of Hazard Studies 0 Charleston Southern University, Earthquake Educa-
                  tion Center 0 Brown University, Alan Shawn Feinstein World Hunger Program 0 Clark University, Center
                  for Technology, Environment, and Development 0 Colorado State University, Hazards Assessment Labora-
                  tory 0 Cornell University, Cornell Institute for Social and Economic Research/Program in Urban and
                  Regional Studies 0 Memphis State University, Center for Earthquake Research and Information * New
                  York Medical College, Center for Psychological Response in Disaster Emergencies a New York University,
                  Industrial Crisis Institute 0 State University of New York at Buffalo, National Center for Earthquake En-
                  gineering Research 0 Texas A&M University, Hazard Reduction and Recovery,Center 0 Texas Tech Univer-
                  sity, Institute for Disaster Research,,Wind Engineering Research Center 0 University of Arizona, Office of
                  Arid Lands Studies and Arid Lands Information Center 0 University of California, National Information
                  Service for Earthquake Engineering * University of California, California Earthquake Education Project
                  and Chemical Education for Public Understanding Project 9 University of Central Florida, Florida Sinkhole
                  Research Institute 0 University of Colorado, Natural Hazards Research and Applications Information
                  Center 0 University of Colorado, U.S. World Data Center for Glaciology, National Snow and Ice Data
                  Center * University of Delaware, Disaster Research Center 0 University of Hawaii,'. Pacific Islands Develop-
                  ment Programi Disaster Pre aredness and Rehabilitation Project 0 University of Maryland-Baltimore
                                              'p
                  County, Emergency Health Services Program 0 University of Massachusetts,, Land and Water Policy Center
                  @
                    University of North Carolina, Center for Urban and Regional, Studies 0 University of North Texas,
                    mergency Administration and-Planning Degree Program,*, Uriversity.of Pennsylvania, The Wharton
                  School, Risk and Decision Processes@'Ccnter 9 Universitylof Pittsburgh, Center for Social and Urban
                  Research 0 University of Wisconsin Eitension, Disaster Management Center
                  Source: Natural Hazards Research and Applications Information Cc     nt er

                      The most widespread floodplain regulations are the minimum require-                         Average Losses per 1,000 Flood
                 ments of the National Flood Insurance Program, which must be enacted and                       Insurance Policies on Unregulated
                 enforced by communities participating in the program. The minimum regula-                     versus Regulated Structures, 1978-88
                 tions vary depending upon the risk studies and mapping that have been done                               26
                 in the community, but include                                                                            24 Structures Built
                                                                                                                          22  Bell   tion
                      � permitting for all proposed new development;                                                      20
                      � reviewing subdivision proposals to assure that they will minimize flood                     D.    18
                        damage;                                                                                     E 4'5 16
                                                                                                                          14-
                                                                                                                      0
                      � anchoring and floodproofing structures to be built in known floodprone                      -0    12
                        areas;                                                                                      -0  Z5 to
                                                                                                                    E a
                                                                                                                          8           Structures Built
                      � safeguarding new water and sewage systems and utility lines from                            Z     6          After Regulation
                        flooding; and                                                                                     4-
                      � enforcing risk zone, base flood elevation, and floodway requirements                              2
                        after the flood insurance map for the area becomes effective.                                     0
                                                                                                               Source: FEMA/FIA
                      There are numerous performance and prescribed standards applicable
                 to each of the zones on flood insurance maps. The Federal Insurance Admin-
                 istration has several programs to help states and communities adopt and com-
                 ply with the regulations. Other federal agencies provide technical and plan-                             ENFORCING LAND USE
                 ning assistance and support.                                                                             REGULATIONS IN MAINE
                      Since the 1960s the number of state and local governments exercising                     In 1983 the Maine legislature enacted "Ruk 80K"
                 regulatory authority over floodplain uses has increased markedly, and the vari-               to allow less expensive andfaster enforcenzent of local
                 ety of regulatory approaches has expanded. A given state may directly regulate                land use regulations. Once local code enforcenzent
                 the flood hazard area, set standards for local application, or regulate the flood             officials are trained, they can take a violation directo
                 hazard area as part of a broader resource protection and management pro-                      to the district court without an attorney. Procedures
                 gram. To meet these requirements, local governments adopt specific flood-                     arefolkwed that are lessforinal than usual but
                                                                                                               do not sacr2fice the defendant's due process rights.
                 plain management or stormwater management ordinances and incorporate                          The court can levy afine and order abatenient Of
                 floodplain management provisions into zoning and subdivision regulations,                     the violation.
                 housing and building codes, and resource protection regulations. The number
                 of communities with regulatory requirements more stringent than those of the
                 National Flood Insurance Program is unknown, but clearly is in the thousands.

                                                                                                          Development and Redevelopment Policies
                            THE SOUTH CAROLINA                                              Federal, state, and local governments all have established programs, poli-
                    BEACHFRONT MANAGEMENT ACT                                         cies, and directives to avoid inappropriate development and redevelopment of
                  The South Carolina Beachfront Management Act                        the floodplain.
                  establishes a "no construction" zone beginning at the                     Federal policies relating to the design and location of services and utilities
                  crest of the actual or theoretical dune line and extend-            (roads, bridges, and sewer lines, etc.) in floodprone areas include the National
                  ing landward 20feet or 40 times the average annual                  Environmental Policy Act, Executive Order 11988, and the Coastal Barrier
                  rate of erosion, whichever is greater. The legislature              Resources Act. All of these either restrict federal participation in development
                  anticipated that the Act would result in the gradual
                  elimination of structures built too close to the ocean              in floodprone areas or require careful review of the impacts on the floodplain
                  and hence subject to damage or destruction from                     of proposed federal or federally supported activities.
                  hurricanes and other coastal storms.                                      Several states have issued executive orders or other directives compar-
                                                                                      able to the federal ones, and every state now has a statute or executive order
                                                                                      to govern construction of state projects, such as prisons and universities, that
                                                                                      are exempt from local regulations. All coastal states have policies on develop-
                                                                                      ment in coastal flood hazard areas. Some states have more stringent flood loss
                                                                                      reduction standards for roads and bridges than those of the federal aid system.
                                                                                            In some cases, the only way to preclude future uses incompatible with
                                                                                      the flood risk is to permanently evacuate a portion of a floodplain and to
                                                                                      obtain full title or easements on its development rights. Although this process
                                                                                      (called "acquisition") is expensive, the long-term benefits in reduced flood-
                                                                                      plain losses, protection of natural resources, and public use of the land, may
                                                                                      make it worthwhile.
                                                                                            Most redevelopment relating to flood loss reduction occurs after one or
                                                                                      more major floods. Usually a control structure is built to protect what devel-
                                                                                      opment remains, and a temporary moratorium is imposed to allow evaluation
                                                                                      and planning. Unfortunately, legislative and regulatory requirements often
                                                                                      encourage a quick return to the preflood status quo, wasting opportunities
                                                                                      to mitigate and revitalize the area.

                                                                                                                          Disaster Preparedness
                                                                                            Disaster preparedness encompasses plans for mitigation, warning, and
                                                                                      emergency operations; training; public information activities; exercises to test
                                                                                      disaster preparedness plans; readiness evaluations; research; review and coor-
                                                                                      dination of disaster preparedness plans and programs; and postdisaster evalu-
                                                                                      ations. Individual preparedness is important but severely underutilized. Pre-
                                                                                      paredness plans often are developed in concert with flood forecast, warning,
                                                                                      and emergency plans. There are several federal programs for disaster pre-
                                                                                      paredness, and every state has an integrated emergency management plan
                                                                                      and an agency responsible for preparing for floods. Each Gulf and Atlantic

                                                                                                     SOME FEDERAL PROGRAMS
                                                                                                  FOR DISASTER PREPAREDNESS
                                                      Under the authority of Section 201(d) of the Disaster Relief Act of 1974, the Federal Emergency Management Agency
                                                    provides, up to 50 To matching grants to help states develop and improve state and local plans for preparedness and
                                                    mitigation. Interagency flood hazard mitigation teams are formed after each Presidentially declared flood disaster to
                                                    offer technical assistance to communities and states and to identify mitigation measures that may be implemented in
                                                    the affected areas.
                                                    0 Under Section 409 of the Act, any jurisdiction receiving federal disaster assistance must prepare a hazard mitiga-
                                                    tion plan within 180 daysof the declaration; future federal assistance may be curtailed if such a plan is not filed.
                                                      The Federal Emergency Management Agency, the U.S. Army Corps of Engineers, and the National Weather Serv-
                                                    ice have formed a program of comprehensive hurricane evacuation planning in association with Gulf and Atlantic states.
                                                    The NWS develops the SLOSH (Sea, Lake, and Overland Surge from Hurricanes) model for each coastal basin, and
                                                    FENIA funds the running of the models by the NWS's National Hurricane Center to predict storm directions, speeds,
                                                    and intensities. Evacuation plans are prepared from the studies. Th              'eir value was proved during Hurricane Hugo in
                                                    1989, when hundreds of thousands of people were evacuated and loss of life was kept to a minimum.
                                                    � The Federal Emergency Management Agency provides grants to states to conduct hazard mitigation projects.
                                                    � The Federal Energy Regulatory Commission requires emergency action plans at its licensed projects and periodi-
                                                    caily holds in-depth exercises to test the plans and the licensee's coordination of responsibilities with the appropriate
                                                    state and local disaster agencies.
                                                      The Soil Conservation Service has done flood audits of structures in the floodplain of the Yantic River in Norwich,
                                                    and the Quinnipiac River in Southington, Connecticut, to complement the response to flood warnings.
                                                    0 The U.S. Army Corps of Engineers conducts technical evaluations to determine what types of warning systems and
                32                                  preparedness plans are appropriate for certain areas.

                      coast state has a hurricane preparedness plan completed or underway. Many
                      localities also have emergency management plans, but relatively few have                                                                   LYCOMING COUNTY'S EARLY
                      detailed plans specifically for floods, and even fewer have plans for mitigation                                                                    WARNING SYSTEM
                      after a flood. This is probably due to lack of expertise and funding to develop                                                      Lycoming County, Pennsylvania, lies almost entire@
                      such plans, the hope that the flood problems will be taken care of through                                                           within the drainage area of the West Branch of the
                      some structural measures, and the expectation of receiving federal disaster                                                          Susquehanna River and contains close to 2,200 miles
                      assistance when the flood does occur.                                                                                                of streams. Most of the county's people live on or
                                                                                                                                                           near the river. After major flooding from Hurricanes
                                    Flood Forecasting, Warning, and Emergency Plans                                                                        Agnes in 1972 and Eloise in 1975, a se@f-help early
                             Warning systems and accompanying emergency response have long                                                                 warni .ng system was developed with an initial
                      been recognized as effective ways to save lives and reduce flood damages in                                                          investment of $500. With the help of the National
                      both riverine and coastal floodprone areas. The joint hurricane evacuation                                                           Weather Service, forecasting procedures were estab-
                                                                                                                                                           lishedfor each watershed within the county, and the
                      study is a good example of this. As the cost of the required equipment con-                                                          system was put into operation within three months.
                      tinues to decrease, more and more state and local governments are funding                                                            Over 100 volunteer observers were recruited and
                      the development of flood warning systems and emergency plans.                                                                        trained to observe and monitor stream gages and
                             The National Weather Service conducts research, provides specific                                                             make reports to a stream coordinator The coordina-
                      flood forecast and warning services to over 3,100 communities, and works                                                             tor assembles the data for a watershed and conveys it
                      with many of the 900 communities that have local warning systems. The                                                                to a system coordinator. With the help of expert per-
                      Corps, the Tennessee Valley Authority, and the Bureau of Reclamation collect                                                         sonnel, the d2la is evaluated and a determination of
                      hydrometeorological data and prepare operational forecasts, often in coopera-                                                        expectedflooding and appropriate response is made.
                      tion with the National Weather Service, for their flood control structures. The                                                      Over the last 10 years improvements to the system
                      U.S. Geological Survey collects streamflow and other data that can be used                                                           have been made. To assure adequate backupfor d2t4a
                      for flood forecasting.                                                                                                               transmission, the county provided National Oceanic
                             About half of the states are involved in flood warning, including coop-                                                       and Atmospheric Administration weather radios to
                      eration in IFLOWS (the Integrated Flood Observing and Warning System)                                                                the volunteer observers, and NWS distributed base
                      in Appalachia and installation of automated data collection equipment. Some                                                          station radios to the stream coordinators. In addi-
                      large urban communities have included forecasting and preparedness planning                                                          tion, a system of 10 automated rain gages and 4
                                                                                                                                                           automated stream alarm devices was installed to
                      in their operations for years, participated in regional warning systems, or have                                                     supplement the manual d2ta collection.
                      developed their own systems.
                             University and private research has contributed substantially to the
                      knowledge about and design of warning systems, disaster response, and sys-
                      tem effectiveness. The private sector is vital to the design, installation, opera-
                      tion, maintenance, and modification of local flood warning systems. In many
                      instances, industries have cooperated in the installation and operation of flood
                      warning systems and reduced their own flood losses.

                                                        Floodproofing and Elevation
                             Floodproofing is the use of permanent, contingent, or emergency tech-
                      niques to either prevent flood waters from entering buildings or to minimize
                      the damages from water that does get in. Some of the techniques involve
                      using water-tight seals, closures or barriers; using water-resistant materials;
                      and temporarily relocating the contents of a building. Elevating a structure
                      means raising it on fill, piers, or pilings so that it is above expected flood                                                                Examples of Retrofitting
                      levels. Most new floodplain structures are now designed to incorporate flood-
                      proofing and/or elevation, primarily because it is required by the regulations
                      of all National Flood Insurance Program communities. There are millions                                                                            Reloc-tion: Moving a building to high ground,
                      of existing floodprone homes to which floodproofing could be applied retro-                                                                        above flood levels.
                      actively ("retrofitted"), but this technique is not yet routinely used. One
                                                                                                                                                                         Elevation; Raising a building so that flood waters
                      obstacle has been that flood insurance rates stay the same when a residence                                                                        will go under it.
                      is retrofitted; the new Community Rating System of the National Flood
                      Insurance Program should help remove that disincentive.
                             Floodproofing is probably the tool most widely used by the private sector                                                                   Floodwalls: Building a wall of concrete or earth
                                                                                                                                                                         to keep flood waters from reaching a building.
                      with only limited government assistance. Many of the early floodproofing tech-
                      niques were developed by architects, engineers, and building contractors as                                                                        Dry Floodproofing: Making building walls
                      they worked with individual property owners, especially on small commercial                                                                        wat might and sealing openings so flood waters
                      buildings and industrial facilities. The American Institute of Architects, the                                                                     cancot enter.
                      National Association of Homebuilders, university researchers, and private engi-
                      neering firms have conducted considerable research on and developed techni-                                                                        Wet Floodproofing: Altering a building to
                      cal information about floodproofing. The private sector is also the source of                                                        44            minimice damage when flood waters enter.
                      many floodproofing products, such as vinyl sheathing, devices to prevent sewer
                      backflow, substitutes for sand bags, equipment for filling sand bags, and flood                                                      Source: Floodproof Retrofitting: Homeowner Self-Piolective L!Aavi@,
                      shields to temporarily seal windows, doors, and other openings.                                                                      Shirley Bradway Laska, 1991

                                                                                                                                                                                                                       33

                   FLOODPROOFING AND THE CORPS

                  In the early 1960s the Tennessee Valley Authorio
                  and the US. Army Corps of Engineers jointo pro-
                  duced thefirst comprehensive report on fioodproofing.
                  In 1972, afterfurther review and evaluation of
                  different techniques, the Corps released Floodproof-
                                                                                                                                       P
                  ing Regulations, which has since been incorpo-
                  rated into or recommended by all the major regional
                  building codes and many of the state and local codes.
                  The Corps routinely evaluates the potentialfor using
                  floodproofing in all its project feasibility studies.
                  It also provides technical assistance to local commu
                  nities and is involved in several projects to J70odproof
                  large numbers of homes in communities with chronic
                                                                                                           KY,
                  flood problems.

                                                                                       One floodoroofing technique is to elevate a structure so that flood waters can pass beneath.
                                                                                       Sebastien Roy Elementary School, Verret, Louisiana.

                                                                                              Most states distribute information about floodproofing and provide tech-
                        FLOODPROOFING IN ILLINOIS                                      nical assistance to individuals and groups of property owners. Several states
                  Afterfloodf in Illinois in 1982, 1985, 1986, and                     have promoted floodproofing by publishing technical manuals, helping locali-
                  1987, the state provided technical assistance on flood-              ties obtain funding, holding seminars for industry and individual owners,
                  proofing to victims who visited the local Disaster                   establishing loan programs, and cooperating with disaster assistance centers
                  Assistance Centers. Over W of the flood victims                      so that victims can begin to retrofit immediately. Local governments have
                  eventually altered their houses andloryards to protect               floodproofed individual structures. A few communities have provided their
                  themselves from future flooding. The average                         own funding for larger projects, and others have provided technical and
                  homeowner implemented three different floodproofing                  financial assistance to local businesses and residences.
                  measures. The median costs rangedfrom $42for a
                  standpipe or sewer drain plug to $2,350for sewer
                  backup valves; most cost between 1200 and $600.
                  Most of thefloodproofing measures were installed
                  within two months after thejZood. Those who were                                                    Modifying Flooding
                  flooded again in the 1987floodsfound that their
                  floodbroofing measures were general@y effective.                     Modifying flooding is a floodplain management strategy                         of using structural
                                                                                       means to alter the flood itself Structural measures-dams, reservoirs, dikes,
                                                                                       levees, floodwalls, channel alterations, high flow diversions, spillways, land
                                                                                       treatment measures, shoreline protection works, and stormwater management
                                                                                       facilities-permit deliberate changes in the volume of runoff, peak stage of the
                                                                                       flood, time of rise and duration of flood waters, location of flooding, extent of
                                                                                       area flooded, and velocity and depth of flood waters. The effectiveness of these
                                                                                       measures for protecting property and saving lives has been well demonstrated.
                                                                                       Flood control projects have saved billions of dollars in property damage and
                                                                                       protected hundreds of thousands of people from anxiety, injury, and death.
                                                                                              Throughout the second half of this century, the number and size of
                                                                                       structural flood control projects have been decreasing. High construction costs
                                                                                       coupled with increased cost-sharing requirements for nonfederal sponsors of
                                                                                       projects have made some structures unaffordable. Structural measures also
                                                                                       have been criticized for destroying riparian habitat, scenic values, and water
                                                                                       quality; creating a false sense of security; resulting in eventual loss of flood
                                                                                       storage capacity due to sedimentation; and inducing development in flood-
                                                                                       plains. These criticisms have been coupled with greater recognition that
                                                                                       humans should attempt to adjust to floods and not just try to control them.
                                                                                              It appears likely that the rate of construction of new flood control projects
                                                                                       may hold steady or decrease slightly and that relatively few large flood control
                                                                                       structures will be built in the future. Local and private construction of smaller
                                                                                       flood control projects is certain to continue and may even increase.
                                                                                              One issue that the nation must face in the coming decades is how to deal
                                                                                       with the aging inventory of existing flood control structures. Many darns and
                                                                                       reservoirs are nearing or even past their design lives, and the flood control
              74                                                                       capacity of many reservoirs has been reduced by sedimentation. The financial

                                                                                                                   Expenditures by Federal Water
                                                                                                                       Resource Agencies, 1986

                                                                                                                                        Agencies
                                                                                                                                 Federal

                                                                                                                                 Total  $3.4 Billion

                                                                                                                Corps of Engineers (70%)

                                                                                                                                                     TVA (1%)
                                                                                                       Jl

                                                                                                                                                     scs (8%)
                                                                                                                                       Al
                 4@                        ......

