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









                                        CITY OF HAMPTON

                                        CHESAPEAKE BAY

                               PRESERVATION AREA PROGRAM

                                                FINAL

                                            AUGUST 1990























                                                                






                                           PREPARED BY


	
								MAI

		


            QH                          MAGUIRE ASSOCIATES INC.
            541.5                      770 LYNNHAVEN PARKWAY
            .E8                                  SUITE 240
            C48
            1990                        VIRGINIA BEACH, VA 23452










                                                               CITY OF HAMPTON


                                    CBESAPEAKE BAY PRESERVATION AREA PROGRAM


                                                             TABLE OF CONTENTS



                1.        EXECUTIVE SUMMARY


                II.       INTRODUCTION


                III.      CHESAPEAKE BAY PRESERVATION AREAS


                          A.        COMPONENTS
                          B.        DEFINITIONS
                          C.        VALUES


                IV.       ENVIRONMENTAL INVENTORY


                          A. METHODOLOGY
                          B.        MAPPING
                          C.        DESIGNATION


                V.        CHESAPEAKE BAY PRESERVATION AREA OVERLAY DISTRICT MAPS


                VI.       LITERATURE CITED









                                     ACKNOWLEDGEhIENTS
                This report was produced in part through financial support from the Virginia
          Council on the Environment pursuant to the Coastal Resources Program, Grant No.
          NA89AA-D-D2-134 from the National Oceanic and Atmospheric Administration.









                                 ABBREVIATIONS AND ACRONYMS



           Chesapeake Bay Local Assistance Board             CBLAB

           Chesapeake Bay Local Assistance Department        CBLAD

           Chesapeake Bay Preservation Act                   ACT

           Chesapeake Bay Preservation Area                  CBPA

           Resource Protection Area                          RPA


           Resource Management Area                          RMA

           Intensely Developed Area                          IDA

           Chesapeake Bay Preservation Area            "Regulations"
           Designation and Management Regulations









             L      EXECUTIVE SUMMARY


                    The Virginia General Assembly has enacted a number of initiatives to protect and
             restore state waters, ranging from incentive programs to specific delegation of authority
             to local governments. The most significant of these is the Chesapeake Bay Preservation
             Act, which serves to greatly expand local police powers and provide a means of better
             utilizing state resources. The Chesapeake Bay Preservation Act establishes a specific
             relationship between water quality protection and local land use authority. Pursuant to
             Section 10.1-2108 of the Code of Virginia: "counties, cities and towns are authorized to
             exercise their police and zoning powers to protect the quality of state waters consistent
             with the provisions of this chapter." The regulations adopted pursuant to the Act draw
             heavily upon the powers conferred to local governments and seek to build on the
             foundation of other state water quality protection initiatives.

                    The General Assembly has encouraged local governments to make full use of the
             significant expansion of authority and responsibility conferred by the Act. Accordingly,
             water quality protection is to be more closely considered in land use decisions, policy, and
             ordinances.


                    The state-local cooperation envisioned by the Act hinges on timely local
             implementation of the Criteria Regulations promulgated by the Chesapeake Bay Local
             Assistance Board (CBLAB). The Act requires localities one year after the adoption date
             of the Regulations (September 20, 1989) to designate Chesapeake Bay Preservation Areas
             (CBPAs) within their jurisdictions. Localities are further required by the Act to employ
             measures necessary to implement the CBLAB's performance criteria. These requirements
             are considered the two principal elements in the first-year program of.the Bay Act.

                    The City of Hampton began updating its Comprehensive Plan for 1990 following
             the adoption of the Regulations. In February, 1990 the City of Hampton contracted with
             Maguire Associates, Inc. to assist in the implementation of the first-year program of the
             Bay Act. This report addresses the first-year program element of designating CBPAs
             within the City of Hampton. Upon comp-letion, the City of Hampton will incorporate this
             element into its Comprehensive Plan.










            11. INTRODUCTION


                   In order to satisfy the requirements of the first-year program, specifically the CBPA
            designation, a series of objectives was established by the City. The primary objectives of
            this Report are to:

                   1)     Identify and delineate componentsof a Chesapeake Bay Preservation Area
                          including tidal wetlands, tidal shores, non-tidal wetlands hydrologically
                          connected by surface flow and bordering on tidal wetlands or tributary
                          streams, tributary streams, and buffer areas.

                   2)     Categorize the above components into Resource Protection Areas (RPAs)
                          and Resource Management Areas (RMAs).

                   3)     Provide an Environmental Inventory including the mapping and
                          documentation of the above designations investigated in the Report.

            In order to meet these objectives, a number of interrelated tasks were undertaken. A
            brief description of each task is provided below.

                   LITERATURE SEARCH AND REVIEW


                   Collection and review of pertinent resource data including statistics, maps,
                   photographs, surveys and environmental reports relevant to the City.

                   FIELD INVESTIGATIONS


                   Reconnaissance survey of environmental resources identified in the literature. Field
                   verification of resources previously delineated by the City of Hampton.