                                                                                                                                             buRec (21%)

                 Structural rmasures to directly control floodwaters have been used on virtually all seiiies-froin modifying a
                 nzql.or river course, such as that of the Colorado, Missouri, or Tennessee, to controlling the flow of (usually)
                 insignificant tributari&.
                 Concrete channel and retaining wal1l, Silver Creek, Leyden Township, Illinois.                         U.S. Army Corps of Engineers
                                                                                                                                 Expenditures
                 resources are not available to undertake all required remedial actions. One
                 option being actively considered and already used on a limited basis by the                                                      od Control (39%)
                 Soil Conservation Service andothers is breaching small dams that are no                                                          Billion
                 longer functional.

                                          Investment in Flood Control

                       The Flood Control Act of 1936 established the federal interest in control-
                 ling floods on the nation's navigable waters and their tributaries. Under this                       Other (61%)
                 Act, $310 million was authorized for carrying out flood control projects, with
                 the Corps receiving major responsibilities for mainstern and downstream
                 projects. The Soil Conservation Service was later assigned responsibility for
                 flood protection on upstream watersheds. This act established the condition
                 that federal involvement in flood control would be appropriate "if the benefits
                 to whomsoever they may accrue are in excess of the estimated costs and if the
                 lives and social security of the people are otherwise adversely affected." For 50
                 years this phrase has been the basis of efforts to analyze the benefits and costs
                 of water resources projects.
                       In addition to the Corps and the Soil Conservation Service, the Bureau
                 of Reclamation and the Tennessee Valley Authority are involved in the con-
                 struction of flood damage reduction structures. The Bureau of Reclamation
                 has planned and constructed many large irrigation and hydropower reservoir
                 projects in the western United States that also provide flood control, including
                 Grand Coulee Dam, the Central Valley Project, and Hoover Dam. The Ten-
                 nessee Valley Authority has played a role in flood control since its creation in
                 1933; two of its statutory purposes are "to improve navigation in the Tennes-
                 see River and to control destructive flood waters in the Tennessee River and
                 Mississippi River Basin."                                                                        WATER RESOURCES DEVELOPMENT
                       Between 1936 and 1975 the federal government spent about $13 billion                                   BY THE STATES
                 for dams and other structures. A few of the first flood control projects were                    0 Florida has created Water Management Districts
                 financed 100% by the federal government, although most required the con-                         that are authorized to levy ad valorem taxes to
                 tribution of land, easements, and rights of way by state and local governments                   finance local waterprojects.
                 and maintenance of the project after it was completed. Today, however, state                     0 In Montana, a water development fund was
                 and local governments and private sponsors are required to share the costs                       created in 1981 to make loans and grants for all
                 of practically all flood control projects.                                                       water development purposes.
                       State and local governments play two major roles in funding water                           Louisiana, Maryland, and Minnesota have
                 resources development: constructing and operating their own projects, and                        recento created programs to Provide financial assis-
                 financing their share of and maintaining the projects built for them by the                      tance to communities that developflood control plans.
                 federal government. Tremendous variations exist in the extent of state and                       a Washington provides grants to communities to help
                 local involvement in each role. As of 1988, 23 states provided technical                         maintain levees and otherfood protection projects.
                 assistance to communities for flood control; many more states are directly
                 involved in local structural flood projects in other ways.
                                                                                                                                                              35

                                                                                  DAMS AND THE FEDERAL GOVERNMENT
                                                The US. Army Corps of Engineers has some responsibility for five categories of dams: dams planned, designed,
                                              constructed, and operated by the Corps; dams designed and constructed by the Corps but operated and maintained
                                              by others; dams owned by other agencies in which flood control storage has been provided at federal expense; dams
                                              for which the Corps issues permits under its regulatory authority; and dams that the Corps inventoried and inspected
                                              under the National Dam Inspection Act of 1972 and the Dam Safety Act of 1986.
                                              0 Upon its creation in 1979, the Federal Emergency Management Agency was given responsibility for coordinating
                                              dam safety The agency coordinates the national dam safety programs and reports progress to the President; chairs
                                              the Interagency Committee on Dam Safety; encourages the development and use of uniform guidelines and stan-
                                              dards; coordinates dam safety research; coordinates the development and funding of training materials; facilitates infor-
                                              mation exchange among federal and state officials; encourages the use of model state legislation and programs; and
                                              fosters preparedness, warning, and evacuation programs.
                                                The Bureau of Reclamation is the coordinating agency for dam safety within the Department of the Interior. In
                                              addition to responsibility for the safety of its own dams, it provides standards and guidelines for the safety of dams
                                              owned or operated by seven other Interior agencies.
                                              * The Tennessee Valley Authority has complete responsibility for the planning, design, construction, operation, and
                                              maintenance of its dams. The TVNs situation is unique in that it constructs its dams with its own resources, and all
                                              except one of its dams are located in a single river basin and operated and maintained for the unified development
                                              and regulation of the Tennessee River system.
                                              0 The U.S. Department of Agriculture, in fulfilling assigned responsibilities to American agriculture, is a permitter,
                                              owner, -manager, planner, designer, constructor, financier, and grantor of dams. Most of the dams are small, but a
                                              few range up to 200 feet high.
                                              * The Soil Conservation Service has provided technical and/or financial assistance for the installation of over 25,000
                                              dams.
                                              0 The U.S. Forest Service owns 1,316 dams and administers permits for an additional 2,366. Most of the owned dams
                                              are designed and constructed by the Forest Service in conjunction with the management of national forests and
                                              grasslands.
                                              0 The Farmers Home Administration, Rural Electrification Administration, and the Agricultural Research Service
                                              also serve on the U.S. Department of Agriculture's Dam Safety Committee and have some involvement with dams,
                                              but generally depend on the Soil Conservation Service for technical assistance.
                                              9 The Federal Energy Regulatory Commission regulates and licenses nonfederal hydropower projects. The commis-
                                              sion is presently responsible for the safety of about 2,000 nonfederal hydropower dams and the Department of Energy
                                              (DOE) has asked FERC to be responsible for dam safety review on 20 DOE dams.

                                                                                                              Dams and Reservoirs
                                                                                   Storing flood water in reservoirs can modify floods by reducing the speed
                                                                             at which the water flows, limiting the area flooded, and reducing and altering
                                                                             the timing of peak flows. However, misconceptions about or lack of understand-
                                                                             ing of dams can create an exaggerated sense of security. Reservoir sedimenta-
                                                                             tion can significantly reduce flood control capacity. Competing uses of the
                      THE DAMAGE PREVENTED                                   reservoir can impair flood control because those relying on the dam for recre-
                     BY FLOOD CONTROL DAMS                                   ation and water supply (irrigators, manufacturers and residential users) often
                jVo accurate number is available of the actual               press for continued high pool levels, resulting in less storage space in the
                number of people protected bj, flood control                 reservoir for flood waters. In addition, most dams are designed for purposes
                dams. Between 1960 and 1985, Corps                           other than flood control, although they do have the temporary effect of flood
                prol'ects prevented an estimated $245 billion                reduction through storage. The availability of water, power, or recreational
                (1985 dollars) in potential flood damages.                   opportunities associated with dams therefore often attracts new development
                Since its inception, the Tennessee Valley                    regardless of the flood risk or the ability of the dam to provide flood protec-
                Authorio multipurpose dam and reservoir sys-                 tion. Over time, without adequate land use regulations, encroachment onto
                tem has preventedflood damages that would                    the floodplain downstream of dams can prevent proper operation of the
                have amounted to nearly @3. 03 billion. These                structure and increase exposure to flooding. Once signs of dam failure
                calculations are based on the assumption that                become visible, breaching often occurs within minutes or a few hours, leaving
                floodplains would have been just as intensively              little or no time for evacuation. The massive volume of water and its high
                or spar'sely developed if there were no structural           velocity will cause severe damage.
                protection. Although this is not necessarily the
                case, there is no way to account for the de-                       More than 20 federal agencies and four independent offices and com-
                velopment that may have been encouraged by                   missions own about 4,000        'dams, have regulatory authority over 6,000 others,
                the presence of the dam. Likewise, it is possi-              and have various other responsibilities for additional tens of thousands of non-
                ble that losses could be greater without dams                federal dams. The number of dams of all types and sizes in the United States
                because development would have taken place in                is unknown, but when small dams (such as for farm ponds) are included, the
                the reservoir area if the dam had not been                   total could be as high as several million.
                built.                                                             State regulation of dams is generally considered to have started in
                                                                             California after the failure of the St. Francis Dam in 1928. The California law
              36

                has been strengthened at least twice since then after other major dam failures
                or near failures, and has been used as model state legislation for the review,                THE CLASSIFICATION OF DAM
                inspection, certification, and maintenance of nonfederal dams. As of 1989, 31                           FAILURE RISK
                states had statutory authority to perform all of these functions, and only two            Classf@ation of the risk of potential dam failure is
                had no statutory authority at all. The states had a collective 1989 budget for            based on the severiy of Potential impact rather Man
                dam safety of $17,668,552. The Association of State Dam Safety Officials,                 the structural safety of a dam. Dams may be of very
                which was organized in 1984, has become a major influence in Improving                    sound construction but classified as "high hazard" if
                state regulation of dams.                                                                 theirfailure, however unlikely, could result in
                                                                                                          catastrophic loss of life. Lower risk classifications
                                      Dikes, Levees, and Floodwalls                                       include dams that pose a "significant hazard"for
                                                                                                          which failure is estimated to result in large property
                     Dikes, including levees and floodwalls, can be thought of as dams built              loss; and those that are "low hazard,"Jor which
                roughly parallel to a stream rather than across its channel, or parallel to the           failure is expected to result in mminial property loss.
                shorelines of lakes, oceans, and other water bodies. Levees are generally con-            Thefailure of several dams during the 1970s led to
                                                                                                          the evaluation and repair of numerous unsafe dams
                                                                                                          in the United States.

                                                                              Nt

                                                        71,

                An estimated 25,000 miles of levees andjloo&vak@ have been built nationwide. They can be very effective in
                reducing_17ood losses, although areas behind levees andfloo&valls may risk greater than normalAod d2mage.
                Floo&vall, Waterloo, Iowa.

                structed of earth, floodwalls of masonry or steel. Levees were probably the first
                structures built for flood control by European immigrants to North America.
                Thelfirst levee in the Mississippi Valley was constructed at New Orleans in
                1717. Levees are the most common type of flood control works. Although they
                can-be effective in reducing flood losses, a large percentage of private or
                locally built levees and floodwalls provide a low level of protection suitable
                only for agricultural purposes or are poorly designed and maintained. Levee
                or floodwall overtopping or failure is involved in approximately one-third of
                all flood disasters.
                     Areas behind levees and floodwalls may be at risk of greater than normal
                flood damage for several reasons. Many floodplain residents in those areas
                believe that they are protected from floods and do not think it necessary to                 LEVEES IN THE UNITED STATES
                take proper precautions. Development may also continue or accelerate based                About 1, 000 communities (5.517o offloodprone
                on expected flood protection. A levee breach or floodwall failure, like a dam             communities) have levees that protectfrom I%
                break, can release a large wave of flood waters with high velocity. After a               annual probabiliy floods; the length of these struc-
                breach, the downstream portion of the levee system may also act like a dam,               tures is about 9,000 miles and they protect about
                catching and prolonging flooding of the once-protected area.                              5,000 square miles of land.
                     The Corps has designed and constructed about 10,500 miles of levees
                and floodwalls, most of which have been assigned to nonfecleral sponsors for
                operation and maintenance after construction. The Federal Emergency Man-
                agement Agency has established minimum design, operation, and maintenance
                  i ro

                standards for levees that, for insurance purposes, must be met in order to be
                credited with providing protection against a 1% annual probability flood. The
                Tennessee Valley Authority owns and inspects 37 saddle dams and levees and
                treats them with the same criteria as regular dams, including inspections,
                instrumentation, and maintenance. Thirteen states have special regulations
                governing the construction of levees.                                                                                               77"

                                                                                                                                    Channel Alterations
                                                                                                   Channel alterations increase the flow-carrying capacity of a stream's
                                                                                            channel and thereby reduce the height of a flood. The various types of altera-
                                                                                            tions include straightening, deepening, or widening the channel, removing
                                                                                            debris, paving the channel, raising or enlarging bridges and culverts, and
                                                                                            removing dams and other obstructions.
                                                                                                   Channel alteration is widely practiced by state and local governments
                                                                                            to control flooding by rapidly conveying storm runoff through populated
                                                                                            locales to downstream areas. The Corps and the Soil Conservation Service
                                                                                            also undertake channel alterations. The Corps projects typically lie on larger
                  Structural techniques to modify channels and control stream               streams and rivers, while Soil Conservation Service works mostly in smaller
                  flow include the construction of diversionary walls and                   streams on the upper portions of watersheds. The Soil Conservation Service
                  gabions-prefabricated baskets of rock within wire cages                   has provided assistance in the construction of 10,700 miles of open channels.
                  used to stabilize banks,
                  City Creek Canyon, Salt Lake City, Utah.                                         The use of channel modifications has decreased primarily because of the
                                                                                            potentially adverse environmental impacts. Alternative designs are now devel-
                                                                                            oped that include less straightening of channels, employ more gradual slopes,
                                                                                            and use natural vegetation or riprap rather than concrete-lined channels. This
                                                                                            minimizes destruction of fish and wildlife habitat, helps maintain water quality,
                                                                                            and avoids undesirable downstream impacts.

                                                                                                                                  High Flow Diversions
                         AN ALTERNATIVE APPROACH                                                   Diversions intercept flood waters upstream of a damage-prone or con-
                      TO STORMWATER MANAGEMENT                                              stricted area and convey them around it through an artificial channel or a
                  The cost to communities of danwges caused by                              designated flow-way. Diversions may either completely reroute a stream or
                  stormwaterflooding and investment in costly chan-                         collect and transport only excessive or potentially damaging flows. A negative
                  nelization and other conduits can sometimes be                            aspect of such diversions is the false sense of security that may prevail in the
                  reduced through different approaches to stormwater                        protected areas along with a lack of awareness that the floodway actually exists.
                  management. In Arizona, for example, the larger,                          Several high flow diversions have been constructed along the Mississippi
                  rapidly urbanizing communities all have someforin                         River. Excess water has also been temporarily diverted from the Great Salt
                  ofstormwater management requirementsfor new                               Lake to an evaporation basin to prevent lakeshore flooding.
                  development. All ofthe larger communities in the
                  state's two urban count2@s, which include 7717o of                                                           Stormwater Management
                  the shate's population, regulate the development of                              Stormwater management is the removal of water that falls directly onto
                  watersheds.
                                                                                            properties as opposed to flood water that flows onto the property from upstream
                                                                                            sources or an ocean surge. Stormwater networks have historically been con-
                                                                                            structed in urban and agricultural areas to remove these waters. Generally,
                                                                                            the stormwater system removes the excess rainfall over a period of days and
                                                                                            the temporary ponding floods only low-lying buildings and roads. A signifi-
                                                                                            cant problem occurs when an agricultural zone with an adequate stormwater
                                                                                            system is urbanized. Large areas are paved with roofs, roads, and parking, con-
                                                                                            tributing to additional runoff. Often, shopping centers and other develop-
                              ON-SITE DETENTION:                                            ments are placed on natural drainageways. The pre-existing stormwater net-
                            A MULTIPURPOSE TOOL                                             work becomes inadequate for its new urban use. Localized flooding then
                                                                                            occurs.
                  Principal on-site detention measures include restrict-                           In an alternative approach often used in new developments today, runoff
                  ing land clearing, creating impervious areas, and                         may be retained on the site, within a regional system, and total runoffwithin
                  providingfor temporary storage of some or all of the                      a watershed may be managed so that discharges from different units reach the
                  runofffrom a property. Many urban communities                             main channel at different times to reduce peak flows downstream. Natural
                  have begun to recognize that areas devoted to storm-                      drainage systems may be used instead of concrete-lined channels or enclosed
                  water management represent a significant portion of                       pipes. Many local ordinances now require a zero-increment runoff for new
                  their open space land and opportunities for urban
                  recreation and wildlife protection. Shallow grass-                        development, making such on-site detention a necessity.
                  covered basins can be used as athLeticfields, parking
                  lots, orfor other purposes during dry periods and as                                                              Shoreline Protection
                  detention basins after storms. Equipping roofs or
                  parking lotsfor temporari@ storing at Least a Part of                            Quasi-natural methods such as beach nourishment or artificial sand-
                  the water thalfalls on them, designing streets in                         dune building are often used to attempt to restore an eroding beach as well
                  hilly areas to prevent rapid runoff incorporating                         as protect development. Long reaches of shore can be protected by artificial nour-
                  small retention basins into landscaping, using rock-                      ishment at a relatively low cost per linear foot. In addition, nourishment can
                  filled pits to catch gutter runoff, and using pave-                       widen a beach and increase its recreational value. A well-known beach
                  ments that let water seep through into the ground                         nourishment project is the 10. 5 miles of beach restoration in Dade County,
                  below all slow runoff.                                                    Florida, which includes Miami Beach. However, these methods provide only
                                                                                            temporary solutions to chronic long-term erosion caused by the diminishing
                                                                                            supply of sediment in the littoral system. They also require periodic renourish-
                38

                      ing during their 15- to 50-year life span. Even so, they are more cost-effective
                      than large structures, such as groin fields or segmented offshore breakwaters.
                      These structures can also build or increase beach width as well as provide
                      protection, but erosion can occur downdrift if they are not properly designed.
                             Structures like seawalls, bulkheads, and revetments protect development,
                      but are not intended to renourish or widen the beach. Erosion can occur in
                      front of them because the natural movement of the shoreline has been affected.
                      Such structures as breakwaters and jetties, which are designed to protect
                      harbors and navigation channels from wave action or to stabilize inlets, can
                      also cause erosion on the downdrift side if they do not include a sand-
                      bypassing system.
                             Because of their high cost, few shoreline protection projects have been
                      built without federal assistance, although most coastal states and many com-
                      munities have participated in various ways. Some states, notably North Caro-
                      lina, have adopted policies against new structural shoreline protection projects,
                      opting to allow the shoreline to retreat naturally. Others, such as Connecticut,
                      discourage construction of new structural projects, but do not specifically pro-                                                                     ADJUSTING TO A
                      hibit them. Still others, such as New Jersey, have active structural protection                                                                RETREATING SHORELINE
                      programs. Some states have empowered localities to establish beach protection
                      districts with the authority to collect taxes to fund long-term maintenance                                                          Where relative sea level rise is accelerating, coastal
                      programs. Private landowners also use various techniques to forestall erosion                                                        flooding and erosion will also accelerate, placing bil-
                      and reduce damages. These measures are necessarily low-cost and small-scale:                                                         lions of dollars worth of additional coastal property
                      vegetation plantings, beach fill, breakwaters, groins, revetments, bulkheads,                                                        at risk. The nation will thus have the options of
                      and seawalls.                                                                                                                        retreatingftom the shoreline, armoring it with pro-
                                                                                                                                                           tective measures, or providing beach nourishment.
                                                                                                                                                           The National Park Service's polky is to allow natu-
                                                          Land Treatment Measures                                                                          ralforces to act on the shoreline rather than trying to
                             Land treatment measures reduce overland runoff from agricultural                                                              prevent erosion with structural devices. The state Of
                      lands to streams or other waters by improving infiltration of rainfall into the                                                      North Carolina has taken a similar stance. Sow
                      soil, slowing and minimizing runoff, and reducing the sedimentation that can                                                         federal agenct@s have limited the use of structural
                      clo stream channels or storage reservoirs. These techniques are most com-                                                            measures onfederal lands, but when it is economi-
                          9                                                                                                                                cally justifiable and environmentally acceptable, they
                      monly used in agricultural areas. They include maintaining trees, shrubbery,                                                         will still construct pro)ects to protect existing coastal
                      and vegetative cover; terracing; slope stabilization; using grass waterways; con-                                                    development. Likewise, many states limit structures
                      tour plowing; conservation tillage; and strip farming. Some measures involve                                                         in undeveloped or light@ developed coastal areas, but
                      building structures to retain or redirect runoff. Several land treatment meas-                                                       continue to permit structural projects to protect exist-
                      ures involve little additional cos. -.0 the farmer, and some, such as no till or                                                     ing development. The Coastal Barrier Resources Act
                      minimum tillage, actually red-.ce costs. Technical and financial assistance for                                                      excluded the use offederalfunds in "undeveloped"
                      the more expensive techniques is often provided through public sources, par-                                                         coastal regions.
                      ticularly programs of the U.S. Department of Agriculture. Although the
                      impact of an individual measure is limited, extensive land treatment pro-
                      grams can effectively reduce flooding in small headwater areas.