                   DATA ANALYSIS


                   Analysis of data collected through the literature and field investigations.
                   Comparison of data with existing environmental resource inventories and mapping.

                   PRELIMINARY MAPPING


                   Preliminary delineation of environmental resources on planimetric drawings.
                   Refinement of delineation based on field and office evaluations.









                 PRESERVATION AREA DESIGNATION


                 Designation of preservation areas based on preliminary mapping of environmental
                 resources.


                 FORMAL MAPPING AND REPORT PREPARATION


                 Mapping and categorization of preservation areas into Resource' Management
                 Areas and Resource Protection Areas. Preparation of Report including a discussion
                 of the methodology, mapping, and designation process.








































                                                H - 2









            III. CHESAPEAKE BAY PRESERVATION AREAS


                   The Chesapeake Bay Preservation Act requires each local government to designate
            CBPAs encompassing those land features which, if improperly developed, would contribute
            to the significant degradation of the water quality of the Bay and its tributaries. Some
            land features within the shoreline environment, such as wetlands, serve an important and
            direct water quality function in their own right by removing excess sediment, nutrients and
            potentially harmful or toxic substances from the runoff entering the Bay and its tributaries.
            Other features, such as floodplains, have a great potential to degrade water quality if they
            are improperly disturbed or developed. Thus, in developing the Regulations the CBLAB
            recognized the functional difference between two types of lands.

                   A. COMPONENTS


                           For all local governments, including Hampton, lands which have intrinsic
            water quality benefit are designated RPAs. Those lands which have the potential of
            degrading water quality or diminishing the functional values of the RPA, if not properly
            managed, are designated RMAs.

                   For the purposes of this report, all tidal wetlands, tidal shores, tributary streams,
            and non-tidal wetlands hydrologically connected by surface flow and bordering on tidal
            wetlands or tributary streams, as well as a 100-foot buffer area landward of these
            components are designated as RPAs. These lands perform important water quality
            protection functions by absorbing wind and wave energy, stabilizing soils, and filtering
            sediment and nutrients running off the land. The RPA constitutes the last barrier to the
            overland flow of runoff before it reaches surface waters. Because of their vital ecological
            importance, RPAs will be the most stringently regulated portion of CBPAs.

                   Further, land features such as drainage basins and floodplains are designated as
            RMAs. An RMA is designated contiguous to the entire inland boundary of the Resource
            Protection Area.


                   Inappropriate land use and development practices in the RMA may have an
            adverse impact on the water quality protection function of the RPA. It is therefore critical
            that the RMA encompass an area large enough to provide significant water quality
            protection through the employment of the performance criteria.

                   B.     DEFWITIONS


                          The words and terms used in the "Regulations" have been carefully defined
            to convey the desired meaning. Many of these definitions are specific to the "Regulations",
            while others are derived from terms already employed in other water quality programs.








                    For example, there are several conceivable definitions for tidal shore, depending on
             the situation. The level of biological activity is highest in the littoral zone, that is, the
             shallow-water habitats which fall seaward of low-water. However, these submerged lands
             are generally state-owned lands beyond local government jurisdiction. The definition which
             the criteria employ (mean low water to mean high water level) tracks the language of the
             Tidal Wetlands Act (Section 62.1-13.2 et s?A. of the Code of Virginia).

                    To provide the reader with the rationale and justification for the way Preservation
             Area components are defined in the Regulations, explanatory text is provided below.

                           1. Tributary Streams. The Regulations define tributary streams as "any
             perennial stream" since the connection of such streams to the Bay is a major pathway by
             which pollution enters the Bay. The definition is tied to the depiction of these features
             as they appear on the U.S. Geological Survey 7-1/2 minute topographic maps. USGS
             quad maps are recognized as being reasonably accurate and readily available. There are,
             however, certain limitations due to the map scale. For example, some drainage ditches
             may appear as perennial steams.          Further, this scale (1:24,000) allows only an
             approximation of where a perennial stream stops and intermittent flow begins. More
             detailed information from other local maps or field reconnaissance may be used to
             supplement USGS quad sheets as necessary in designating tributary streams.

                           2. Tidal Shores. The Regulations define tidal shores as "land contiguous
             to a tidal body of water between the mean low water level and the mean high water
             level".


                           3. Tidal Wetlands. To ensure consistency, the definition for tidal wetlands
             in the Regulations is the state regulatory definition (Section 62.1-13.2 et seQ. of the Code
             of Virginia). This is the same definition as applied by the Virginia Marine Resources
             Commission and the Hampton Wetlands Board.

                           4. Non-Tidal Wetlands. Non-tidal wetlands are defined as those wetlands
             other than tidal wetlands that are inundated or saturated by surface or ground water at
             a frequency and duration sufficient to support, and that under normal circumstances do
             support, a prevalence of vegetation typically adapted for life in saturated soil conditions,
             as defined in the Federal Manual for Identifying and Delineating Jurisdictional Wetlands
             (1989).

                    It is important to note that all three attributes of the definition - wetland
             vegetation, undrained hydric soils, and wetland hydrology must be satisfied in order to
             classify an area as non-tidal wetlands. Since the Regulations' definition is the same as that
             used in the Federal Manual, wetlands included within CBPAs are likely to be under
             Federal jurisdiction.


                                                        III - 2








                           5. Floodplains. The 100-year storm return interval is used to define
            floodplains in the Regulations since this is the return interval used in the federal flood
            insurance program in which most local governments participate.             Further, 100-year
            floodplain maps are relatively common as a result of that program. It should be noted
            that floodplains are land areas that are inundated by the overflow of streams and rivers,
            not drainage ditches. A regulatory floodplain is frequently defined by state and local
            regulations to include all land within reach of a 100-year flood, that is, a flood with a one
            percent probability of occurring in any given year.

                           6. Highly Erodible Soils. The Regulations define highly erodible soils by
            the incorporation of a formula that accounts for most of the characteristics that actually
            result in excessive soil erosion including, the effects of the interaction of rainfall, the
            erodibility factor, slope gradient, and slope length. This formula is familiar to soil
            scientists and soil conservationists. Using this definition will also permit areas of highly
            erodible soils to be easily mapped from digital soil data. Also important is the fact that
            the definition is consistent with the definition used in Virginia to identify highly erodible
            agricultural soils for determining compliance with requirements of the 1985 Federal Food
            Security Act (Farm Bill).

                           7. Highly Permeable Soils. The definition of highly permeable soils is based
            upon recommendations by the U.S. Department of Agriculture - Soil Conservation Service
            and is consistent with SCS's classification system. Again, the use of this definition will
            allow highly permeable soils to be easily mapped from digital soil data.

                   The SCS estimates that this definition (six inches per hour) describes approximately
            30% of coastal plain soils, whereas, the next lower mapping break-point - moderately
            rapid (two inches per hour) - describes approximately 75-80 % of the land in Tidewater
            Virginia.

                           8. Buffer Areas. The Regulations define buffer areas as "an area of natural
            or established vegetation managed to protect other components of a RPA and state waters
            from significant degradation due to land disturbances. The Act defines CBPAs as "certain
            lands... which if improperly developed may result in substantial damage to the water
            quality of the Chesapeake Bay and its tributaries." At first glance, this broad definition
            might seem to include virtually all of Tidewater Virginia, since any land improperly
            developed will contribute to water quality degradation.

                   The key to understanding this definition, however, is the meaning of "substantial"
            damage. Clearly there are lands which have greater potential for water quality impact
            than others. In fact, the Regulations recognize two distinct types: those which intrinsically
            protect water quality (RPAs) and those which have the potential, by their nature, to cause
            serious negative impacts if used or developed improperly (RMAs).


                                                       III - 3








                    Thus the Regulations work to prevent water quality degradation on two levels:
            protecting the viable water quality function of certain lands and preventing negative
            impacts from others.

                    RPAs perform natural pollution control functions. Biological activities in these
            areas are specially adapted for controlling runoff, trapping sediment, and recycling
            nutrients and pollutants. By virtue of their proximity to water courses, RPAs provide the
            last line of defense before pollutants enter the Bay and its tributaries.

                    The second class of lands, RMAs, are prone to amplifying the impacts of pollutants.
            Highly erodible soils, steep slopes, highly permeable areas, floodplains, and certain
            wetlands accelerate the process of pollutants reaching ground water and surface water.
            Their characteristics cause them to have a greater potential for pollution as a result of
            improper development practices.

                    The types of lands which    have been identified as CBPAs are important features
            in the hydrologic cycle and, as such, have direct and substantial links to water quality. The
            Regulations have been designed to recognize this relationship as a means to achieving
            enhanced water quality in the Bay.

                    C. VALUES


                           1. Wetlands. Wetlands, which include marshes, swamps, bogs, pocosins
            and wet meadows, are transition areas between drier uplands and the deep waters of
            streams, rivers, lakes and bays. In recent decades, the ecological values of wetlands have
            become better understood. Nevertheless, wetland loss has been a major contributor to
            water quality damage. Between 1956 and 1977, over 63,000 acres of Virginia's wetlands
            were lost at an average annual rate of over 3,000 acres. Since they are linked to both
            upstream and downstream ecosystems, wetlands play key roles in regional hydrologic cycles,
            and their functional values may extend well beyond the boundaries of the wetlands
            themselves. (The Conservation Foundation, 1988).

                    Wetlands benefit water quality by acting as a filter in trapping and holding nutrients
            and microbes which come from upland runoff. Aquatic plants in wetlands change
            inorganic nutrients into organic material, storing it in their leaves or in the peat soil
            composed of their remains. The stems, leaves and roots of wetland plants also slow down
            and trap sediment, so the wetland acts as a settling basin, keeping downstream water clean
            by holding back silt and other insoluble material. Toxic chemicals and other pollutants
            which are washed in with sediment can be caught by this filtering process as well
            (Hershner, 1989).




                                                        III - 4







                    Wetlands also act as a sponge by slowing down fast-moving erosive water, absorbing
            the energy of it for flood control and storm-damage protection, and acting as a buffer
            against coastal erosion from wave action. Water is stored in the highly absorptive soils
            of wetlands, which serve as reservoirs from which groundwater can be replenished during
            dry seasons (ThuTow, 1975).