                                                                                                                                                                             r

                                                                                                                                                                             V

                                                                                                                                                           Restoration of beach vegetation is one ineans of slowing beach
                                                                                                                                                           erosion and transport,
                                                                                                                                                           Beach grass planting by volunteers to preserve sand dunes,
                                                                                                                                                           Newbugport, Massachusetts,

                                                                                                                                                                                                                       79

                                                                                                              Modifying-t-he Impacts of Flooding

                                                                                                Despite efforts to control flooding and to reduce susceptibility to it, floods
                                                                                                do occur, with adVense-consequences on individuals and communities. A third
                                                                                                strategy for mitigating floodplain losses is to help individualsand communi-
                                                                                                ties prepare for and recover from floods. This can be done through informa-
                                                                                                tion dissemination -and -education, spreading the costs of the loss over time,
                                                                                                and transferring some of the individual losses to the community.
                                                                                                        It is not clear whether the present combination of flood insurance, dis-
                                                                                                aster assistance, tax adjustments, and postflood recovery practices designed to
                                                                                                implement this strategy is producing an equitable sharing of the capital and
                                                                                                operating costs of floodplain occupancy among its beneficiaries, or shifting the
                                                                                                costs from the individual -to -the public and government -agencies. Neither has
                                                                                                there been a clear statement of how much, if any, of the cost of floodplain
                                                                                                development should properly be borne by the general public. Some argue that
                                                                                                all costs should be borne by those occupying the floodplain; others that devel-
                                                                                                opment of the floodplain-provides economic benefits and, therefore, the
                                                                                                general public should shoulder them.

                                                                                                                                   Information and Education
                                                                                                        Information and education activities for floodplain management have
                                                                                                expanded dramatically since the 1960s, as illustrated by the number of publi-
                                                                                                cations, technical manuals, brochures, conferences, workshops, organizations,
                         SIR                                       W,                           and media presentations now in existence. The effectiveness of this activity is
                         U.
                                                                                                difficult to assess. It is clear that many local officials and property owners still
                         IL
                         0
                                                                                                do not thoroughly understand concepts of probability, cumulative impacts,
                                                                                                off-site impacts, and functional values-all of which are important for success-
                                                                              S                 ful floodplain management. It is also clear that little of the material that has
                                'S
                      Gul       S                                                               been generated and released adequately integrates the flood loss reduction
                            t   i
                    bappe jo                                                 @o
                                                                                                and natural resources protection aspects of floodplain management.
                    Much information on floodplain management andflood                                  Much of the basic information about floodplain management was devel-
                    hazard mitigation has been published in illustrated, clearly                oped or sponsored by federal agencies, and includes technical design and appli-
                    written manuals directed toward both private proper@y                       cation manuals, research reports, computerized databases, and public awareness
                    owners and public offia@ls.                                                 materials. Federal and state agencies train their own personnel in floodplain
                                                                                                management programs and activities. Both levels of government have actively
                                                                                                provided financial and technical support to hundreds of conferences, seminars,
                                STATE INITIATIVES TO                                            and workshops on every aspect of floodplain management for professionals at
                                EDUCATE THE PUBLIC                                              all levels of government and the private sector, and for floodplain residents.
                                                                                                        In addition, states respond to individual inquiries from local officials,
                      Texas holds workshops on the National Flood                               insurance agents, lenders, property owners, and the general public, and pub-
                    Insurance Program tailored to the host county'sflood                        lish information tailored to the particular legal, administrative, and geo-
                    situation, and invites lenders, insurance agents, real                      graphic situations of each state. Numerous nonprofit and professional organi-
                    estate agents, and others.                                                  zations with concern for floodplain management have been formed in the last
                    0 In Tennessee, a community planner will visit a                            two decades. These organizations conduct research, produce publications,
                    floodprone site upon request, recommend actions, and                        hold conferences and workshops, and provide a network through which
                    direct the owner to more information or assistance.                         professionals can exchange information.
                    0 Wisconsin state law requires real estate agents to
                    advise prospective Purchasers if a properly is shown                                                                      Flood Insurance
                    as floodbrone on ATIP maps.
                      The Maryland Department of Natural Resources                                      Insurance is a mechanism for spreading the cost of losses both over
                                                                                                time    and over a relatively-large number of similarly exposed risks. Until 1969,
                    created "Farley Floodhound," a cartoon character
                    who appears in a coloring book and helps 'flood                             insurance against flood losses was generally unavailable. Under the National
                    pups" learn flood safety tips.                                            --Flood Insurance Program, initiated in 1968 and significantly expanded in
                    a Arizona is preparing a short course to be presented                       1973, the federal government made flood insurance available for existing
                    at local real estate schools.                                               property in flood hazard areas in return for enactment and enforcement of
                                                                                                floodplain management regulations designed to reduce future flood losses.
                      The Oklahoma legislature passed a law in 1986                                     Although participation in the program is voluntary, of 21,926 communi-
                    that reads, ",@f the premises to be rented have been                        ties in the nation identified as floodprone, 18,023 (82%) had joined the pro-
                    flooded within the pastfiveyears and such fact is                           gram as of November 30, 1990. At the end of calendar year 1990, there were
                    known to the landlord, the landlord shall include                           2.39 million policies in force with $201 billion of coverage. From 1978 through
                    such information prominently and in writing as part
                    of an                                                                       1989, over 384,000 claims were paid totalling over $3.1 billion. Net receipts
                         y written rental agreements."                                          from policy premiums versus                  Iclaims payments varies substantially from year
                                                                                                to year. From 1978 to 1989 the net operating deficit or surplus rangedfrorn a,-

                40

                    deficit of $261 per policy in 1979 to a surplus of $98 per policy in 1987. A sur-
                    plus was realized in fiscal years 1986, 1987, and 1988. As of October 1, 1988,                                                              NFIP Flood Claims Paid
                    -the flood insurance fund was operating with a ne@t surplus of $450 million, the                                                            1978-1987
                    result of a combination of rate increases and relatively low flood losses during
                    those years. The accumulated surplus provides a reserve for years with cata-                                                                                   Amount of
                    strophic losses.                                                                                                         State'                                Claims Paid
                          In 1983, the      Federal Insurance Administration initiated its "Write-Your-
                    'Own" program whereby private insurance companies, under special arrange-                                                Alabama                               87,805,791
                    ments, are permitted to-sell and service flood insurance under their own names.                                          Alaska                                  332,839
                    The success of this program is evidenced by the fact that -80 % -of all flood                                            Arizona                               14,064,010
                    insurance is presently sold by the participating WYO insuranc                       Ie companies.                        Arkansas                              10,800,307
                          Insurance premiums are based on the location of a-struatire within the                                             California                            108,846,266
                    flocidplain and are determined rimarily by the hei t of the structure's lowest                                           Colorado                              3,223,467
                                                              p                         - 94 - @ . - -                                       Connecticut                           34,906,126
                    floor in relation to the -height of water during a base flood. Higher rates apply                                        Delaware                              1,929,167
                    to structures subject to fast-moving waters. New and substantially improved                                              District of Columbia                    101,518
                    structures in the floodplain that are not properly elevated to the base flood                                            Florida                               165,125,349
                    level are subject to higher rates than structures already in the floodplain at the                                       Georgia                               8,455,396
                    time a community joined the program. Since 1974,-flood insurance rates have                                              Guam                                      17,492
                                                                                                                                             Hawaii                                10,354,101
                    increased several times in order to reduce the amountof the federal subsidy                                              Idaho                                   499,193
                    and bring the cost of flood insurance closer to true actuarial rates. In early                                           Illinois                              81,307,867
                    1988 the administrator of the Federal Insurance Administration announced                                                 Indiana                               13,289,339
                    success in "making the. National Flood Insurance Program self-supporting                                                 Iowa                                  3,101,421
                    for the historical average loss year." Even so, the existing premium base is not                                         Kansas                                12,957,557
                    large enough to pcrinit the National Flood Insurance -Program to operate on                                              Kentucky                              48,913,951
                    a fully actuarial basis.- But because only 15% to 30% of the nation's floodprone                                         Louisiana                             502,019,965
                    structures are insured, there is plenty of room for increased market penetra-                                            Maine                                 15,921,597
                                                                                                                                             Maryland                              21,859,402
                    tion. Several strategies for increasing the number of insured structures have                                            Massachusetts                         40,890,955
                    been suggested, including requiring more stringent enforcement by lenders                                                Michigan                              23,999,710
                    of the mandatory- purchase requirements, increasing public awareness of the                                              Minnesota                             16,518,655
                    flood hazard, imposing disclosure requirements on-real-estate agents, offering                                           Mississippi                           108,496,982
                    special insurance coverage and policy riders, and maintaining premiums at                                                Missouri                              113,043,717
                    more affordable levels.                                                                                                  Montana                               11943,610
                                                                                                                                             Nebraska                              9,460,795
                          Concern has been expressed that flood insurance-prem                      -ium costs have                          Nevada                                1,891,589
                    increased to a level so high that many people do not purchase flood insurance                                            New Hampshire                         3,729,914
                    -unless they are required to do so by a mortgage lender or unless they have                                              New Jersey                            117,979,379
                    experienced flooding.- Many of those who do purchase                      insurance allow it to                          New Mexico                              490,587
                    lapse later. The net. result appears to be that only- those individuals with the                                         New York                              105,271,504
                    greatest risk actually purchase and maintain flood insurance. To maintain                                                North Carolina                        15,495,792
                    actuarial rates for-this group, insurance rates may beforced even higher.                                                North Dakota                          9,786,873
                          Many of the claims paid out each year are on strixtures that have previ-                                           Ohio                                  29,549,982
                                                                                                                                             Oklahoma                              60,986,298
                    ously incurred damage.. The Federal Emergency Management Agency defines                                                  Oregon                                2,404,346
                    these as-repetitive loss-structures-those for which two or more losses of more                                           Pennsylvania                          61,971,275
                    than $1,000 (build      -ing and contents combined) have been paid during the most                                       Puerto Rico                           32,200,608
                    recent 10-year period. From January 1980 through December 1989, 2 7.5 % of                                               Rhode Island                          7,828,172
                    the total losses and 32.5 % of the amount paid on them were repetitive losses.                                           South Carolina                        10,324,333
                    Most repetitive losses are suffered by structures built before regulations and                                           South Dakota                          1,403,419
                                                                                                                                             Tennessee                             8,482,208
                    are for relatively -small amounts; the building damage is usually a low pe                                -r-            Texas                                 575,588,046
                    centage-of the building value (53.2% of repetitive losses are- for                    10,70 or less                      Utah                                  4,439,661
                    of the building value). A high proportion of the repetitive loss claims pay-                                             Vermont                               1,140,338
                    ments are for contents.                                                                                                  Virgin Islands                        2,332,664
                          Repetitive losses tend to be concentrated in a s               mall   number of National-                          Virginia                              59,077,329
                    Flood Insurance Prograrn communities, and many occur outside the.desig-                                                  Washington                            13,196,518
                    nated floodplain. Six repetitive loss communities have had 29.7 % of all the                                             West Virginia                         67,738,531
                    repetitive losses; 20 communities have had 44.3176 of the losses. Although 12                                            Wisconsin                             3,295,144
                    of the top 20 repetitive loss communities are coastal, only two have significant                                         Wyoming                               1,038,852
                                                                                                                                             Totals                          2,657,819,907
                    numbers of policies in coastal areas. Only 2 2 of the top 100 repetitive loss. -
                    communities are primarily subject to tidal flooding.. Because of this it is                                           Source. Flood Insurance Producers National Committee
                    believed that the repetitive loss problem is more related to riverine or storm-                                       1 "State," as defined by FENIA program regulations,
                    water floodin than to tidal flooding.                                                                                 means any state, the District of Columbia, the territories
                               -     9                                                                                                    and possessions of the United States, the Commonwealth
                          The Federal Insurance Administration has implemented-a Community                                                of Puerto Rico and the Trust Territory of the Pacific
                    Rating System to encourage communities to go beyond the required standards.                                           Islands.
                    the incentive will be a reduction in flood insurance premiums for policy-
                    holders within communities that take approved actions to reduce flood losses.
                                                                                                                                                                                                 41

                     Amount Paid for NFIP Losses,                                                                      Top 20 Repetitive Loss Communities
                                      1980-1989                                                                                      by Number of Losses
                               Total Paid'= $2.27 Billion                                                                   January 1980-December                           1989

                                                      Repetitive Losses (33%)

                                                                                                                                                                                                           York,
                                                                                                                                                                                               e         .1,256
                                                                                             12. S@ i
                                                                                                   x@lom@'Conty, @/                                                                      Towns 1 of Wayne,
                                                                                                     liforhia - 604                                           17. eoi       Co'nty,                 ey - 742
                                                                                                                                                                   Ilin i   51
                                                                                                                                                   6. SSin Chad Co          n
                                                                                                                                                      Missouri - 2,                                't
                                                                                                                                                      Saint Louis C
                                                                                                                                                       Miss
                                                                                                                          3 City of Hou   t n, ex             6       Cit of K4obile,_V
                                                                                                                           IlHa                                             y
                                                                                                                          41 Ha           ty, Texas - 2,37            A a arna, - tm
                                                                                                                                                                            b
                                                                                                                             Ga   eston County, Texas - 544
                     Nonrepetitive Losses (67%)                                                                          16. City f Texas City, Texas       5 t24
                                                                                                                        20.  Mont              unty, Tex                                ity f Saint Petersburg,
               Source: FEMA/FIA                                                                                                                                                        lori   -533
                                                                                                                                                            1. Jefferson Parish, Loui *        -7,871
                                                                                                                                                            2. Orleans Parish, Louisia       -5,153
                                                                                                                                                            8. St. Bernard Parish, Louii       a - 987
                                                                                                                                                            10. City of Gretna, Louisiana - 674
                                                                                                                                                            11. City of Kenner, Louisiana - 605
                                                                                                    Source: FEMA/FIA                                        19. East Baton Rouge Parish, Louisiana - 483

                                                                                                                                                                                5. Puerto Rico - 2,348

                              ACCEPTING THE NFIP                                                      Today, flood insurance is largely unavailable except under the National
                     During the first 15 years of the National Flood                           Flood Insurance Program. An exception is a Lloyds of London-based policy
                     Insurance Program, communities often challenged it                        which has as many policyholders in Utah as does the National Flood Insur-
                     and resisted adopting the required regulations. Now,                      ance Program. Some private policies or riders are available for basement
                     because communities have seen the regulations sup-                        flooding; these were initiated after the National Flood Insurance Program
                     ported in the courts, because there has been intensive                    limited its coverage for basements and subsurface flows. Flood insurance is
                     media coverage offlood disasters, and because con-                        included as part of a comprehensive flood insurance policy for some large
                     cerns about local habihy for flood damages have                           businesses with offices and land holdings in many locations, in and out of the
                     been heightened, there is increased awareness of the                      floodplain. Crop insurance available under the U.S. Department of Agricul-
                     program's benefits. As a result, NFIP regulations                         ture's Federal Crop Insurance Corporation provides protection to agricultural
                     and otherfloodblain management activities have                            producers from losses caused by insects, disease, fire, hail, drought, floods,
                     become institutionalized, and generally accepted as                       freeze, and wind.
                     a community responsibility.
                                                                                                                                            Tax Adjustments
                                                                                                       Most provisions of federal, state, and local tax codes are designed to
                                                                                                encourage development without regard to whether it might take place in a
                        TAX POLICIES TO MODIFY THE                                              floodprone area, while relatively few provisions provide incentives to leave
                              IMPACTS OF FLOODING                                               land in its natural state. Some tax-based incentives for development are
                     In 1987 Des Plaines, Illinois, began a permit                              reductions in property taxes, abatement or deferral of taxes to entice or retain
                     surcharge of $200forfloodplain development projects                        businesses in an area, and the establishment of enterprise zones or other spe-
                     to helpfinance city flood protection activiti@s.                           cial business zones to promote development and employment in economically
                     0 The city of Stamford, Connecticut, has required                          depressed areas. These make locating businesses, homes, and other develop-
                     developers of certain projects constructed in theflood-                    ment in some floodprone areas financially feasible and even attractive. On top
                     plain to contribute funds for the operation and main-                      of this, the federal Internal Revenue Code and many state codes also provide
                     tenance oftheir automatedflood warning system.                             casualty loss deductions on income taxes to those suffering flood losses. After
                     0 After disastrous flooding in 1982, the state of                          disastrous floods, many states and localities provide additional types of tax
                     Connecticut enacted special Ao d relief legislation                        relief, reducing or temporarily suspending real estate taxes or business taxes
                     that included a provision for tax abatements for those                     for those affected by flooding, for example.
                     whose property was damaged more than 10 5o' of its                                Still, more integration of tax policies and floodplain management is
                     value. Towns were authorized to abate up to one-                           occurring. The Tax Reform Act of 1986, for example, made major changes
                     third of the taxes due, and the state would reimburse                      in the Internal Revenue Code, some of which have an impact on floodplain
                     thernfir 90 % of the taxes lost. Eighteen towns                            management. Individual casualty loss deductions under $100 are now pro-
                     offered some tax abatement to property owners, and
                     the state reimbursed the towns a total of $49,504.                         hibited, and the deduction is limited to the portion of the loss that exceeds
                                                                                                10 7o of the adjusted gross income. The new rule does not apply to business
                                                                                                property. The Act also eliminated or restricted many of the tax deductions
                                                                                                and credits that had been used as incentives to build in floodplains, on barrier
                                                                                                islands, and at other hazardous locations.
                 42