                    Wetlands are more sensitive than deeper water to pollution because the exposure
            of their larger relative surface area to wind movement and the sun's warmth speeds up
            the chemical processes taking place in the water. Development overloads and degrades
            the natural filtering system by accelerating the natural process of silting, often adding
            pollutants as well. Wetlands have a threshold of tolerance for what they can effectively
            assimilate; beyond that threshold, they will no longer have the same filtering and water-
            storing capacity. Wetlands cannot function as bottomless settling basins and must be
            protected from pollution and sediment flow in order to maintain their value. The ecology
            of wetlands is also disturbed by exaggerated high and low water levels caused by increased
            stormwater runoff and pumping for irrigation and water supplies (Thurow, 1975).

                    Wetlands are either tidal or nontidal depending on their proximity to tidal waters,
            such as bays and oceans. Tidal wetlands include marshes and salt ponds, and nontidal
            wetlands are generally inland areas such as forested swamps.

                    Tidal wetlands, which include vegetated marshes and nonvegetated sandflats or
            mudflats, are the most easily recognized of the wetlands in the coastal area. They are
            dominated by tidal action which regularly floods them. Typically, these wetlands are found
            along the coast but they may also be found along creeks and rivers which are influenced
            by tides although they are distant from the coast. Thus, tidal wetlands may be either salty
            or fresh depending on their proximity to the coast and the amount of freshwater entering
            them (Rice, 1987).

                    Both vegetated marshes and non-vegetated mudflats protect the shoreline and
            adjacent upland by reducing erosion caused by wave action. They also filter pollutants and
            excess sediment carried to the shore by estuarine waters.

                           2. Tidal Shores. The shoreline interface where the water meets the land
            is the scene of dramatic changes caused by the natural forces of wind and water. As a
            result of the impacts associated with seasonal tidal fluctuations, hurricanes, tropical storms,
            and "northeasters", wind and water-generated wave action displaces shore sediments
            through erosion and transports them from place to place through the process of
            deposition. In this manner, the shape and make-up of the tidal shore is constantly in a
            state of change.




                                                         III - 5








                    Tidal shore stability is generally governed by three main determinants: the amount
            and type of materials making up the beach, the intensity of the natural and human forces
            responsible for change, and the stability of sea level.

                            3. Buffer Areas. Recent developments in land use planning techniques
            have recognized the benefits that arise from the use of vegetative buffers in screening or
            separating incompatible land uses. Such buffers are most commonly associated with
            screening wind, noise or unsightly views, but buffers can be particularly effective as well,
            in filtering stormwater runoff from disturbed sites.

                    Buffer areas are zones of undeveloped, vegetated land that are managed to reduce
            the impact on water quality of land disturbing operations in adjacent areas. The buffer
            area can either be spatially arranged as a linear strip or as a free-form mass of vegetation,
            depending upon the desired use for which the buffer is intended. Similarly, buffer areas
            can be naturally existing zones of vegetation or planted zones of vegetation, depending
            upon the character of the site and the extent of site disturbance.

                    Vegetated buffer areas provide a wide variety of environmental, aesthetic, and
            recreational benefits. Benefits that can be derived from the implementation of buffer
            areas include   the following:

                            -  Sediment control
                            -  Nutrient assimilation
                            -  Streambank stabilization
                            -  In-stream temperature maintenance
                               Outdoor recreation
                            -  Flood control/protection
                            -  Groundwater recharge area protection
                               Aesthetics protection
                            -  Runoff volume reduction


                    Although all these benefits are important, the benefit perhaps most notable in terms
            of water quality protection is the potential for filtering sediment and assimilating nutrients
            from surface runoff caused by storms.

                    Buffer areas provide the moderating effects of vegetation, protective soils, and
            organic litter to slow down the rate of stormwater runoff and protect nearby population
            centers from the hazards of flooding associated with high rates of runoff. Buffers slow
            down runoff from impervious surfaces, thus allowing more consistent flows in water-
            courses and the continued renewal of groundwater storage areas. And finally, buffer areas
            provide a margin of safety by protecting watercourses form the degrading influence of
            sedimentation and pollution.


                                                        III - 6








                   The Regulations require that a buffer area not less than 100 feet wide be located
            adjacent to and landward of tidal shores, tidal wetlands, nontidal wetlands connected by
            surface flow and contiguous to tidal wetlands or tributary streams, and along both sides
            of any tributary stream.

                   Tributary streams are an integral part of an area's watershed, which is the land area
            drained by a river (or, in Tidewater Virginia, by the Chesapeake Bay) and by small rivers
            and streams which feed into the river.
















































                                                       LH - 7









            IV. ENVIRONMENTAL INVENTORY


                 The Regulations require an inventory of certain key features that are components
            of CBPAs. In order to prepare the inventory a number of guidelines were followed to
            designate preservations areas within the City of Hampton.