                                        Flood Emergency Measures
                     Flood emergency measures are typically carried out by local civil defense,                                               Al
                police and fire departments, public works agencies, and public health person-
                nel, supplemented as necessary by assistance from state and federal agencies.
                Emergency activities during and immediately after a flood may include
                removing people and property from areas about to be flooded; sandbagging
                around individual structures and constructing emergency dikes to direct water
                away from vulnerable areas; search and rescue; and steps to protect the health
                and safety of residents.
                     To be successful, flood emergency measures must have the thorough
                involvement of the private sector, from individuals who evacuate and take                   Emergemy response toflooding is usually the responsibiliy
                                                                                                            of local agencies, with supplemenW assistancefrorn state
                household-level emergency precautions, to the organized group efforts like                  andfederal agencies. However, private citizens are @ypicat-
                those of the American Red Cross local chapters. Private contractors work for                ly the first to respond and provide assistance to others.
                communities and individuals to remove debris and repair homes, roads,
                bridges, and other property damaged from floods. Some states have standing
                contracts with private businesses to provide emergency services in disasters.
                The 1983 floods in Utah showed what literally thousands of volunteers, acting
                individually and in groups, can accomplish during flood emergencies.
                     The Corps is the federal agency most commonly involved in flood emer-
                gencies, under authority of P.L. 84-99, which authorizes it to help in flood
                fighting, repair and restoration of flood control works, provision of emergency
                water supplies, implementation of advance protective measures, and the per-
                formance of other hazard mitigation activities. The support may take the form                     FIGHTING FLOODS IN UTAH
                of technical assistance, materials, equipment, or services. The Soil Conserva-              In ear@ May 1983 Salt Lake County, Utah, began
                tion Service may also become involved with emergency efforts. The Federal                   24-hour monitoring of critical streams in anticipation
                Energy Regulatory Commission requires emergency action plans for all its                    Of severeflooding as a result of a large snowpack and
                licensed dams. The Federal Emergency Management Agency helps state and                      unusually cold spring. The most vulnerable flooding
                local governments assess the extent and severity of damage in order to seek                 location was identzfied as 13th South, where three
                disaster assistance. State emergency services agencies generally coordinate state           streams came together. Ciyforces, with assistance
                resources and activities during flood emergencies, and the state police and                 from volunteers, built temporary dikes along the street
                transportation or public works departments, the state national guard, and the               so it could be used as a channeL After a sudden
                agencies responsible for dam safety and water resources also play major roles.              thaw on May 26, the county and city declared an
                                                                                                            emergency andflood control plans were activated.
                                              Disaster Assistance                                           Two days later another creek reached a flood dis-
                                                                                                            charge nearly double its previous record and went out
                     Disaster assistance is provided by federal, state, and local governments,              Of control. Volunteers were called in to sandbag 1.5
                and the private sector. It may take the form of financial relief, or of help to             miles of State Street through the ciy,- flood waters
                repair, replace, or restore facilities damaged or destroyed by a disaster. The              were successfidly controlled in this temporary river.
                system is most often efficient and adequate to provide the necessary financial              During the extended period offlooding and subse-
                relief to individuals and communities.                                                      quent cleanup in Utah in 1983, volunteers put in an
                     The greatest source of federal disaster assistance is provided under the               estimated 50, 00 0 days of work in Sah Lake City,
                Disaster Relief Act of 1974 and takes the form of grants to the states from the             and about 100, 000 days in the rest of the couny.
                                                                                                            The value of the volunteer work has been estimated
                President's Disaster Relief Fund after Presidentially declared disasters. The               at over $18 million.
                assistance is administered by the Federal Emergency Management Agency,
                which also directs and coordinates the disaster assistance functions of all
                federal agencies. The Small Business Administration issues its own disaster
                declarations and makes low-interest loans available directly to eligible indi-                   =311I.-E.-M".
                                                                                                                  N" .",axg,
                viduals and businesses to replace or repair damaged real estate, inventory,                        ion
                or other business property. The Federal Highway Administration provides
                funding assistance for damaged highway facilities that were constructed with
                federal aid. Under the Emergency Watershed Protection Program, the Soil
                Conservation Service may directly undertake emergency work such as clear-
                ing debris from channels and stabilizing streambanks. As mentioned above,
                the Corps has authority to provide assistance for disaster the Corps has
                authority to provide assistance for disaster preparedness, advance protective
                measures, rehabilitation of flood control works damaged or destroyed by                     State Street, Salt Lake City, Utah, May 1983. (Street
                flood, protection or repair of federally authorized shoreline protection works              was used as a temporary water conveyance path.)
                threatened or damaged by coastal storms, and provision of emergency drink-
                ing water. The Farmers Home Administration State Director may make
                emergency loans to farmers, ranchers, and oyster planters. Under the Emer-
                gency-Conservation Program, an Agricultural Stabilization and Conservation
                Service State Director may designate areas eligible for cost-sharing grants of
                up to 64% to rehabilitate farm lands damaged by natural disasters.
                                                                                                                                                       73

                                                                                                            Although all state and most local governments have programs to coor-
                                                                            			 dinate and provide assistance during an emergency, few have special funds for
                                                                                               financial assistance to victims. Most states limit their own disaster assistance
                                                                                               funding to local governments, rather than extending it to businesses or indi-
                                                                                               viduals. All states now contribute some of the nonfederal share of assistance
                                                                                               for Presidentially declared disasters. States may also declare their own emer-
                                                                                               gencies or disasters; 28 states then provide assistance to localities out of a
                                                                                               governor's emergency fund.
                                                                                                       Local governments may provide disaster assistance to their residents and
                                                                                               business community, most commonly through some form of tax break. Many
                    Most federal disaster assistance is provided through                        localities have joined mutual aid agreements with nearby communities to pro-
                    FEMA, although the Small Business Administration,
                    Federal Highway Administration, Soil Conservation Serv-
                    ice, Army Corps of Engineers, Farmers Home Adminis-
                    ration, and Agricultural Stabilization and Conservation                                       Dollars Paid for Disaster Assistance, 1965-89
                    Service also administer programs. State and local govern-                                       All Disasters versus Floods and Hurricanes
                    mens, as well as private, nonprofit organizations such as
                    the Red Cross, are also centrally involved in providing aid                             1700
                    following flooding.                                                                     1600            Type of Disaster
                    Disaster Assistance Center, DeRidder, Louisiana, 1983.                                  1500
                                                                                                            1400   All Disasters (Total = $6,735,868,000)
                                                                                                            1300   Floods & Hurricanes (Total                       $5,185,337,000)
                                                                                                            1200
                                                                                                            1100
                                                                                                            1000
                                                                                                             900
                                                                                                             800
                                                                                                             700
                                                                                                             600
                                                                                                             500
    								                                                         400
                                                                                                             300
                          THE "AVERAGE" DISASTER                                                             200
                                                                                                             100
                    A 1990 preliminary report by the U. S General
    		    Accounting Office noted that in an "average" dis-
                    aster about 2,000 individuals and families seek fed-
                    eral disaster assistance and the Federal Emergency                           Source: FEMA                                          Year
                    Management Agency spends about $10 million.

                                                                                                            Number of Presidentially Declared Disasters, 1965-89
                                                                                                                  All Disasters versus Floods and Hurricanes

                                                                                                            55-                                               Type of Disaster
                                                                                                            50-                                            All Disasters (Total = 657)
                                                                                                            45-                                            Floods & Hurricanes (Total                    508)
                                                                                                            40-
                                                                                                            35-
                                                                                                            30-
                                                                                                            25-
                                                                                                            20-
                                                                                                            15-
                                                                     A

                 44                                                                                Source: FEMA                                         Year

                      vide equipment, personnel, and other disaster assistance. Research has shown
                      that local governments have the capacity to assume a much higher proportion                                                          NAGS HEAD PLANS ITS RECOVERY
                      of losses than they usually do within the existing framework of federal and                                                                  FROM A FUTURE FLOOD
                      state programs.                                                                                                                    The Town of Nags Head, formerly a quaint village of
                             A number of national voluntary organizations provide disaster relief                                                        seaside cottages on the Outer Banks of North Caro-
                      services, primarily emergency shelter, food, clothing, and medical aid. Some                                                       lina, is now a resort communityfacing substantial
                      also provide longer-term assistance, such as rebuilding homes or job place-                                                        growth and development. One of its main concerns is
                      ment. A committee known as the National Voluntary Organizations Active in                                                          protecting the quality of its natural resources and
                      Disaster coordinates 11 private relief groups. Three of these organizations, the                                                   preparing its res&ents and thousands of visitorsfor
                      American National Red Cross, the Salvation Army, and the Mennonite Dis-                                                            hurricanes and coastal storms. With guidancefrom
                      aster Service, were formally recognized in the Disaster Relief Act of 1974 and                                                     the states Coastal Area Management Act Program,
                      have signed memoranda of agreement with the Federal Emergency Manage-                                                              Nags Head began preparing a local land use plan
                      ment Agency formalizing the provision of their disaster assistance. In addition                                                    that would incorporate a Prisorm mitigation pro-
                      to national organizations, local churches and other voluntary groups often                                                         gram, warning and preparedness plans, and post-
                      provide significant assistance during and after disasters.                                                                         storm reconstruction polky.
                                                                                                                                                         In developing its plan, Nags Head surveyed all its
                                                                Postflood Recovery                                                                       properties at ri@k, finding that 84 01o of the town's
                                                                                                                                                         2,500 buildings lay in the 100-yearfloodplain and
                             Postflood recovery work, aided by many types of disaster assistance,                                                        44 % in the high hazard areas. There were also four
                      has been largely effective at restoring flood-damaged communities and indi-                                                        pub& buikiings, 27 miks of streets, and 32 miles of
                      vidual properties to their preflood condition. Unfortunately, this has not                                                         public waky mains within thefloodblain.
                      always been the wisest course of action, because returning to the status quo                                                       After a series of meetings and workshops, the Board
                      leaves the door open for a repeat of the disaster. Numerous recommendations                                                        of Commissioners adopted policies and actions "to
                      have been made over the years to alter recovery procedures to take advantage                                                       reduce, to the extent possible, future damageftom
                      of the opportunities presented immediately after a flood, when outside exper-                                                      hurricanes and severe coastal storms." There are 12
                      tise and money flows into a community, damaged or destroyed facilities are                                                         miliganim policies, including using the capital
                      waiting to be repaired or replaced, and local attitudes toward mitigation are                                                      imoovernents program to encourage growth away
                      more flexible than before. It was thought that this would be the best time to                                                      from high hazard land into pub& open space, and
                                                                                                                                                         opposing construction offinger canals and other
                      identify mitigation actions that might easily be taken and to delay reconstruc-                                                    prol.ects that destroy the protection proviiied by natural
                      tion until wise decisions about the vulnerability of future development could                                                      features.
                      be made. Gradually federal agency policies began to change so that over the
                      past two decades individuals and communities have had to meet certain con-                                                         The poststorm reconstruction policies are designed to
                      ditions in order to receive disaster assistance. These include protecting the                                                      take advantage of the natural land clearance provided
                      environment, implementing floodplain management measures, purchasing                                                               by severe storms. When it begins to redevelop the
                                                                                                                                                         cleared arms, the town will limit reconstruction of
                      flood insurance, and taking action to mitigate hazards. Passage of the Disaster                                                    substanti@ damaged buildings and public utilitiis,
                      Relief and Emergency Assistance Act in 1988, which allows federal disaster                                                         will rebuild public structures strong enough to be used
                      assistance funds to be spent on mitigation activities and not just to rebuild to                                                   as shelters, and will not permit ocean(ront reconstruc-
                      the predisaster condition, signalled a new approach to postflood recovery.                                                         tion until the state reestablishes the setback line.
                                                                                                                                                         (Adaptedfrom ASFPM News & Views, 1988)
                                            Restoring and Preserving the
                      Natural and Cultural Resources of Floodplains

                      The strategies of preserving and restoring the water resources, living resources,
                      and cultural resources of floodplains are generally intertwined. The best way
                      to protect these floodplain resources is to avoid development within flood-
                      plains. It has been suggested that stronger federal support of programs to set
                      aside floodplains from development is needed, and that federal policies and
                      procedures actually do not encourage and sometimes even obstruct innovative
                      approaches to preserving natural floodplains. Several federal policies, for
                      example, limit the features of water resources projects to those that have
                      quantifiable economic benefits. Because many natural and cultural resources
                      are difficult to quantify, or add only incremental benefits, the cumulative
                      effect of eliminating these features may not be taken into account.
                             Limited preservation and restoration can be accomplished indirectly
                      through flood loss reduction activities. Numerous programs at all levels of
                      government establish policies that encourage, but generally do not require,
                      protecting floodplain resources. Natural resources management itself is usu-
                                                                                                                                                         It has been difficult to quantify the value of the natural
                      ally not focused on floodplains but instead addresses a particular resource                                                        and cultural resources of J76odolains and therefore difficult
                      throughout its natural range.                                                                                                      to justify government expenditures to preserve floooplains
                                                                                                                                                         in their natural state. However, there is a growing desire
                                                                                                                                                         among the public to make sure that the natural bene/ns of
                                                                                                                                                         the riparian environment are safeguarded.
                                                                                                                                                                                                                       75

                                                                                                                                  Regulations
                                                                                             Regulatory measures are among the most widely used and most effective
                                                                                      means of helping to protect the natural and cultural resources of floodplains;
                                                                                      they are employed at all levels of government. There are several drawbacks to
                                                                                      using them, however. Restrictions on the use of private land in order to pro-
                                                                                      tect natural resources are generally viewed less favorably by the public and the
                                                                                      courts than are restrictions to protect human lives or property. Because of
                                                                                      this, regulations must be well designed to avoid being ruled unconstitutional
                                                                                      takings. Finally, protective regulations sometimes conflict with flood loss
                                                                                      reduction measures, especially with structural works.
                                                                                             Many federal environmental regulatory programs directly or indirectly
                                                                                      protect floodplain natural resources. These include programs established to
                                                                                      implement the Clean Water Act; the Safe Drinking Water Act; the Federal
                                                                                      Insecticide, Fungicide, and Rodenticide Act; the Solid Waste Disposal Act; the
                                                                                      Endangered Species Act; the Natural Historic Preservation Act; and others.
                                                                                             Statewide floodplain, wetland protection, or similar regulations may be
                   THE WILD AND SCENIC RIVERS ACT                                     applied directly by a state or, as is more often the case, by local communities
                   The Wild and Scenic Rivers Act of 1968 establishes                 according to state-established standards. Any alteration of the natural topog-
                   as national policy the protection of certain selected              raphy or habitat, or any damage to flora or fauna requires a permit in some
                   rivers (or segments of them) with particular natural               states. Cumulative impacts are considered during the permit review process
                   and cultural value. The National Park Service main-                in a few states, and mitigation of the loss of natural resources is often a con-
                   tains a list of rivers that are potential additions to             dition for permit issuance. Several states specifically protect wetlands with
                   the designated system. The Act prohibits the Federal               programs that outline minimal criteria for permit issuance and prohibit all
                   Energy Regulatory Commission from licensing any                    other development.
                   dam or other work on or directly affecting any river                      Local regulations, such as zoning and subdivision regulations, building
                   of the system and likewise prohibits otherfederal                  codes, housing codes, and sanitary and well codes, may directly or indirectly
                   agenciesfrom activities that would have a direct and               manage natural resources by including provisions for protecting habitat, water
                   adverse effect on the values incorporated into the Act.
                   Further, allfederal agencies are required, as part of              quality, and open space. Relevant provisions include setbacks from the shore,
                   their normal planning and environmental review                     limited density in coastal areas, restrictions or prohibitions on certain kinds
                   processes, to avoid or mitigate adverse effects on                 of development in such sensitive areas as barrier beaches and sand dunes, and
                   rivers being consideredfor wild and scenic                         specification of uses that will not degrade the natural resources of the site.
                   designation.

                                                                                         FEDERAL REGULATIONS AND THE NATURAL
                                                                                                  RESOURCES OF FLOODPLAINS
                                                      The Section 404 program under the Clean Water Act helps protect the natural resources of floodplains by regulat-
                                                    ing the discharge of dredged or fill material into waters of the United States, including adjacent wetlands. Permit appli-
                                                    cations are subject to a public interest review that includes consideration of floodplain values and flood hazards, and
                                                    compliance with the Environmental Protection Agency's section 404(b)(1) guidelines, which incorporate extensive
                                                    environmental criteria to prevent the loss of aquatic resources and minimize adverse environmental impacts. One
                                                    aspect of the guidelines provides for the mitigation of adverse impacts at one site by restoring alternative degraded
                                                    sites; it has been responsible for a number of experiments in rehabilitating degraded wetlands and creating new ones.
                                                      One of the most significant developments in protecting rare plant and animal species, many of which live in flood-
                                                    plain habitats, was the Endangered Species Act of 1973, which authorizes the designation of habitats critical to the
                                                    survival of threatened and endangered species. It directs federal agencies not to authorize, fund, or carry out actions
                                                    that mayjeopardize their existence or modify their habitats. Many states have developed their own programs of iden-
                                                    tifying and protecting rare and endangered species.
                                                    0 The National Historic Preservation Act of 1966 was passed, in part, because Congress recognized that federal projects,
                                                    such as highways, dams, and urban renewal, had damaged or destroyed thousands of historic properties during the
                                                    1950s and 1960s. The National Historic Preservation Program has operated as a working partnership between fed-
                                                    eral, state, and local governments, private citizens, the Advisory Council on Historic Preservation, and the National
                                                    Trust for Historic Preservation. The federal government provides guidelines, technical assistance, and grants in aid
                                                    for state and local historic preservation efforts, and monitors its own activities so that they do not unnecessarily harm
                                                    historic properties. State historic preservation officers coordinate the program, assist local governments and the pub-
                                                    lic and give them advice on preservation matters, and carry out other aspects of the national program on behalf of
                                                    the federal government. Preservation work at historic sites is done by localo governments, nonprofit organizations and
                                                    institutions, corporations, and individuals.

                 46

                                        Development and Redevelopment Policies
                           Important federal policies and programs affecting the design and location                                                     PROTECTION OF
                    of services and utilities in the nation's floodplains have been established in the                                        FLOODPLAINS AND WETLANDS
                    executive orders on floodplains and wetlands and in accord with the Wild and                                                    THROUGH REGULATION
                    Scenic Rivers Act and the Coastal Barrier Resources Act. The executive orders                                            Many Michigan communities have adopted com-
                    require federal agencies to evaluate their proposed actions in light of, among                                           binedfloodplain and wild and scenicriver regula-
                    other considerations, the proposed impact on the natural resources of flood-                                             tions to preserve the natural resources of these areas.
                    plains. Some states have executive orders to control placement of public facili-                                         0 Besidesfloodplain regulations that require permits
                    ties on floodplains, while others directly regulate these uses through statutes.                                         forfilling, grading, or construction, Virginia Beach,
                    A number of federal laws and programs provide funding and other assistance                                               Virginia, has adopted coastal wetland and sand dune
                    for acquiring and protecting floodplain land.                                                                            protection regulations that require building setbacks.
                           States protect natural and cultural resources with open space and rec-                                            0 A zoning ordinance in Clearwater, Florida,
                    reation programs that are occasionally linked to floodplain management.                                                  includes special regulationsfor environmental@ sen-
                    Most states have at least one program through which wetlands are brought                                                 sitive areas, including mangrove andfreshwater
                    into public ownership, although that usually was not its specific intent; fre-                                           swamps, barrier islands, coastal beaches, natural
                    quently wetlands are acquired because of their habitat, open space, or other                                             drainageways, and aquifer recharge areas.
                    value. Most states have now enacted legislation to protect wetlands; many of                                             0 In order to reduce bank erosion, increase ground-
                    these states have found that the incremental loss of small wetland areas still                                           water infiltration, and provide wildl2fe habitat, several
                    results in an unacceptable cumulative loss. In response, they are acting to                                              California communiti@s have adopted ordinances
                    tighten existing wetland protection programs. A related measure is mitigation                                            regulating the removal of riparian cover along
                    banking programs, which provide for the creation or enhancement of wet-                                                  watercourses.
                    lands at one site as compensation for damage that has or will occur to wet-                                              0 In Northampton, Massachusetts, 1,500 acres
                    lands as a result of development at another site. At least 10 mitigation banks                                           offloodolain along the Connecticut River have been
                    were functioning in the United States as of 1986. Mitigation banking is only                                             placed in an exclusive agricultural use district.
                    appropriate in certain situations and requires a great deal of administrative                                            * In East Hampton, New York, floodplain regula-
                    and planning effort, financial support, and commitment.                                                                  tions are supplemented by a beach grass protection
                           Several thousand communities have acquired a portion of their flood-                                              ordinance, tidal and inland wetland regulations, a
                    plains for parks, parkways, wildlife areas, conservation, agriculture, or other                                          dune setback regulation, and scenic easements to pro-
                    environmental or social uses. Some local jurisdictions have moved toward pro-                                            tect wetlands, dunes, and other areas.
                    grams to combine other community objectives with floodplain management,
                    including open space, hiking, cycling, water quality, aquifer protection, wetlands
                    protection, and the provision of fish and wildlife habitat. These multiobjective
                    programs typically take two forms: greenway or river corridor projects and
                    community redevelopment projects. The State and Local River Conservation
                    Assistance Program, administered by the National Park Service, is the prin-
                    cipal federal program for providing information, technical assistance, and
                    limited funding for such river planning.                                                                                              PROTECTION OF
                                                                                                                                              FLOODPLAINS AND WETLANDS
                                                                                                                                             THROUGH DEVELOPMENT POLICY

                                                                                                                                             0 A Glastonbury, Connecticut, floodplain regula-
                                                                                                                                             tion includes a density transfer mechanism un er
                                                                                                                                             which development rights may be shiftedfrom one
                                                                                                                                             place to another.
                                                                                                                                             & In the largest federally funded watershed
                                                                                                                                             management project in history, the U.S. Army
                                                                                                                                             Corps of Engineers purchased 8,500 acres of
                                                                                                                                             wetlands in the Charles River watershed up-
                                                                                                                                             stream from Boston, Massachusetts. These wet-
                                                                                                                                             lands provide 50, 000 acre-feet of flood water
                                                                                                                                             storage, eliminating the needfor a flood control
                                                                                                                                             dam or other structure and constituting significant
                                                                                                                                             areas of habitat and open space.
                                                                                                                7,
                                                                                                @7_                                           New Jersey used funds from the U.S. Fish
                                                                                                                                             a
                                                                                                                                             nd Wildlife Service's Federal Aid to Wildlife
                                                                                                                                   7-7       Fund to acquire additions to the 4,400-acre Cape
                                                                                                                   Ad-
                                                                                                                                              a Wetlands, which the state maintains as a
                                                                                                                                                             An adjacent 315-acre salt marsh
                                                                                                                                             wildlife refuge.
                                                                                                                                             was purchased,  and the owner of the property do-
                             Charles River naturalflood water storage area near Dedham, Massachusetts.                                       noted 25% of the land to the state, providing the
                                                                                                                                             state's required matchingfunds.
                                                                                                                                             Continued on next page

                                                                                                                                                                                                   77

                                PROTECTION OF
                     FLOODPLAINS AND WETLANDS
                   THROUGH DEVELOPMENT POLICY

                   Continuedfrom previous page
                      When the Wynoochee Dam was constructed in
                   Washington State, a portion of wildlife habitat                                                        T-7 7                                      A&
                   was lost under the lake and a number of elk and
                   deer were left homeless. To mitigate the loss, the
                   U.S. Army Corps of Engineers acquired 1, 034
                   acres of land to provide replacement winter                                        L
                   rangeland. Within each area, cultivated fields
                   supply winterforage, while the remaining area
                                                                                                                                                             _PF777@_"
                   serves as buffer and as habitat.                                    7"
                     Florida's Save our Rivers Program is one of
                   several that have protected substantial acreage for
                   habitat, water quality, watershed protection, and                   Floodplain managernent efforts have sometimes been unsuccessful because they are seen as benefitting only
                   recreation. Land has been purchased to restore                      sekct groups at the expense of an entire communiiy. Therefore, some jurisdictions have developed programs
                   channelized or impounded rivers thatfeed the                        that combine other communiy objectives-the development of open space and recreation facilities, or the protec-
                   Everglades, to restore the Kissimmee River to          its          tion of wetlands and water qualio, for example-with floodplain managernent.
                   original channels, to conduct a pilot project on                    Greenbelt park, Maryville, Tennessee.
                   marsh habitat renewal, and to preserve Parts of
                   the Green Swamp.                                                           The private sector, operating largely through private, nonprofit organi-
                   * The Mecklenberg Couno, North Carolina,                            zations, is heavily involved in acquiring land to protect it for open space and
                   Greenway Master Plan provides for the preserva-                     habitat, and much of that land is wetlands or floodplain land. As of 1989 the
                   tion offloodblains along more than 20 creeksfor                     Nature Conservancy was responsible for the protection of 3,643,352 acres in
                   passive recreation, habitat protection, and reduc-                  50 states, Canada, Latin America, and the Caribbean. The Audubon Society
                   tion offlood damages. A network of greenways is                     and Ducks Unlimited have active programs to help preserve wetlands.
                   planned that will include 4,000 acres and 60
                   miles of trails. As of 1986, over 1,000 acres                                                      Information and Education
                   had been acquired through donations, local park
                   bonds, and dedications.                                                    Information, education, and technical assistance are becoming more
                                                                                       important as natural resource managers and interest groups realize the benefits
                                                                                       of a public that is well-informed about natural systems and about the conse-
                                                                                       quences of decisions that affect them. Technical information and public edu-
                                                                                       cation about the natural and cultural resources of floodplains is provided by
                                                                                       the Environmental Protection Agency, the U.S. Fish and Wildlife Service, the
                                                                                       Office of Coastal Resources Management, and other federal agencies through
                                                                                       press releases, newsletters, magazines, and television programs. Most states
                                                                                       have active programs within their natural resources, environmental protection,
                                   PROTECTION OF                                       and parks and recreation departments that prepare and distribute literature,
                        FLOODPLAINS AND WETLANDS                                       films, and other materials. Many offer instructional courses to staff and offi-
                        THROUGH TAX ADJUSTMENTS                                        cials of local communities. Natural resource inventories and mapping are
                   At least 43 states offer real estate tax incentives to              major components of many state programs. Hundreds or thousands of private
                   leave land in agriculture, forestry, and certain other              organizations exist across the country to inform and educate the public about
                   open space uses; undevelopedfloodplains qualify                     natural resources, including those on floodplains. Environmental values are
                   under some of these statutes.                                       widely taught in schools at all levels, and popular television programs reach
                   0 A Florida program earmarks for the Water                          a wide audience. Research is an important predecessor to education and
                   Management Lands Trust Fund the revenues from                       technical assistance, and the information base on natural resources is being
                   a documentary tax of $.075 per $100. 00 on all real                 broadened continually.
                   estate transactions. The money is used to purchase                         Improved documentation and quantification (including dollar values)
                   and manage floodplains and wetlands. Revenues                       of the value of natural floodplains are needed to improve public understand-
                   over the next 30 years are expected to approach                     ing and acceptance of the need for protection. For example, few developers
                   $1 billion.                                                         seem to realize that floodplains and wetlands have great aesthetic appeal, that
                   *Minnesota's Tax Exemption and Credit Program                       in their natural state they can simultaneously enhance property values and
                   has two main components. Under thefirst, eligible                   continue to fulfill their normal natural and cultural functions.
                   wetlands are exemptfrom Propery taxes. Under the
                   second, landowners   .who agree not to drain wetlands                                                       Tax Adjustments
                   in a givenyear rece2ve a tax credit. Excess creditsfor
                   wetland propery may be applied to the landowner's                          Positive incentives for the preservation and restoration of floodplain
                   tax liabilityfor contiguous property. The state reim-               resources can be provided through several kinds of tax adjustments, although
                   burses countiesJor revenues lost due to the exemptions              this technique has not been widely used. Federal income and estate tax bene-
                   andfor the value of the tax credits.                                fits, which are available to individuals and organizations who donate land and
                                                                                       provide easements to governments and eligible nonprofit organizations, have
                48

               been a major factor in facilitating private donations of property with valuable
               wildlife and habitat functions or historical significance. Most conservation
               organizations are tax exempt, and many of them are active in protecting the
               natural and cultural resources of wetlands. Almost all states offer tax incen-
               tives for open space uses.

                                        Administrative Measures
                    Many different administrative measures can be used specifically to pre-
               serve and restore the natural and cultural resources of floodplains, including
               restrictions or conditions on contracts, grants, loans, permits, and licenses;
               encumbrances during land conveyance; delegation of responsibility for flood-
               plain activities to a specific authority; comprehensive planning; systematic
               review of agency programs to identify opportunities for preservation and res-
               toration; and coordination among federal, state, local, and private agencies to
               implement unified efforts. Some of the most important administrative meas-
               ures address the inventory, classification, and mapping of wetlands, wildlife,
               aquifers, and other natural resources. It is necessary to know what natural
               resources exist in the floodplain and what their individual and collective value
               is before making land use decisions that will sustain those values and functions.
                    Planning historically has been used by governments for many kinds of
               activities besides natural resources management. Comprehensive planning
               provides an opportunity for taking a holistic view of floodplain resources
               while also meeting other local needs, such as water supply, agricultural ero-
               sion control, recreation, and economic development. This sort of planning is
               getting increasing attention at the state and local level, and typically incor-
               porates several of the tools discussed above.

                                                  Multiple Use Planning for a Floodplain

                          PART III

                   THE'EFFECTIVENESS OF
                  FLOOPPLAIN MANAGEMENT

                                                         1" or
                                               "'vow

                                                                  X.

                                                                                                                  Perception and Awareness
                                                                                                                         of Floodplain Losses

                                                                                          Both individual and institutional perception and awareness of flood risk and
                                                                                          vulnerability affect floodplain management. Although substantial progress has
                                                                                          been made in increasing institutional awareness and response, individual per-
                                                                                          ception and awareness generally falls far short of what is needed. This short-
                                                                                          fall makes itself unpleasantly felt in the unwise development of flood hazard
                                                                                          areas and in disregard for the value of natural floodplains,

                                                                                                                                 Recognition of Risk
                                                                                                 Local perception of flood hazards-by both governments and floodplain
                                                                                          residents-is related to previous experience with flooding; the extent to which
                                                                                          the floodplain is developed; the existence of structural control measures; the
                                                                                          seriousness of the flooding in relation to other community problems; and atti-
                                                                                          tudes about land use, water resources management, and regulations. In general,
                                                                                          the threat of damage from coastal flooding seems to be taken more seriously

                          FLOODPLAIN MANAGEMENT
                                    TERMINOLOGY

                   Some misperceptions aboutfloodplain management
                   are the result of simple lack of understanding. For
                   example, probably the most misunderstood concept is
                   the "100-yearflood.- The term is often talxn liter-
                   ally, causing individuals to believe, incorrecto, that
                   if they or their community have experienced a 100-                                                                                           -INN"
                   yearflood, a similar one cannot occurfor another
                   century. The terms '7% annual chance flood" and
                   "national baseflood standard" have been suggested                                                                                                                  jq@
                   as less-misleading substitutes.
                   Use of the term 'floodproofing" also can give a
                                                                                             e4s
                   false sense of securiy about susceptibility to flood
                   damage. The techniques involved in floodproofing d9                                                                                  7
                   not make a structure comptete!@ safe from flooding.
                   The term 'flood-resistant construction" has been
                   suggested as an alternative.                                           Although public knowledge concerningflood risks has  increased significantly in the last 30years, development
                                                                                          in hazar6gusareas is still occurring.
                                                                                          Flooding and alluvial fan, Magnolia Spring Canyon, Rancho Mirage, California, July 1979.

                                                                                          by communities than is damage from riverine flooding. Because most people
                                  REGULATION AND                                          discount the probability of loss from infrequently occurring events, such as
                                PUBLIC AWARENESS                                          large floods, individual and community experience with flooding results in
                   Many regulatory measures have been instituted by                       both heightened perception of risk and increased attention to solving flood
                   governments in an effort toforce individual aware-                     problems. The perceived seriousness of the flood problem is directly asso-
                   ness offlood hazards and protective action. For                        ciated with the extent of floodplain development and existence of intensive
                   example, the National Flood Insurance Program is                       land uses in the hazardous area; increasing development may result in greater
                   voluntary, but changes have been made in the law                       awareness of flood problems. The presence of structural flood control measures
                   since it was passed in 1968 in order to encourage                      has varying effects on perception of risk and subsequent responses; structural
                   greater participation. Primary among these was the                     measures may contribute to a sense of complacency, as though the problem
                   Flood Disaster Protection Act of 1973, which pro-                      were "solved."
                   hibits nonparticipating floodprone communitiesfrom
                   receiving disaster assistance after aflood. Another                           Private citizen perception of risk may be quite different from that of local
                   mechanism intended to promote awareness and com-                       officials. Even if the risk is acknowledged, the advantages of a floodplain loca-
                   phance is the provision thatfederally insured banks                    tion to the individual property owner may seem to outweigh the disadvantages.
                   and otherfinancial institutions require purchasers of                  Homeowners also may be more concerned with the effect of floodplain regula-
                   homes and other structures in thefloodplain to take                    tions on resale value than with the effect of a potential flood on the house or
                   outflood insurance. This procedure has not been                        property itself Some studies have found that even after a control structure is
                   wholly effective because the institutions currento are                 built, local governments remain concerned about a flood problem, while the
                   not penalized tf theyfail to comply.                                   citizens themselves tend to forget about the threat. Both individual and com-
                                                                                          munity perception of risk may be tempered by other considerations, such as
                                                                                          apprehension about the potential secondary effects of land use management-
                Precious page.. Charks River watershed, Massachusetts.                    reduction in property values, slowed economic growth and development,
                                                                                  I       reduction in the tax base, and increased construction costs.
                 52

                    Informing and educating the public about both flood risk and about the
               importance of the natural and cultural resources of floodplains is an ongoing
               effort. Much research has examined ways to provide information and to make
               people take action, and new techniques are being sought continually. Typical
               means of providing information to the public include distribution of pam-
               phlets and other publications; use of radio, television, and newspapers; place-
               ment of warning signs; and many other more imaginative methods. A few
               jurisdictions require real estate agents to provide flood and other hazard
               information to prospective buyers of homes.

                            Awareness of the Value of Natural Floodplains
                    The protection of the natural and cultural resources of floodplains is
               beginning to emerge as a popularly expressed environmental objective; it is
               already encompassed in the broader environmental goals embraced through-                   PUBLIC SUPPORT FOR WETLANDS
               out the nation. The general level of public environmental awareness and sup-              Concern for the Ivss of wetlands and supportfor their
               port for all types of protection programs has increased dramatically in the               protection appear to be increasing. A 1982 Harris
               past 25 years, and the importance of preserving wetlands, protecting endan-               pollfound that 8317o of respondentsfelt that it is
               gered species, and maintaining water quality is widely recognized.                        "very important" to preserve the nation's remaining
                    This kind of awareness represents a potentially broad base of public sup-            wellands. A 1985 poll reaffirmed this broad sup-
               port for floodplain management. Unfortunately, this voiced support does not               port: 85 To of those polledfavored strict enforcement
               necessarily translate into action, particularly when an individual's own prop-            of the Clean Water Act and its wetlands protection
               erty is involved. Any restriction on individual property rights may be strongly           requirements.
               resisted, or the loss of natural values may seem inconsequential because of the
               small area affected.

                                        Protecting the Environment

                    Percentage of the U.S. population that agreed with the following
                    statement:

                               Protecting the environment is so important that
                    90       requirements and standards cannot be too high and
                  '00@ continued environmental improvements must be made
                    80                         regardless of cost.

                    70

                    60-

               a)
               L)
                    50-

                    40-

                    30-

                    20-

                    10-

                      0
                                 1981                   1984                   1986
                                                        Year

                                                                                                                                                 73

                    METEOROLOGICAL DATA: THE NWS                                               Knowledge, Standards, and Technology
                    The collection and analysis of weather data for                     Effective floodplain management requires a sound understanding of the
                    floodplain management-precipitation intensity,                      physical, biological, and chemical processes that affect flood hazards and
                    extent, and duration; wind data; and temperature-                   the natural resources of floodplains, as well as an appreciation of the social
                    is the responsibi&y of the National Weather Servi@e.                processes involved in human interaction with them. The last 25 years have
                    The NWSs d2ta collection system extends through-                    witnessed a rapid expansion of the knowledge, information base, and techno-
                    out the 50 states, offshore, and across the Pacific                 logical expertise in floodplain management-products of the combined efforts
                    Ocean, and now consists of about 230 staffed stations,              of governments at all levels, academic institutions, and the private sector.
                    165 automated stations, and almost 400 stations
                    under contract. In marine locations, automated
                    moored and drifting data buoys are used A network                                       Climate Change and Weather Forecasting
                    of automatic hydrological observing system stations is                    One of the basic assumptions of hydrology and floodplain management
                    operated to provide near real-time data of river stages             has been that long-term climate is constant. Over the past few decades, how-
                    and rainfall. The NWS also operates 128 weather                     ever, new evidence has suggested that climatic changes can take place rather
                    radar stations that provide information an areal                    quickly (over a decade or so) and last for half a century or more. Therefore,
                    coverage, height, intensity, and rnovement of storms                the traditional 30-year averages of various climatic parameters- precipitation,
                    for warning andforecasting and hydrological and                     for example-that have been the basis of past policy may be misleading for
                    climatological programs. Over 1,300 ships report
                    data systematically, and 300 others report d2ta                     decisions involving long-term consequences.
                    whenever they are in waters covered by NWSjore-                           During the 1970s and 1980s, indications of a global warming trend
                    casts.                                                              increased, and some scientists hypothesized that human use of fossil fuels was
                                                                                        amplifying the greenhouse effect sufficiently to cause changes in global climate.
                                                                                        The normal historical relative rise in sea level is expected to continue over the
                                                                                        next century, and as a result of the human-induced climate changes, the rate
                                                                                        of rise is anticipated to increase. The predicted rise in global mean sea level
                                                                                        is about 20 cm by 2030, and 65 cm by the end of the next century, with sig-
                                                                                        nificant regional variations. This could have profound flooding implications.