                 An environmental inventory usually consists of information gathered and presented
            on map form. Accordingly, a series of maps were prepared delineating the location of
            resources and problem areas. According to the Regulations, the following environmental
            features were identified:


                       Tributary Streams

                       Tidal Shores

                       Tidal Wetlands

                       Non-tidal Wetlands

                       Buffer Areas


                 An environmental inventory helps identify natural and living resources in the
            community. It also indicates how these resources may constrain future development and,
            in turn, what impact development may have on their long term viability. It also further
            delineates areas with features of special planning interest. Finally, the environmental
            inventory provides information critical to the City in its endeavor to balance the value of
            anticipated growth and ec*onomic development with the value of natural features and
            environmental resources.


                 A. METHODOLOGY


                       The inventory of the environmental features was accomplished through the
            following methodology. First, current mapping and literature of pertinent environmental
            features were obtained and reviewed. As part of the effort, the following resources were
            secured:


                 U.S. Geological Survey (USGS) topographic maps - Norfolk North, Newport News
                 North, Newport News South and Hampton, VA quadrangles. Scale: 1"=2000'

                 National Oceanic and Atmospheric Administration (NOAA) navigation charts.
                 Variable scales.





                                                       IV - 1








                 National Wetland Inventory (NWI) maps - Newport News North, Newport News
                 South and Hampton, VA quadrangles. Scale: 1"=2000'.

                 Virginia Institute of Marine Science (VIMS) Tidal Marsh Inventory - City of
                 Hampton. Scale: 1"=2000'.

                 Federal Emergency Management Administration (FEMA) floodplain maps. Scale 1"
                 = 400'.


                 Aerial photographs from the City of Hampton, Virginia Department of
                 Transportation, and the Norfolk District, Corps of Engineers.

                 Subsequently, the above data were carefully reviewed and compared with existing
            coastal resource information for general accuracy and consistency. The information was
            then transferred to a working drawing (blueline) for each planimetric sheet (e.g. B-7, H-
            2, etc.). This transfer was accomplished by first modifying the scale of the pertinent
            resource map to that of the working drawing, i.e. 1" = 200', and then overlying the latter
            on the former map. Information was then traced to the working drawing and properly
            identified and roughly delineated to allow for field verification and fine tuning of the
            delineation.


                 After environmental information was transferred to each working drawing, a
            reconnaissance survey of the entire City was conducted. Working drawings, resource maps
            and aerial photography were taken in the field and utilized to confirm and/or refine
            environmental resource boundaries. Once the pertinent environmental features were field
            verified, all information was properly delineated and identified on the working drawings.
            Once the features were delineated, the working drawings helped form the environmental
            inventory.

                 As noted earlier, the delineation of environmental resources was based on existing
            data, mapping resources, and field verification. There are certain limitations in the
            accuracy of these resources due to scale and methodology.            In addition, certain
            environmental features have been altered or no longer exist, therefore, mapping may not
            represent current conditons throughout the City.        Nevertheless, the environmental
            inventory provides an important tool for local land use planning and, as such, are
            appropriate for the designation of Preservation Areas.

                 The majority of these mapping resources were available at a scale of 1:24,000 (1"
            2000'), which facilitated the preparation of overlays of environmental features. Some of
            the available mapping projects, like the USGS topographic maps were widely used. Other
            available mapping resources are less familiar, or present a new resource to localities.



                                                      IV - 2








                 Although the Management Regulations do not dictate a map scale for the designation
            of CBPAs, the City of Hampton elected to prepare their designation maps at a scale that
            provided the best fit with their comprehensive plan, zoning map, tax maps, and local
            topographic mapping. For most governments, the 1:24,000 scale will generally be
            adequate. For urban and rapidly developing suburban localities, more detailed mapping
            of Preservation Areas is more desirable.


                 The scale of the final map or maps designating CBPAs is in large part dependent
            upon the performance criteria the City plans to implement at the end of the first year.
            Since the City of Hampton will implement the criteria via an overlay zoning district
            approach, it prepared maps at a scale consistent with the zoning map. For this project,
            CBPAs were designated on an overlay at a scale of 1" = 200'.

                 With the preparation of the inventory and the introduction of improved information
            as it becomes available, the City of Hampton will have a comprehensive environmental
            information base to use in all of their land use planning efforts. As time and staff
            resources permit, additional analyses can be undertaken which, in turn, will enhance this
            important information resource.



                 B. MAPPING


                      The following section describes the guidelines that were implemented in formally
            mapping individual features as components of CBPAs. The guidelines address the use
            of existing mapping resources available for this effort. The USGS topographic maps and
            NWI maps were the most fundamental and practical maps used. USGS topographic maps
            were very helpful in showing contours and the shape of the City's terrain. The NWI maps
            were equally helpful in locating and delineating the City's wetlands, both tidal and non-
            tidal.


                 Once the relevant environmental features were labelled and delineated, data from the
            working drawings were transferred to mylar overlays at the same scale. Consistency in
            format was essential to provide meaningful mapping for the following resources.