                                                                                                                                Streamflow Data
                                                                                             Over 90% of the 7,492 daily-record stream gages in the United States
                                                                                        are operated by the U.S. Geological Survey in cooperation with a local spon-
                                                                                        sor. Since the first stream gage was established in 1889, the U.S. Geological
                                                                                        Survey network expanded until 1980, but has declined since then, largely due
                                                                                        to reductions in funding by local cooperators. This makes spatial and tem-
                                                                                        poral consistency in gathering these data difficult. Even though information
                                                                                        about runoff from small watersheds (between one and two square miles) is
                                                                                        important for many purposes, including highway drainage design and urban
                                                                                        drainage analysis, almost all of the nation's stream gages are located on larger
                                                                                        watersheds. To partially fill this gap, the Agricultural Research Service has
                                                                                        gaged hundreds of plot-sized watersheds to measure runoff for individual land
                                                                                        uses and soils.

                      HYDROLOGICAL DATA: THE USGS                                                                       Hydrology and Hydraulics
                                     AND THE EPA                                              Hydrologic parameters of importance to floodplain management are
                    Water data have been published annual@y by the                      flood peak flows; flood volumes; time of concentration and travel; rate of rise;
                    US. Geological Survey since 1890. Records are                       water velocities; sedimentation and degradation of flood channels and flood-
                    now published annual@jbr each state and main-                       plains; flood elevations; the effect of geomorphology on floods and vice versa;
                    tained on a computerized data base, the National                    the hydraulics of flood channels, floodplains, and human-made structures;
                    Water Data Storage and Retrieval System. It                         and water quality as affected by floods. These characteristics and their inter-
                    includes data from USGS surface water records,                      relationships are generally modeled mathematically.
                    with an indexfor the 320,000 water data storage                           Inexpensive, easy-to-use computers have made it possible to apply
                    sites; over 240 million dai@ parameters such as                     accepted methods of hydrology and hydraulics analysis to many floodplain
                    streamflow, groundwater levels, specjti'c conductance,
                    and water temperatures; 460,000 records of annual                   management activities. The susceptibility to flooding of small developments
                    maximum streanfow and gage height values; 2.3                       and even single structures now can be evaluated relatively quickly and inex-
                    million analytical results describing biological, chem-             pensively. Researchers and a few practitioners are using two- and three-
                    ical, and physical water characteristics,- and construc-            dimensional analyses of flood flows to obtain more realistic and reliable results
                    tion history, geohydrologk data, and one-timefield                  than those yielded by the step-backwater analysis. Several models and methods
                    measurements on 850, 000 sites. The Environmental                   are available for mapping the 100-year flood in coastal areas, for determining
                    Protection Agency has a water quality data base of                  stillwater flood elevation from hurricanes along the Atlantic and Gulf coasts,
                    nationwide information on water qualiy, water                       and for accounting for the effects of wave heights, wave runup, and marsh
                    qualio standard@, point-source pollution, fish kills,               grass. Other models address flooding on the Great Lakes, flooding from
                    waste abatement needs, and other topics.                            tsunamis, and other special situations. Sediment transport models are being
                 54                                                             1       developed, calibrated, and applied in many areas. All these techniques, which

                                                                   A                                                                                               COMPUTER MODELS FOR
                                                                                                                                                              HYDROLOGY AND HYDRAULICS
                                                                                                                                                         Computer programs like the Soil Conservation Serv-
                                                                                                                                                         ice's TR-20 and the US. Arny Corps of Engi-
                                                                                                                                                         neers' HEC-I can be used to mathematically model
                                                                                                                                                         hydrologic conditions based on such parameters as
                                                                                                                                                         flood peaks, volumes, rate of rise, and velocity.
                                                                                                                                                         Other programs in use today are the Soil Conserva
                    A
                                                                                                                                                         tion Service's TR-55for small urban drainages and
                                                                                                                                                         the Environmental Protection Agency's SWAIMfor
                                                                                                                                                         urban drainages where water qualio is important.
                                                                                                                                                         To determine a water-surlace elevation for a single
                                                                                                                                                         point on a stream, the Manning equation is often
                                                                                                                                                         used and can give good results where normalflow
                                                                                                                                                         prevails and there are no downstream obstructions.
                                                                                                                                                         However, when there are obstructions or other special
                    In recentyears, microcomputers have    made it possiblefor agencies  andjurisdu@ons at     all levels to use                         conditions, a backwater analysis is used, and com-
                    sophisticated hydrologic and hydraulic models to analyze potential flooding at virtualo   any scale.                                 puter models have been developed to perform it as
                    Microcomputer workstation at the Floodolain Management Section, Louisiana Department of Transportation                               well. The most widely used backwater model is the
                    and Development.                                                                                                                     Corps'HEC-2. A special dynamic routing model
                                                                                                                                                         has been developed by the National Weather Service
                    only a decade ago were very expensive and hence infrequently applied, help                                                           forflood routing and inundation from dam breaks.
                    evaluate the effects of future urbanization, structures, and other land use                                                          The NWS also developed thefirst widely applied
                    changes. Although the computer revolution has improved many aspects of                                                               model, known as SPLASH, for early mapping of
                    flood hydrology and hydraulics, it has also made possible misuse of the stan-                                                        coastalflood zones under the National Flood Insur-
                    dardized techniques by those not fully aware of the assumptions and limits                                                           ance Program. A more sophisticated model, SLOSH
                    inherent in the methods.                                                                                                             (Sea, Lake, and Overland Surgefrom Hurricanes),
                                                                                                                                                         was developed in 1975 to modelflood levels at the
                                                   Flood Forecasting and Warning                                                                         coastlinefor hurricanes of a particular magnitude,
                                                                                                                                                         forward speed, and track. Today, the Coastal
                           Weather forecasting, and hence flood forecasting, is improving with                                                           Flooding Hurricane Storm Surge Model is used
                    remote sensing capabilities and the availability of more real-time data. New                                                         by the Federal Emergency Management Agency to
                    radar equipment, such as NEXRAD, and other tools promise better precipi-                                                             analyze coastalflood hazards.
                    tation forecasts for small-scale storms and flood forecasting for small water-
                    sheds. The combination of new satellite data on snow pack and real-time data
                    on precipitation and temperatures may be combined with established runoff
                    models and recurrence interval techniques to produce seasonal flood forecasts.
                           There are a small number of automated flash flood warning systems
                    throughout the country, notably in Arizona, California, Colorado, Connecti-
                    cut, Maryland, Nevada, New York, Pennsylvania, and Texas. The performance                                                            kN1
                    of these systems has been uneven; most have not been tested under actual
                    flooding situations to determine if they will indeed provide the anticipated
                    level of warning. As the technology improves and operation and maintenance
                    experience is gained, additional automated systems will come into use, signifi-
                    cantly reducing the loss of life from flash floods.

                                                  Soil Identification and Mapping
                           Soil maps and data have proven useful in identifying and classifying
                    floodplains and wetlands. The modem soil survey, with improved techniques
                    and standards, began in the mid-1950s. By 1983, the Soil Conservation Service
                    had mapped and classified about two-thirds of the U.S. land area (except
                    Alaska), or nearly 1.3 billion acres. The Soil Conservation Service expects to
                    complete soil surveys for the entire country by 2000. The agency is beginning                                                                                            4            .4
                    to digitize existing soil surveys, and most of the remaining soil survey maps                                                                  A.
                    may be prepared with digital methods at the outset. This should improve the
                    level of detail of soil classifications, standardize the map scales, and provide
                                                                                                                                                          V
                    additional supporting information.                                                                                                          I
                                                                                                                                                                                                           ?A1_11      My
                                                                                                                                                                                                                       A"

                                                                                                                                                         Warning siren  tied toflood sensors, Lavaca   River,  near
                                                                                                                                                         Hallettsville, Texas.

                                                                                                                                                                                                                       75

                                                                                                              Mapping Flood Hazards
                                                                                     Nationwide mapping of floodprone areas may well be the single great-
                                                                               est achievement in floodplain management to date. Before enactment of the
                                                                               National Flood Insurance Act, floodplain mapping was done through the
                                                                               programs of the Corps, the Sod Conservation Service, the U.S. Geological
                                                                               Survey, and the Tennessee Valley Authority. Each agency mapped floodplains
                                                                               according to its individual authority and primary mission, and often on a
                                                                               project-by-project basis or only after major floods. The Corps compiled a
                                                                               national list of incorporated communities with flood problems and in 1962
                                                                               began mapping and providing the information to individual communities in
                                                                               floodplain information reports. Mapping of floodplains for the National Flood
                       THE COST OF FLOOD MAPS                                  Insurance Program began in 1968, when the Federal Insurance Administra-
                 The Federal Insurance Administration now spends               tion began producing temporary maps to show approximate boundaries of
                 about $36 million annually to keep publishedflood             floodprone areas in identified communities and entered into cooperative
                 risk information updated and current and to provide           efforts with other federal agencies and contracts with private engineering
                 detailedflood risk data where none existed before.            firms to develop methods for preparing more detailed maps. By 1990 more
                 Of this amount, about $4 million annually is spent            than 12,000 new flood insurance map studies had been initiated and over
                 to distribute about seven million maps to states,             1,700 restudies undertaken at a cost of nearly $900 million. In addition to
                 communities, lenders, agents, banks, consultants,             contracting with numerous private firms, the Federal Insurance Administra-
                 and others.                                                   tion used the resources of the Corps, the U.S. Geological Survey, the Soil
                                                                               Conservation Service, the Tennessee Valley Authority, the Bureau of Reclama-
                                                                               tion, the National Oceanic and Atmospheric Administration, the Delaware
                                                                               River Basin Commission and the Susquehanna River Basin Commission, and
                                                                               some states to perform this work.
                                                                                     Twenty-three states fund and prepare their own floodplain maps to com-
                                                                               plement the National Flood Insurance Program-to provide greater detail or
                                                                               a better scale, to reflect changes in development or hydrology, to extend map-
                                                                               ping beyond corporate limits, to meet special requirements, or to cover special
                                                                               natural values. In the past few years, communities themselves have become
                                                                               more involved in mapping, either because of unique floodplain problems
                                                                               or because comprehensive local programs require more specialized mapping.
                                                                               In addition, private consultants frequently perform hydrological or drainage
                                                                               studies for subdivisions and other developments. These studies form the basis
                                                                               for many amendments and revisions to original flood insurance maps.

                                                                                                                        MV Sr                                               WA),
                                                                                                                                 t                           AY
                                                                                                                                                                a,-
                                                                                                                    Cn 0       *1                          CCW,400ft

                                                                                                                         52

                                                                                                          0

                                                                               The foundation of the Nationd Flood Insurance Program is accurate maps of hazard areas in j7oodprone
                                                                               communities. The program has been producing such maps since its inception in 1968
                                                                               Flood Boundary and Floodway Map of the Fishkill, New York, area.

               56

                                Understanding and Mapping Wetlands
                     Since the 1970s significant progress has been made in both scientific and
                public awareness of the value of wetlands. In 1986 the Environmental Protec-
                tion Agency adopted a plan of research on ways to create, restore, and enhance
                wetlands and their functions. National wetlands mapping is being performed
                by the U.S. Fish and Wildlife Service. The detailed (scale 1:24,000) wetland
                maps are used by local, state, and federal agencies and private organizations
                for many purposes, including comprehensive resource management plans,
                environmental impact assessments, pen-nit reviews, facility and corridor siting,
                oil and chemical spill contingency plans, natural resource inventories, and wild-
                life surveys. They show the location, shape, and characteristics of wetlands
                and deepwater habitats on a U.S. Geological Survey base. Wetlands are clas-
                sified according to the Fish and Wildlife Service's wetland classification system.
                Maps have been done for 6517c of the lower 48 states and 20% of Alaska. In
                addition, many states have developed their own wetlands mapping programs.

                            Understanding Natural and Cultural Resources
                     As discussed in Part II, the nation's floodplains contain some of its
                most important natural and cultural resources. A wide variety of data sources
                now provides information about these national assets. For example, the U.S.
                Environmental Protection Agency maintains several dozen water-quality-
                related data bases, and the U.S. Geological Survey compiles extensive natural
                resources data through its Water Data Storage and Retrieval System and the
                National Water Data Exchange. Additionally, the U.S. Fish and Wildlife
                Service, as part of its National Wetlands Inventory, is developing a computer-
                ized multidimensional wetlands mapping scheme for the entire country. The
                U.S. National Park Service has established the Nationwide Rivers Inventory
                of more than 1,500 river segments and maintains much other data on both
                natural and cultural resources. NOAA's National Ocean Service and National
                Marine and Fisheries Service maintain natural resources data in several data
                bases as part of NOAA's responsibilities as the nation's principal marine
                science agency. The Soil Conservation Service oversees the National
                Resources Inventory-a survey of land use and quality, based on 160-acre
                units across the United States-and the U.S. Forest Service similarly keeps
                extensive information on lands within the national forest system.
                     Beyond these federal resources, state agencies, private organizations, and
                universities also maintain comprehensive data describing many aspects of the
                nation's cultural and natural resources.

                                        Remote Sensing Techniques
                     In the past 20 years the availability and analysis of high-altitude pho-
                tography, satellite imagery, and other forms of remote sensing have increased
                tremendously. Systematic comparison of images from different times yields
                information on changes in land use, which can be used to help assess many
                natural resources and identify areas where future flood damages may occur.
                After the land uses and natural resources of an area are calibrated, most of
                the subsequent analysis can be automated. So far these techniques have had
                limited application in relatively small areas of the nation's floodplains, but
                technological advances in computer capabilities and data management systems                      HENDERSON COUNTY'S GIS
                should accelerate the use of remotely sensed data in the near future.                      The Henderson County, North Carolina Soil and
                     At least one Arizona community uses periodic aerial observations to look              Water Conservation District is one of thefirst in the
                for floodplain violations. Aerial photography combined with floodplain maps                nation to install a microcomputer-based geogrqphi@
                has been used in some communities to count the number of structures within                 in
                                                                                                            f@rmation system to provide better interpretative
                selected floodplains. Other communities have used or plan to use low-level                 soils information. The county's published soil survey
                aerial photography after floods to help determine the extent of flooding and               has been digitized and stored in the system, and the
                damage. As digital mapping becomes more widespread, it will become easier                  computer can capture, store, ana0ze, and retrieve
                and more inexpensive to monitor floodplain activities through remote sensing.              soils maps and other geographic d2ta. Fundingfor
                                                                                                           the &-monstration project was provi&d by the Ten-
                                                                                                           nessee Valley Authority, supplemented hy the Soil
                                     Geographic Information Systems                                        Conservation Service and the Henderson County
                     Many organizations now make routine use of geographic information                     Commissioners.
                systems (GIS)-computer systems that allow users to collect, manage, and
                analyze large volumes of spatially referenced and associated attribute data-                                                         57

                                                                                           for a wide variety of purposes, including natural hazards and natural resource
                                                                                           management. GIS-generated maps are easily manipulated and can be up-
                                                                                           dated at a low cost. However, GISs have not yet become widely used, mostly
                                                                                           because the initial cost of digitizing the needed information for input into a
                                                                                           GIS system can be formidable. Another handicap is that the different systems
                                                                                           now in use are not always compatible. Once these obstacles are overcome,
                                                                                           GIS technology will allow planners and managers to more easily obtain and
                                                                                           apply the information they need to make wise decisions about floodplains.
                                                                                           The Federal Emergency Management Agency is developing a standard for
                                                                                           digital flood insurance maps in public domain format and has committed to a
                                                                                           program to digitize the maps for over 340 metropolitan counties with large
                                                                                           amounts of property at risk from flooding.

                                                                                                                      Regulatory and Design Standards
                                                                                                 Over the past 20 years numerous standards of terminology, procedure,
                                                                                           performance, and quality have been developed in floodplain management.
                                                                                           They include both prescriptive standards (clear-y identified limits set by law,
                                                                                           policy, or custom), and performance standards (requirements that a specified
                                                                                           goal be reached by unspecified means). Some of these standards are freely
                                                                                           adopted, others are met in response to an incentive, and still others are required
                                                                                           by law. Many manuals and technical reference volumes have been developed
                                                                                           to assist builders and regulators to meet the performance standards required
                                                                                           by the National Flood Insurance Program. Having these standards has
                                                                                           provided a uniform means of applying, reviewing, and evaluating the design,
                                                                                           construction, and regulation carried out in support of floodplain management.
                                                                                                 Not all aspects of floodplain management are amenable to nationwide
                                                                                           standardization. There have been no national standards established for mini-
                                                                                           mum setbacks from river channels, although there are some statewide stan-
                                                                                           dards for designated streams, lakes, and other water bodies. Lincoln Township,
                                                                                           Michigan, for example, requires setbacks of 110 feet from dune and bluff areas
                                                                                           on Lake Michigan, while Wisconsin requires a minimum setback of 75 feet
                                                                                           from the ordinary high-water mark. There are no national standards for dam
                                                                                           and reservoir construction; instead, each federal agency has its own set of
                                                                                           criteria. Likewise, each of the three agencies (the Corps, the Soil Conservation
                                                                                           Service, and the Bureau of Reclamation) that constructs federally funded
                                                                                           levees has its own policies for construction and maintenance.