                      1.   Tributary Stream . Tributary streams were reasonable place to begin the
            mapping process, as they provided the "skeleton" for RPA boundaries and provided linkage
            to the other environmental resources. Where other RPA features did not exist, the RPA
            consisted of the 100-foot buffer area along both sides of the tributary stream.

                 Identifying and mapping tributary streams was not a complicated process, since they
            were clearly marked on USGS topographic quadrangle maps. On USGS maps, the Bay
            and its tributaries are shown in blue. Perennial streams, which are portrayed on these


                                                      IV - 3








            maps with solid blue lines, must also be included in mapping tributary streams because
            their flow of water is constantly connected to the larger rivers. Intermittent streams, which
            are shown as broken blue lines, are only sporadically connected by water flow to tributary
            streams, so they were not delineated.

                  In mapping tributary streams, consideration was given to the presence of drainage
            and navigation canals that are linked to the regional watershed system. Typically, such
            canals are indicated on USGS maps in the same manner that tributary streams are
            indicated. However, drainage and navigation canals are generally the results of human
            intervention into the drainage system and tend to follow rather obvious straight or angular
            paths.

                  In addition, it is important to note that certain tributary streams and
            drainage/navigation canals were shown on USGS maps in purple, rather than the standard
            blue color. As discussed earlier, the purple color indicates features that have been added
            or revised on more recent quad maps. Therefore, these purple water features were
            mapped, along with the more prevalent blue water features, during the environmental
            inventory process.

                  2.   Tidal Shores. Tidal shores are defined in the Criteria Regulations as the land
            contiguous to a tidal body of water between the mean low water level and the mean high
            water level. In Hampton, portions of the major rivers and their tributaries are tidally
            influenced, which simplified identification. All tidal lands immediately adjacent to the Bay
            were included in the tidal shore designation, in addition to the tidal shores of the
            Hampton, Back, Newmarket, and Harris Rivers. In addition, almost all the streams that
            feed into the tidal portions of the rivers mentioned, and those smaller tidal rivers and
            inlets not mentioned, have significant lengths of tidal shores.

                  The process of mapping tidal shores began with information provided on USGS
            topographic quadrangle maps, which give a general depiction of rivers and their tributary
            streams.


                  Navigation maps from the National Oceanic and Atmospheric Administration
            (NOAA), portray the area between the high water line and the low water line, which
            constitutes the tidal shore. These maps aided in the depiction of tidal shores.

                  USGS topographic/bathymetric quadrangle maps were also utilized. These maps
            depict depth contours (isobaths) at 1-meter intervals to show the land beneath bodies of
            water. The increased level of shoreline detail shown on these maps was also useful in the
            delineation of tidal shores.





                                                        IV - 4








                  Since the upper reaches of some of the tributary streams were nontidal, these areas
             had to be examined in more detail. Useful information was obtained from NWI maps,
             which are published by the U.S. Fish and Wildlife Service. The presence of tidal wetlands
             along a tributary stream is a strong indicator of the probably existence of tidal flows.
             Local navigational data and related data on tidal ranges can also be used to determine
             tidal influence.

                           I
                  Additional information on the extent of        tidal flows necessary for tidal shore
             designation was secured from the Virginia Institute of Marine Sciences (VIMS), the U.S.
             Army Corps of Engineers, and the U.S. Fish and Wildlife Service, as well as from other
             public and private maritime organizations and clubs.

                  Field checking was conducted to fill data gaps and insure consistency throughout the
             City.

                       3.    Wetlands. The mapping of wetlands was perhaps the most lengthy and
             important task in the designation of CBPAs. Resources that were used in mapping
             wetlands included the NWI maps and USGS topographic maps. Of these, the NWI maps
             were the most significant resource for local Preservation Area designation. NWI maps are
             normally most effective when used in conjunction with the other resources, especially
             hydric soils data from soil surveys. Unfortunately there is no Soil Survey for the City of
             Hampton, therefore, hydric soils were determined in the field. Another mapping resource
             that was useful in identifying wetlands is color aerial photography. Such photography was
             secured from the Norfolk District, Corps of Engineers.

                  In the paragraphs below, procedures for identifying and mapping wetlands are
             described based on the Federal Manual for Identifting and Delineating Jurisdictional
             Wetlands (1989). The mapping of wetlands was accomplished in general accordance with
             the procedures outlined in the Federal Manual. This procedure centered on the use of
             NWI maps, backed up by other mapping resources. Areas where the NWI data was
             supported by data from other resources was identified on working maps and checked
             against aerial photographs, or field verified. Field verification was applied more frequently
             in non-tidal isolated wetlands as these areas were difficult to distinguish from upland areas.

                  It should be noted that although the NWI for Tidewater is criticized for a high
             degree of inaccuracy, inaccuracies are primarily the result of the scale of the map.
             Problems arise when NWI maps are used for regulatory programs. It is not the intent of
             the NWI maps to provide detailed wetland information for regulatory matters, i.e., Section
             404 Permits. For the purposes of delineating CBPAs and generally establishing a planning
             information base, NWI maps were a useful and important tool. Delineation of detailed




                                                         IV - 5








            boundaries of wetlands or other components of Preservation Areas for regulatory purposes
            should ordinarily be determined on a site-specific basis by an applicant prior to site plan
            review.