                                                                                           judicial Support for Floodplain Management
                          AVOIDING CONSTITUTIONAL                                          Over the last few decades the types of lawsuits and the specific issues liti-
                       CHALLENGES TO REGULATIONS                                           gated in floodplain management have changed, reflecting the predominant
                   To reduce the chances of having theirfloodplain                         techniques of the time and general status of the relevant law. Before 1968,
                   management regulations found unconstitutional,                          most litigation challenged the power of governments to undertake flood control
                   many jurisdictions have                                                 measures and to regulate floodprone lands. From 1968 to 1978 concepts of legal
                       0 adopted regulations with stringent performance                    liability expanded and government defenses to it diminished. Constitutional
                       standards rather than simpo prohibiting all                         challenges to regulations increased and shifted from broad constitutional
                       activities in hazard areas;                                         attacks to specific challenges to the reasonableness of particular measures.
                       * mappedfloodplains in more detail and more                         Since then, courts have continued to hold governments liable for their actions
                       accurateo than has the National Flood Insurance                     that increase flood damages. The number of constitutional challenges to
                       Program;                                                            regulations has diminished, however, due to the widespread judicial support
                       9 provided real estate tax breaks for tightly con-                  for regulations over the previous 20 years. Most recent cases have addressed
                       trolled land to diminish thefinancial burden of                     relatively technical issues, such as the validity of nonconforming use provi-
                       owners whose use of their property is greatly                       sions and setbacks.
                       restricted;
                         improved their permitting and record-keeping                                                   Constitutionality of Regulations
                       procedures to include detailed statements offind-                          Floodplain management regulations have been challenged as unconstitu-
                       ings on denials in order to provide a better                        tional on two fronts: as violations of due process guarantees and as takings of
                       defense in court.                                                   private property. The due process claims, which were based on a general legal
                                                                                           argument that the federal, state, and local governments had no legal authority
                                                                                           to regulate activities on floodplain lands and waters, have almost disappeared
                                                                                           over the years as the statutory authority to regulate was clarified and strength-
                58                                                                         ened. With the exception of a few cases in which regulations prevented all

                   economic use of floodplain property, courts likewise have upheld the general
                   validity of floodplain regulations against claims that they take private property                                             AVOIDING LIABILITY FOR FLOOD
                   for public use without payment of just compensation, in violation of the Fifth                                                                 DAMAGES
                   Amendment to the U.S. Constitution. These rulings are consistent with a                                                   There are many actions that state and local govern-
                   much larger body of law in which courts have upheld other land use regula-                                                ments can take to reduce their potential liability for
                   tions against claims of taking, despite the impact of the regulation upon prop-                                          flood damages:
                   erty values. Floodplain management regulations have been supported for a                                                        Obtaining legal advice before taking anticipated
                   number of reasons.
                                                                                                                                                 actions,-
                         0  The rights of private landowners to their water-oriented lands are                                                   * adopting comprehensive flood hazard plans,
                            subject to public trust and navigable servitude rights and interests.                                                because they can avoid liability if they avoid
                         0  Courts give great weight to protection of public health and safety                                                   flood h=rds;
                            and have, without exception, sustained regulations needed to prevent                                                 0 enrolling in the National Flood Insurance Pro-
                            nuisances (such as blockage of flood flows) and to prevent private                                                   gram, because landowners are less like@ to sue
                            actions that may threaten public or private safety on other property                                                 for damages if they are insured and thus quickly
                            (such as construction of dams).                                                                                      receive compensationfor their losses;
                         0  Over the past 20 years courts have upheld performance standards such                                                 * adopting drainage as well asj7ood hazard
                            as the requirements that private landowners protect the floodway's con-                                              reduction plans and regulations (most suits against
                            veyance capacity and elevate or otherwise protect structures to the 100-                                             cities Jorflood problems are really for damages
                            year flood elevation.                                                                                                due to interference with natural drainage),-
                         0  Courts have supported technically based regulations adopted consistent                                               * operatingflood loss reduction measures
                            with a federal, state, or local overall plan and standards (pollution con-                                           (structures, warning systems) with greater care
                            trols or the National Flood Insurance Program, for example).                                                         to avoid claims of negligence;
                                                                                                                                                 6 avoiding hazardbrone locations for public
                                                  Liability for Flood Damages                                                                    facilities;
                         In contrast with the small number of successful constitutional challenges                                               * designing public works-roads, sewers,
                                                                                                                                                 bridges, and water treatment facilities-to com-
                   to governmental floodplain management actions over the last 20 years, land-                                                   p@y with federal, state, and localfloodplain
                   owners have won thousands of damage suits against governmental units for                                                      guidelines and regulations so they d9 not block
                   causing or increasing flood damages. Most of these have been based on such                                                    floodflows or cause drainage problems;
                   common law grounds as nuisance or trespass.                                                                                   * Undertaking remedialflood loss reduction
                         There have been more successful liability suits in recent years because                                                 measuresfor existingfloodprone development,
                         �  Large damage awards from juries (and subsequent payments of them                                                     particularly where the problem has been parto
                            by governments with "deep pockets") have made plaintiffs and lawyers                                                 the result ofgovernment action,-
                            more willing to litigate;                                                                                            *purchasing liability insurance and establishing
                         �  Courts have recognized broadened concepts of public and private land-                                                seo' insurance pools.
                            owner responsibility to other landowners and the public;
                         � The "act of God" defense has diminished as a result of improved flood
                            prediction capability and maps;
                         �  Improved data on stream flow and better hazard modeling have made
                            proof of causation of the damages easier;
                         �  Improved technology, wider use of that technology, and adoption of
                            regulations and guidelines have all raised the standard of "reasonable"
                            actions on the part of government; and
                         �  The "sovereign immunity" defense of states and local governments,
                            and to a lesser extent the federal government, has been modified by
                            statutes and case law, making the governments responsible for more
                            actions and their consequences.

                                                     Avoiding Legal Problems
                         There is little doubt that perform ance-oriented floodplain regulations
                   (building codes, subdivision regulations, zoning, etc.) will continue to be
                   upheld in the courts despite restrictions that may affect private property
                   owners in some instances. Likewise, carefully crafted flood loss reduction
                   measures will reduce community and state liability in the long run. It is
                   important, however, that governments take care when formulating and
                   implementing these measures to reduce potential legal problems and lessen
                   the risk of constitutional challenge.

                                                                                                                                                                                                      79

                                                                                                              The Present and the Future

                                                                                                                                      Overview
                                                                                        It is difficult to assess the effectiveness of floodplain management in the
                                                                                        United States. The degree of accomlishment to date is impressive; at the same
                                                                                        time, a considerable distance remains between the status quo and the ideal that
                                                                                        can be envisioned. Two principal complications are that there are few clearly
                                                                                        stated, measurable goals, and that there is not enough consistent, reliable
                                                                                        data about program activities and their impacts to tell how much progress
                                                                                        is being made in a given direction.

                                                                                        Overall Effectiveness
                                                                                               There is general agreement on three fronts:
                                                                                               0 Floodplain management should reduce the number of flood-related
                                                                                                 deaths in the nation. This goal has been partially achieved. Average
                      Between 1916 and 1985, there were an average of                            annual loss of life from flooding has been somewhat reduced from the
                      about 100flood- related deaths annually,- there is no                      level that prevailed early in this century and has remained relatively
                      indication that deaths are increasing or decreasing on                     constant for many years.
                      a per capita basis.                                                      0 Floodplain management should result in an actual decline in the
                                                                                                 nation's flood losses, including public and private property damage,
                                                                                                 injuries, and disaster relief. This has not been achieved. In fact, there
                      Per capita flood damages were alinost 2.5 times as                         was a definite increase in flood damages from 1916 to 1985, although
                      greatfrom 1951 to 1985 as they wereftom 1916                               there is evidence that these losses have remained fairly constant over
                      through 1950, after adjustingfor inj7ation.                                the last two decades when compared to broad economic indicators like
                                                                                                 the GNP.
                                                                                               * Floodplain management should reduce the loss of the natural and cul-
                                                                                                 tural resources of the nation's floodplains. The programs designed to
                      The natural and cultural resources offloodplains are                       do this have not yet arrested that deterioration.
                      being lost at unacceptable rates.
                                                                                        Achievements to Date
                                                                                               Several significant achievements in floodplain management can be noted,
                                                                                        even though all the goals have not yet been reached.
                                                                                               � There is now more widespread public recognition of flood hazards, the
                                                                                                 value of the cultural and natural resources of floodplains, and the close
                                                                                                 interrelationship of the hazards and the resources.
                                                                                               � There is an extensive body ofjudicial decisions supporting floodplain
                                                                                                 management activities, indicating a perception throughout society that
                                                                                                 floodplain losses can and should be managed.
                                                                                               � Numerous standards of terminology, procedures, performance, and
                                                                                                 quality have been developed, providing a uniform means of applying,
                                                                                                 reviewing, and evaluating the design, construction, and regulations
                                                                                                 needed for floodplain management, and also providing limited meas-
                                                                                                 ures of effectiveness.
                                                                                               � In many locales, floodplain development has been prevented or
                                                                                                 reduced in high hazard areas as a result of mapping and the establish-
                                                                                                 ment and enforcement of regulations.
                                                                                               � New development that meets commonly accepted flood-loss reduction
                                                                                                 standards has experienced greatly reduced losses.
                                                                                               � The institutional framework for floodplain management has been
                                                                                                 improved through an expanded legislative base, new agencies, and sup-
                                                                                                 portive judicial interpretations. There has been a shift away from fed-
                                                                                                 eral dominance toward a more equal partnership among federal, state,
                                                                                                 and local governments, and the private sector.
                                                                                               � A considerable amount of floodplain acreage, particularly wetlands,
                                                                                                 has been preserved by both the public and private sectors.

                60

                The Need for Specified Goals
                     No single piece of legislation or other authority outlines a compre-
                hensive set of measurable goals and objectives for floodplain management in
                the United States. Floodplain management would benefit from a set of speci-
                fied goals meant to be achieved by a certain date and whose success can be
                measured. Numerous national goals have been proposed by various govern-
                ment agencies and observers of floodplain management. Some examples of
                these suggestions are managing the natural resources of floodplains in con-
                junction with loss reduction efforts by the year 2000; moving people out of
                areas where they are continuously threatened by flooding; removing all resi-
                dences and commercial establishments from the 20-year floodplain by the year
                2020 and restoring these lands to their natural state; reducing losses to exist-
                ing buildings and infrastructure by requiring all federal agencies to assess the
                vulnerability to flooding of existing federal facilities and those state and local
                facilities constructed with federal aid; and reducing losses to areas and struc-
                tures outside regulated floodplams.

                The Need for a Comprehensive Data Base
                     There is a considerable amount of information about floodplain manage-
                ment available, but most of it was not collected with evaluation in mind; thus
                it is not precise enough to support judgments about the effectiveness of vari-
                ous floodplain management activities. This not only inhibits evaluation, but                          GISs AND THE FLOODPLAIN
                also hinders legislators, regulators, and other professionals in their efforts to                      MANAGEMENT DATA BASE
                establish, overhaul, or fine-tune programs and strategies to make them more                     Recent advances in the development and application
                effective. A mor .e complete data base will also give local government leaders a                ofgeographic information systems can improve the
                better opportunity to identify the public risks and costs associated with flood-                floodplain management d2ta base. With these sys-
                plain development.                                                                              tems, layers of information, such as thatfromflood
                     The obstacles  to developing and maintaining an adequate data base are                     insurance maps, cultural resource maps, and the
                substantial. Important determinations must be made about the type of data                       TIGER data system of the US. Census Bureau,
                to be collected, how often it should be collected, by whom, and using what                      can be combinedfor display, ana@sis, and manage-
                criteria. Adequate funding must be found.                                                       ment applications.
                     Additional information should be developed on several important topics,
                including an examination of the full benefits and costs, both public and pri-
                vate, of floodplain occupancy; an evaluation of the monetary benefits of main-
                taining the natural uses of the floodplain; and a determination of the steps
                needed to reduce the potential losses in the areas of the nation with the
                highest risk of catastrophic impacts from flooding.

                                     The Effectiveness of Management
                  Although a truly unified national program to manage floodplains is not
                yet in place, great strides have been made in that direction. The management
                framework has matured and expanded significantly since the 1960s. The
                growing recognition of the need for alternatives to federal investments in
                structural projects for flood loss reduction has been of particular importance.
                A major improvement was made in 1979, when protection of natural flood-
                plain resources was formally embraced. But the conceptual approach pre-
                sented in the current Unified National Program for Floodplain Management is still
                evolving. Further improvements could be made in the framework by develop-
                ing a clear definition of floodplain management and a set of measurable goals.
                Management efforts in general would be more effective if there were more
                flexibility for different approaches, smoother coordination among government
                agencies, and ways to account for local conditions.

                Allowing for Different Approaches
                     Many floodplain losses are of a sort that simply cannot be addressed
                through a by-the-book approach. For example, management techniques for
                such high risk flood problems as ice jams, flash floods, coastal flooding and
                erosion, mudslides, ground failure, alluvial fans, fluctuating lake levels, move-
                able stream beds, and areas behind unsafe levees or below unsafe dams, are
                not included in most local programs, which are designed to meet standardized
                National Flood Insurance Program minimum criteria. New methods for iden-
                tifying, mapping, and regulating areas with these flood hazards have been
                developed in some states- particularly in the arid West-through special
                                                                                                                                                            61

                                                                                      cooperative efforts with the Federal Emergency Management Agency. This
                                                                                      sort of flexible and innovative approach yields more effective management
                                                                                      in the long run. Incentives for communities to map and regulate high risk
                                                                                      hazard areas are now being provided through the Community Rating System
                                                                                      of the National Flood Insurance Program.
                                                                                            Another reason that management flexibility is needed is that the condi-
                                                                                      tions that cause floods do not recognize the political boundaries by which most
                                                                                      floodplain management techniques are applied. Many professionals believe
                                                                                      that comprehensive management based on hydrologic units must be made a
                                                                                      higher priority, especially if natural resources are to be protected. The river
                                                                                      basin commissions, the Environmental Protection Agency's National Estua-
                                                                                      rine Sanctuary Program, and the National Park Service's State and Local
                                                                                      River Conservation Program are examples of this technique. To facilitate
                                                                                      broader management, the states could enact legislation providing for regional
                                                                                      or watershed management, for river corridor management, and for other
                                                                                      regional efforts based on hydrologic and other natural boundaries rather than
                                                                                      political jurisdictions.

                                                                                      Coordination among Government Agencies
                                                                                            There is more coordination and better cooperation among all levels of
                                                                                      government now than there was 25 years ago, but improvements could still be
                                                                                      made. Each government agency involved with floodplain management has its
                        AGENCY AND ORGANIZATION                                       own legislative mandate and in general, each has been diligent in carrying out
                                  COORDINATION                                        that mandate within the imposed statutory limits. From the standpoint of an
                                                                                      overall federal program for floodplain management, however, there are many
                  Positive interagency coordination is exemplified by                 inconsistencies of purpose and procedure, overlaps, gaps, and conflicts. Some
                  professional groups like the Association o State
                                                          f                           of the inconsistencies can be reduced or eliminated by administrative action,
                  Floodplain Managers and the Association of State                    but some conflicts result simply from differing attitudes and expectations
                  Dam Safqy Officials, and bod2es like the Inter-
                  agency Committee on Dam Safety. Federal, state,                     about the ultimate responsibility and commitment of resources to respond
                  and local off@@ls, and representatives of the private               to flood problems, and these are not likely to be readily resolved. Neverthe-
                  sectorform the memberships of these groups, and they                less, a spirit of cooperation and common purpose can smooth many conflicts
                  have brought an important spirit of cooperation and                 and enhance existing efforts.
                  coordination that has been of tremendous benefit to
                  floodplain management over the past decade. They                    Providing for Local Conditions
                  met formally once a year and coordinate throughout                         Prescribing uniform national standards for the preservation, use, and
                  the year through subcommittee work- and special                     development of floodplains and other hazard areas for application at the local
                  projects.                                                           level can be inefficient and result in social inequities. Many of the existing
                                                                                      floodplain management tools are more easily applied in communities with
                                                                                      fairly high standards of living, where the local government has adequate staff,
                                                                                      resources, and expertise. This excludes many small rural communities and
                                                                                      economically disadvantaged areas. Natural resource preservation is a bottom
                                                                                      priority in low-income communities where a resident cannot even count on
                                                                                      the availability of potable water or sanitary facilities during and after a flood.
                                                                                      An awareness of local conditions could be incorporated into the national pro-
                                                                                      gram through wider use of performance standards, provisions of the Commu-
                                                                                      nity Rating System of the National Flood Insurance Program, and more flexi-
                                                                                      bility in the application of requirements for a positive benefit/cost ratio for
                                                                                      federal funding of flood control projects.

                62

                                                  The Effectiveness of
                              Floodplain Management Strategies and Tools

                        Additional accomplishments could be achieved through better or more
                  extensive use of the strategies and tools of floodplain management. Of the
                  four strategies, modifying flooding has traditionally been the most popular
                  because most of the planning, funding, construction, and implementation
                  for structural measures is carried out by the state or federal government,
                  and because local and individual adjustments or sacrifices are minimal. In
                  contrast, many measures to modify susceptibility to flood damages or to
                  modify the impacts of flooding are implemented on a structure-by-structure
                  or property-by-property basis and require constant vigilance, personal incon-
                  venience, and financial sacrifice. These drawbacks resulted in a lack of public
                  support for such measures in the past, and consequently local governments
                  were often reluctant to impose or enforce them. By the mid-1980s, however,
                  this impediment had been largely overcome and local officials began to focus
                  on how to comply with federal and state requirements and administer com-
                  munity programs to manage floodplains. Measures to modify susceptibility
                  to flood damage and disruption and to modify the impacts of flooding are
                  now widely accepted, even though some communities still have difficulty
                  administering them. The strategy of restoring and preserving the natural
                  and cultural resources of floodplains has had little exposure to date and
                  needs to be better integrated with the other strategies, both conceptually
                  and in practice.

                  Modifying Susceptibility to Flood Damage and Disruption
                        The tools used for this strategy have enjoyed widespread, fairly successful
                  implementation. Susceptibility to flooding in the United States is constantly
                  being effectively lessened at individual and local levels through the use of regu-                              REDUCING LOSSES THROUGH
                  lations, development policies, programs for disaster preparedness and assistance,                                      WARNING SYSTEMS
                  and warning systems. Evidence indicates, however, that overall vulnerability                               Annualflood damages in the Connecticut River
                  has either increased or stayed the same, probably because of the large amount                              Basin were reduced by $750,000 with aflood
                  of vulnerable development already in place, numerous exceptions to the state                               warning system that cost about $250,000 annual@.
                  and local policies that would reduce that development, and the fact that popu-
                  lation growth, movement, and urbanization sometimes take place so quickJy
                  or in such unexpected ways that adequate planning and regulation simply
                  cannot be established soon enough to prevent unwise use of floodplain areas.
                  This strategy may have the most potential for widespread future use, however,
                  because its tools can be coordinated well with other strategies and because it
                  provides an ongoing, more enduring way of adjusting to the flood hazard-
                  that is, altering human behavior usually before the losses occur.
                        Improvements could be made in the implementation of this strategy by
                        a improving the enforcement of floodplain regulations by local
                          governments;
                        0 reducing the usually unfounded concern of local and state officials that
                          strict floodplain regulations will be challenged as unconstitutional tak-
                          ings of private property;                                                                               FLOOD CONTROL INVESTMENT
                                                                                                                                             AND RETURN
                        0 minimizing flood damage to existing infrastructure and properly                                    The federal government spent over $13 billion for
                          designing and regulating future infrastructure that must be located in                             dams and otherflood control structures between
                          or near the floodplain; and                                                                        1936 and 1975. About $360 million had been
                        0 ensuring that current disaster assistance policies do not undermine                                expended on shoreline protection studies and projects
                          long-range floodplain management efforts.                                                          by 1985. In returnfor these investments, billions of
                                                                                                                             dollars in property damage have been avoided and
                  Modifying Flooding                                                                                         hundreds of thousands of people have been protected
                        National efforts to modify flooding have probably been more successful                               from anxiey, injury, and death.
                  than those directed toward any other strategy. The approach of controlling
                  floods is older than the other strategies, and over the course of five or six
                  decades countless floodprone situations have been alleviated with struc-
                  tural measures.
                        There is increasing recognition that the strategy of modifying flooding
                  can be counterproductive in at least two ways. First, it has been suggested
                  that the creation of structural protective works encourages development in the
                                                                                                                                                                                63

                                                                                          protected" area, resulting in increased vulnerability, perhaps not to the
                                                                                        design flood, but to larger ones or to unforeseen catastrophic events like struc-
                                                                                        tural failure. Second, structural measures can have adverse impacts on wildlife
                                                                                        habitat, scenic resources, and water quality, thus undercutting other flood-
                                                                                        plain management strategies.
                                                                                               Partly as a result of these concerns, there has been a considerable shift
                                                                                        away from reliance on structural solutions since the early 1960s. The planning
                                                                                        and installation of measures to modify floods, however, have not been aban-
                                                                                        doned. Flood control projects are still needed to complement the application
                                                                                        of other floodplain management strategies, particularly to protect existing
                                                                                        development.
                                                                                               There is an opportunity now to reformulate this strategy to acknowl-
                                                                                        edge its relationship to other techniques. Some of the tools to implement this
                                                                                        strategy, such as land treatment measures, on-site detention, and shoreline
                                                                                        protection, can be important components of comprehensive floodplain
                                                                                        management and resource protection programs.