                  NWI maps are produced by the U.S. Fish and Wildlife Service as part of their
            systematic effort to classify and map America's remaining wetlands. In most cases, photo-
            interpretation of color-infrared photographs was combined with an examination of existing
            information and field verification by Fish and Wildlife Service biologists to produce
            inventory maps. NWI maps are able to show wetlands as small as 1/10 of an acre.
            However, in preparing NWI maps, the Fish and Wildlife Service used aerial photo imagery
            that is variable in scale and in resolution. Wetlands without a very distinct "signature" on
            an aerial photograph may not be mapped unless they are greater than one acre in size.

                  The procedure for identifying and mapping wetlands is described in detail in the
            Federal Manual for Identifying and Delineating Jurisdictional Wetlands. This manual was
            published in 1989 as a cooperative effort by several federal agencies: the U.S. Army
            Corps of Engineers, the U.S. Environmental Protection Agency, the U.S. Fish and Wildlife
            Service, and the U.S.D.A. Soil Conservation Service. The federal manual serves as the
            technical basis for recognizing and defining wetlands which are jurisdictional, that is,
            regulated by federal law.

                  C. DESIGNATION


                       1.    Resource Protection Areas (RPAs). The Regulations establish the RPA
            as the shoreward component of the Chesapeake Bay Preservation Area. Lands that were
            included in the RPA designation include the following:

                                  Tidal wetlands


                                  Nontidal wetlands connected by surface flow and contiguous to tidal
                                  wetlands or tributary streams

                                  Tidal shores


                                  Tributary streams

                                  A buffer area not less than 100 feet in width landward of all other
                                  components of RPAs and along both sides of any tributary stream

                  In their natural state, the RPA components provide intrinsic water quality benefits,
            including the protection of physical, biological, ecological, and chemical processes which
            trap, convert, and assimilate nutrients, runoff, toxics, and sediment. Ironically, these same


                                                        IV - 6








            functions make the RPA components especially susceptible to pollution. Excess nutrients,
            sediment, runoff, toxics, and other adverse effects of human activities overload these areas,
            impairing their short-and long-term ability to function properly. and to minimize these
            same impacts on state waters and aquatic resources.

                  These areas, which are generally closest to the water, are also the most sensitive
            components of CBPAs. Therefore, RPAs were carefully defined to ensure that these areas
            are included in the local designation process and protected. The regulations require these
            areas, as a minimum, to be mapped and designated as RPAs. Within RPAs, land uses
            and developments are to be closely regulated. Generally, development is limited to water
            dependent facilities and redevelopment of existing structures.

                  Once the components of the RPA were delineated, a buffer area was designated.
            The buffer is an area not less than 100 feet wide, located next to, and landward of, the
            other RPA components and along both sides of any tributary stream.

                  The RPA designation criteria, coupled with readily available data and mapping
            resources for most of those components, provided a rather direct, logical method for
            designating RPAs. These components tended to be adjacent to each other, following the
            stream pattern.

                       2.   Resource Management Areas (RMAs). The Regulations establish the
            RMAs as the landward component of Chesapeake Bay Preservation Areas. Lands that
            were considered for designation as RMAs include the following:

                                  Nontidal wetlands


                                  Floodplains

                                  Highly erodible soils

                                  Highly permeable soils

                                  Other lands at local discretion



                  RMAs are important in terms of water quality primarily because, if improperly used
            or developed, they could release- significant amounts of nonpoint source pollutants into the
            surface and ground water systems. The Regulations do not limit the types of land use and
            development that may occur within the RNIA. Instead, a variety of performance criteria
            will be applied to any use or development within RMAs to ensure that those land
            disturbances that do occur will minimize the adverse impact on water quality.


                                                       IV - 7








                 Unlike the delineation of RPAs, which must closely adhere to the Regulations, was
            the designation of RMAs was left in large part to the City. The delineation of RPAs
            followed the natural boundaries of the land features themselves.           By contrast, the
            geographic extent of RMAs were determined by the City according to the analysis of
            components of RMAs and an examination of local conditions. The features mentioned
            earlier are land forms which were considered for inclusion within the RMA boundary. For
            example, a locality may choose not to designate certain isolated nontidal wetlands which
              ay not have a direct impact on the water quality of the Bay and its tributaries. At the
            same time, the lands that may be designated as part of the RMA are not limited to those
            M

            components mentioned here. A locality may choose to include, as part of the RMA,
            certain other lands which, for example, serve as groundwater recharge areas.

                 For the City of Hampton, the designation of the RMA consists of the 100-year
            floodplain or a distance of 500 feet from the RPA in the southern portion of the City,
            whichever is greater. Additionally, Brick Kiln Creek, Salt Ponds and most of the northern
            Back River drainage basins are designated as RMAs. These areas were singled out
            because they ultimately drain into Chesapeake Bay and are sensitive to increases in
            stormwater runoff.