                                                                                        Modifying the Impact of Flooding on
                                                                                        Individuals and the Community
                                                                                               The impacts of flooding on individuals and communities have definitely
                                                                                        been modified over the last 25 years, largely through increased awareness of
                                                                                        flood hazards as a result of the provision of information and education, and
                                                                                        because of the availability of flood insurance. After many years of counter-
                                                                                        productive effects, two of the tools for this strategy have recently undergone
                                                                                        basic revisions that may make them more effective at reducing future losses:
                                                                                        tax adjustments for flood losses have been reduced, and postflood recovery
                                                                                        measures designed to minimize future losses have been determined to be
                           THE EXTENT OF THE NFIP                                       an appropriate use of disaster assistance funds.
                   As of 1990, 82% of the nation's 20,000floodprone                            The implementation of this strategy could be improved by
                   communities hadjoined the National Flood Insur-                             0 expanding individual awareness of and knowledge about floodplains;
                   ance Program. In 1990, 2.39 millionflood insur-                             0 improving training programs for code administrators, planners, inspec-
                   ance policies were in force, proz. iding ozer S200 bil-                       tors, public works directors, and other local government personnel
                   lion in coverage. From 1978 to 1989, oier 384,000
                   flood damage claims had been paid, totalling about                            directly involved in floodplain management;
                   $3. 1 billion.                                                              * enlarging the premium base by increasing the number of insured
                                                                                                 structures, and thereby moving the National Flood Insurance Program
                                                                                                 closer to a fully actuarial basis; and
                                                                                               0 ensuring that postdisaster mitigation funds are used completely and
                                                                                                 creatively.

                                                                                        Restoring and Preserving the Natural and Cultural
                                                                                        Resources of Floodplains
                                                                                               As the latest addition to the array of floodplain management strategies
                                                                                        and the one least well-integrated with the others, it is not surprising that this
                                                                                        strategy has met with limited success. Floodplain land is being preserved in
                                                                                        a limited way through acquisition, public understanding and support for pres-
                                                                                        ervation and restoration of natural resources is growing, and mapping of the
                          PROTECTING RIVERS FROM                                        nation's wetlands is more than half finished. These accomplishments, how-
                                     ALTERATION                                         ever, have been the result largely of programs, policies, and efforts outside
                   As of 1990, 9,351 miles on 123 of the nation's                       the floodplain management arena. Regulations to protect and manage natural
                   rivers had been designated as wild or scenic, and                    resources in general are not well coordinated with those to reduce flood losses,
                   therefore protected underfederal law. But these pro-                 resulting in conflicts when implementation and enforcement are at stake. The
                   tected stretches are greatly outnumbered by the stream               strategy itself needs to be better integrated both with other floodplain manage-
                   segments that would be altered by proposed dams,                     ment tools and strategies and with compatible efforts in other fields, such as
                   channel modifications, and other projects.                           river corridor management, endangered species protection, and nonpoint
                                                                                        pollution control programs.

                 64

                                                                                                               INTEGRATING FLOOD LOSS
                                                                                                                REDUCTION AND NATURAL
                                                                                                                 RESOURCE PROTECTION
                                                                                                          Most localflood loss reduction programs focus
                                                                                                          primarily on the 100-yearfloodplain, while natural
                                                                                                          resource protection programs focus on a particular
                                                                                                          resource (wetlands, for example) which rwy or may
                                                                                                          not be located in thefloodplain. The two types of
                                                                                                          programs also are triggered by different events. Dis-
                                                                                                                                       a section 404
                                                                                                          aster relief is provided after a flood,
                                                                                                          permit is required when dredging orfilling is
                                                       @A
                                                                                                          planned; a wild and scenic river study begins after
                                                                                 A,                       Congressional action. These basic differences make
                                                                                                          integration of the programs difficult.

               The restoration and preservation of floodplains as natural resources is largely the result of efforts that are not
               well coordinated with the principal programs of)7oodplain managernent.
               Floodplain, Wildcat Falls, Joyce Ki&ner Memorial Forest, North Carolina.

                                              Conclusion

               Over the past 25 years, floodplain management has matured from a focus on
               reducing flood losses by using structural measures to a broader approach that
               incorporates structural and nonstructural measures for flood loss reduct    'on
               and also takes into consideration the protection of the natural and cultural
               resources of floodplains. The examples of flood damages averted, lives saved,
               and resources preserved are plentiful. It is evident that substantial progress
               has been made, and that diligent work is underway to remedy past shortcom-
               ings and reach even greater levels of achievement.
                    If current trends continue, the near future will see a further broadening
               of the scope of floodplain management to encompass such activities as storm-
               water management, greenway and river corridor management, and watershed
               management. Further integration of individual strategies and tools is likely, so
               that a more unified floodplain management program can emerge, with fewer
               conflicts among goals and activities. Technological advances also promise the
               improved application of existing strategies and tools.
                    A number of important opportunities are emerging for improving the
               future effectiveness of floodplain management in the United States. This
               report on the nation's floodplain management activities-the first compre-
               hensive assessment in over 25 years-has identified a plethora of actions to
               be pursued if significant improvements are to be made in floodplain manage-
               ment in the coming decade. Of these, two stand paramount: a simplification
               of the concept of floodplain management, and a set of specific national goals
               with a timetable for their achievement. These two needs should be addressed
               as the Federal Interagency Floodplain Managment Task Force undertakes to
               further refine the Unif@ed National Program for Floodplam Management.

                                                                                                                                                     65

                                 RETROSPECT AND PROSPECT

                                                               -an invited conwwnt by Gilbert E White

               This Assessment is unprecedented in its depth of analysis of the nature and
               effectiveness of the nation's management of floodplains. It is the most detailed
               and nearly comprehensive of all studies of those matters since the concept of
               floodplain management took official root in the mid-1960s. It places that con-
               cept in a broader context than ever before, and it provides a base for launch-
               ing a series of steps to assure that local and state as well as federal programs
               can at last approach the aspirations that have evolved over the past 65 years.
                  That evolutionary process has been reflected in a stream of laws, executive
               orders, regulations, new groups, and reports. Debate over the wisdom of reli-
               ance on simple levees and channel modifications began in the wake of the
               1927 flood on the Lower Mississippi. It widened to include issues of dams and
               economic justification after the Ohio River floods of 1936 and 1938 and a
               concurrent upstream versus downstream controversy over land treatment. By
               1966 a still broader view of the potential role of nonstructural measures found
               favor. Then followed a series of revisions and expansions of federal and state
               activities. Those included the National Flood Insurance Act of 1968, a
               National Science Foundation appraisal of flood research in 1977, a UnIfLed
               Natwnal Prograrnfor Floodplain Managermni in 1976, with revisions in 1979 and
               1986, three Executive Orders, a formal linkage with emergency management
               programs, and the organization of vigorous nongovernment groups such as
               the Association of State Floodplain Managers and the Association of State
               Wetland Managers. All of this and much more is examined in the Assess-
               ment. To sum up, the report tells the country what has been happening in
               floodplain management; how well or how poorly the responsible federal and
               state agencies have been doing; and what are promising means of improving
               the prospect. The result is the first thorough appraisal of ambiguous national
               aims and how those compare with the present situation on the lands at risk-
               the diverse areas of watercourses, adjacent wetlands, and the shores of
               streams, lakes, and oceans.
                  The report candidly recognizes the severe handicaps of incomplete and
               inconsistent collection of data on which policy judgments must be based. The
               data base is the one need specified in the 1966 House Document on which
               almost no action has been taken.
                  For other needs, the record of change has been diverse but generally posi-
               tive. In no instance, however, has achievement matched the hopes of earlier
               years. The definition of precisely what is meant by floodplain management in
               particular areas of the country or under the jurisdiction of specific agencies is
               still far from clear or uniform in either principle or practice. The policy goals
               for the sustainable use of floodplains have progressed in agency thinking but
               are proving difficult to meet in operation in the field. It has not been made
               clear how floodplain use is inseparably linked to the maintenance of natural
               resources for the common good for the foreseeable future. The effectiveness of
               individual federal and state programs, each with a different statutory
               authority, suffers thereby.
                  Cooperation among the administrators of federal programs, while generally
               cordial and helpful, has not yet yielded a genuinely unified effort. Lacking
               exemplary effectiveness at that level, state and local agencies cannot be
               expected to act in concord in meeting national goals.
                  Great gains have been made in public information and education. Far more
               legislators, administrators, business executives, farmers, householders, and
               school children are aware of flood hazards than a decade ago. The level and
               quality of information, however, still is far below what would be required to
               induce effective action in the event of a threatening flood, and even more so
               in the days when measures are needed to mitigate future emergencies.
                  Flood forecasting precision has generally improved. The demonstrated
               ability of communities to respond positively to a warning is less certain and
               is uneven.

                                                                                                                                                     67

                                                                          The report suggests lines along which improvement can be brought about
                                                                        and recommends consideration of a number of changes in policy and proce-
                                                                        dure. The report's Review Committee does likewise with its Act in Agenda for
                                                                        Managing the Nation's Floodplains. These must be examined now against the back-
                                                                        ground of experience with previous statements of optimal floodplain policy,
                                                                        such as House Document 465 or the Unifi6d Natiqn@ Program for Floodplain
                                                                        Management. Only fragments of those proposals were adopted. Can anything be
                                                                        learned from the conditions that either promoted or blocked them? What are
                                                                        the factors in climate of public opinion and in government organization that
                                                                        worked for or against them at that time and that may have changed
                                                                        subsequently?
                                                                          It is evident that the reconciliation of thinking among professional groups,
                                                                        for example, has been advanced by research, conferences, training, and publi-
                                                                        cations. Hydrologists, engineers, geographers, economists, land planners,
                                                                        ecologists, city managers, insurance executives, and disaster relief directors,
                                                                        among others, now are speaking the same language. But there are at least
                                                                        three directions in which lessons learned are still not practiced.
                                                                          One important lesson is that quick and nation-wide change in procedures
                                                                        without careful trial in selected areas and without subsequent critical
                                                                        appraisal can be counter-productive. When the Tennessee Valley Authority
                                                                        established its community assistance program for flood damage prevention
                                                                        planning in 1953 and the Corps of Engineers introduced its floodplain
                                                                        management services program in 1960, they moved cautiously and employed
                                                                        a variety of trial approaches. In contrast, when national flood insurance was
                                                                        introduced in 1968 there was a brave commitment to offer coverage to all
                                                                        parts of the country at once. Little attention was given to post-audits of the
                                                                        rates, terms of insurance, map adequacy, and relation of detailed regulations
                                                                        to local physical and social conditions. As a result, the Federal Insurance
                                                                        Administration found itself locked into sometimes unwieldy or ineffective
                                                                        procedures that might well have been avoided in the light of experimentation.
                                                                        The attempt in the late 1970s to set up a nation-wide floodplain map file was
                                                                        likewise an unfortunately hasty enterprise. In its 23 years of operations, the
                                                                        National Flood Insurance Program has achieved much and continues to gain
                                                                        new experience. The current implementation of the Community Rating Sys@
                                                                        tem now offers special opportunities to appraise the suitability of national
                                                                        standards and procedures at the local level. As new improvements are made
                                                                        in federal programs, it will be important to craft them on an experimental
                                                                        basis with careful provision for evaluation as they are launched.
                                                                          A second lesson derives from the contrast over the years between expres-
                                                                        sions of desirable unified policy and measures to, in practice, unify the activi-
                                                                        ties of agencies which in theory subscribe to the policy. There has been nei-
                                                                        ther a single statement of Congressional intent with respect to floodplain
                                                                        management similar to the Earthquake Hazards Reduction Act of 1977, nor a
                                                                        delegation to a single executive agency of responsibility for coordination of the
                                                                        various federal programs. The Bureau of the Budget was interested in such
                                                                        coordination in the mid-1960s but did not take a strong hand. The Water
                                                                        Resources Council served as a meeting place of interested agencies without
                                                                        having statutory authority. After the council disbanded in 1982 it was followed
                                                                        by the Interagency Task Force, a voluntary group that also lacked authority to
                                                                        enforce desirable action as outlined in three Executive Orders. It cannot be
                                                                        expected that conscientious administrators will abandon their own statutory
                                                                        authority and responsibility before joining cooperative ventures, no matter
                                                                        how desirable the goals. It is just as clear that unless a strong statement is
                                                                        made by the Congress on the ways in which the basic policies of the individ-
                                                                        ual federal agencies are to be related to the underlying aims in managing
                                                                        floodplain resources, those policies will have little significance in the field,
                                                                        where they influence or are constrained by state and local practices.
                                                                          The third major lesson is that floodplain policy changes must be taken in
                                                                        the context of broad environmental goals applied to local conditions. This was
                                                                        the case in the unfolding of the Coastal Zone Management Act where four
                                                                        federal agencies have joined in a partnership for action on habitat protection,
                                                                        nonpoint source pollution management, and sediment control. It occurs in
                                                                        the implementation of soil conservation programs on lands where environ-
              68

                mental integrity must harmonize with economic considerations. It is acutely
                the case in the delineation of wetlands, where the rigidity of proposed national
                criteria confronts wide variety in interpretation of suitable floodplain use.
                Coastal erosion raises similar issues. The reconciliation of multiple and some-
                times inconsistent national goals is an endemic problem in resource manage-
                ment. It can only be achieved effectively by dealing with particular landscapes
                in particular regions. When national goals shift or are clarified, as they surely
                will, the complexity increases. Unless floodplain management practices take
                into account local food and fiber production, biota, water supply, urban land
                use, recreation, and more-in addition to flood loss reduction-the goals for
                maintaining the sustainability of floodplains will surely not be met.
                  Experience over the past 25 years suggests that to help achieve the improve-
                ments in prospect will require a willingness to test and appraise new pro-
                grams, a Congressional definition of unified federal policy, an executive decl-
                sion to assure the coordination of the federal agencies, and a commitment by
                representatives of the principal state, local, and nongovernment groups to col-
                laborate in adapting national aims to local conditions where the benefits will
                be seen-on the borders of the nation's rivers, lakes, and coasts. Without
                these measures, the resources of those areas will remain unduly vulnerable to
                natural extremes in stream flows and tides, and the people of this nation will
                receive less than optimal benefits from floodplains' amenities, soil, water, and
                biota.

                Gilbert E While has been observing the nation's floodplains for over 50years. He is a Distinguished
                Service Proftysor Enwritus of Geography and thefounder andformer director of the Natural Hazard@
                Research and Applications Information Center at the University of Colorado. He was chair of the Task
                Force on Federal Flood Control Polky, 1965-66, and of the National Review Committee established in
                1989 to assist in carrying out the assessment surnmarized in this volume.

     10

                                                                                                                                                     79

                                                                                                Photo Credits.
                                                                                                Cox=Bob Cox, Floodplain Management Section, Louisiana Department of Transportation and Development
                                                                                                Corps= U. S. Army Corps of Engineers
                                                                                                EPA= US Environmental Protection Agency
                                                                                                TVA=Tennessee Valley Authority
                                                                                                FEMA=Federal Emergency Management Agency
                                                                                                NHRAIC=Natural Hazard Research and Applications Information Center
                                                                                                Note. -Many of the photographs credited to the TVA were originally provided by other federal and state agencies to
                                                                                                the TVA for presentations by that agency. Wherever possible, additional credit is given; in some cases, however,
                                                                                                the original donor could not be determined.
                                                                                                p. 7 John McShane, FEMA; pp. 9-10 (all photos), Cox; p. 11 (top right), EPA; p. 11 (bottom right),
                                                                                                Merrimack River Watershed Council; p. 11 (left), Cox, p 12 (right and bottom left), Cox; p. 12 (top left),
                                                                                                NHRAIC; p.13 (top), Colorado Department of Disaster Emergency Services; p.13 (bottom), TVAIArizona
                                                                                                Department of Water Resources; p.14, (top), Cox; p.14 (middle), Corps; p.14 (bottom), TVAISouth Carolina
                                                                                                Water Resources Commission; p.15 (right), TVA/California Department of Water Resources; p.15 (left),
                                                                                                TVAIWashington State Department of Ecology; p. 16, Corps; p. 17 (left and right), Corps; p 18 (top),
                                                                                                NHRAIC p.18 (middle), Cox; p.18 (bottom), TVAIMassachusetts Division of Water Resources; p.19 (top),
                                                                                                TVA, p. 19 (bottom), TVA/EPA; p. 20 (top right), Cox, p. 20 (top left), TVA/Massachusetts Division of
                                                                                                Water Resources; p. 20 (bottom left), Cox; p. 21 (top right), Cox; p 21 (bottom right), EPA; p. 23
                                                                                                TVA/Corps; p.24 (both photos), NHRAIC/Corps-Pittsburgh Office; p.26 Cox; p.34, Corps-Vicksburg Office;
                                                                                                p.35, Corps-Vicksburg Office; p.37 Corps; p.38, TVA/Utah Department of Public Safety; p.39, TVA
                                                                                                /Massachusetts Division of Water Resources, p.40, NHRAIC, p.43 (top), Corps; p.43 (bottom), TVA/Utah
                                                                                                Department of Public Safety; p.44, Cox; p.45, EPA; p.47 Corps; p.48, TIA; p.51, Corps; p.52, FEMA
                                                                                                p55 (top), Cox; P.55 (bottom), TVA/Texas Water Commission; P.56, FEMA; p.65, Cox.

                                                                                                                                                                                                          Back cover:
                                                                                                                                                                          Illustration of some flood consequences and
                                                                                                                                                             floodplain management measures. Clockwise from top.
                                                                                                                                                          1. Flood water detention. 2. Regulations and development
                                                                                                                                                            policies. 3. Information. 4. Coastal protection. 5. Flood
                                                                                                                                                                 emergency measures. 6 Natural protection systems,
                                                                                                                                                                   7 Preserving natural resources. 8. Mapping flood
                                                                                                                                                                               hazard areas. 9. Structural elevation.

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