                       3.   Determining the Geographic Extent of the RMA While localities have
            broad authority in the designation of Resource Management Area and may choose among
            several options, it is essential to utilize the environmental inventory as a basis for that
            determination. In the final analysis, the designation must be legally defensible and based
            upon water quality protection, consistent with the Act, the Criteria Regulations, and other
            police powers specifically granted under Title 15.1 of the Code of Virginia.

                       4.   Intensely Developed Areas (IDAs). The designation of Intensely Developed
            Areas (IDAs) was intended to address the unique land use patterns and water quality
            impacts of heavily urbanized areas. Such areas are characterized by industrial, commercial,
            residential, and institutional uses which are spatially concentrated, heavily trafficked, and
            largely devoid of natural vegetation. Examples of these areas generally include downtown
            Hampton, Phoebus, Mercury Central, and Buckroe. Development within these areas is
            usually confined to either redevelopment of previously developed sites or construction on
            small, vacant or "infill" parcels. The concentration of intensive uses and the prevalence
            of impervious surfaces in these areas contribute a variety of nonpoint source pollutants,
            such as hydrocarbons and heavy metals, to surface waters.

                       5.   Delineating IDAs.      Delineation of IDAs was the final stage in the
            designation of CBPAs. Following the delineation of RPAs and RMAs, Hampton officials
            examined the pattern of land uses within Preservation Areas. The analysis focused on
            present conditions, as opposed to projected trends. For example, the IDA boundary was
            not used to define the geographic extent of an "urban growth area" to be built over time.


                                                       IV - 8








             Instead, designation of IDAs involved the consideration of concentrations of existing
             development and infill areas for a one-time delineation as an overlay to CBPAs.

                  The Regulations established two basic conditions which must characterize any area
             to be designated as an IDA. Section 3.4 of the Regulations states:

                  "Areas of existing development and infill sites where little of the natural environment
                  remains may be designated as Intensely Developed Areas."

                  This condition was the over-riding test before any area within the City was delineated
             as an IDA.      In addition to this central requirement, IDA designation was further
             contingent upon the characteristics of an area meeting any one of the following three
             conditions:


                       Development has severely altered the natural state of the area such that it has
                       more than 50% impervious surface;

                       Public sewer and water is constructed and currently serves the area by the
                       effective date of the Regulations (October 1, 1989). This condition does not
                       include areas planned for public sewer and water;

                       Housing density is greater than or equal to four dwelling units per acre.

                  Delineating the boundaries of the IDA involved examining the land use pattern
             within CBPAs to determine where the above conditions were present. Hampton officials
             began by locating concentrations of high density development. Potential IDAs were
             reviewed in relation to the comprehensive plan, particularly where the plan identifies
             redevelopment areas. The criteria outlined above was then applied to determine eligibility
             for IDA status. The IDA boundaries were drawn so as to bypass larger, naturally
             vegetated areas. At the same time, the designation process did not isolate small, individual
             sites as IDAs; rather, IDAs were intended to serve as areas where future redevelopment
             activity is focused.














                                                        IV - 9









          V. CHMAPEAXE BAY PRESERVAnON AREA OVERLAY DISTRICr MAPS

          NOTE: Due to the mapping limitations related to scale and size of the drawings (11 x
                   17"), it was deemed impractical to include these in the report. Full size maps
                   (24 x 36") are on display and can be reviewed at the City of Hampton Planning
                   and Zoning Department.









            vi. LrrEkATuRE CITED


            Barnard, Thomas A. Jr., and G. M. Silberhorn. 71dal Marsh Inventory, City of Hampton,
            VA Special Report No. 60 in Applied Marine Science and Ocean Engineeting. Virginia
            Institute of Marine Science Gloucester Point Virginia.

            Commonwealth of Virginia, Chesapeake Bay Local Assistance Department. Local
            Assistance ManuaL November', 1989.

            Conservation Foundation, Protecting America's Wetlands. Waldorf, MD: Harper Graphics,
            1988.


            Hershner, Carl. "What is a Wetland?", Presentation during Wetlands Workshop,
            Henricopolis Soil and Water Conservation District, Henrico County, VA. April 13, 1989.

            Thurow, Charles, W. Toner & D. Erley, Performance Controls for Sensitive Lands
            (Washington, D.C.: Planning Advisory Service Report Nos. 307, 308; 1975).

            Rice, Barbara, ed, Conserving Our Wedand Resources Avenues for Ciazen Participation.
            Richmond, VA: Chesapeake Bay Foundation, 1987.

            Federal Interagency Committee for Wetland Delineation. 1989. Federal Manual for
            Idenu]f*g and Delineating Jufisdictional Wetlands. U.S. Army Corps of Engineers, U.S.
            Environmental Protection Agency, U.S. Fish and Wildlife Service, and U.S. D. A. Soil
            Conservation Service, Washington, D.C., Cooperative Technical Publication.

            U.S. Department of the Interior, Fish and Wildlife Service. Class#widon of Wetlands and
            Deepwater Habitats of the United States. Washington, D.C.: U.S. Fish and Wildlife Service,
            1979.


NOAA COASTAL SERVICES CENTER LIBRARY

3 6668 14102 6197