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                           SOUTHWEST ESCAMBIA COUNTY
                         STORMWATER MANAGEMENT PLAK/

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                    FOR ESCAMBIA COUNTY WITH FINANCIAL ASSISTANCE FROM

                    THE FLORIDA DEPARTMENT OF ENVIRONMENTAL REGULATION

                       AND THE COASTAL ZONE MANAGEMENT ACT OF 1972

                                          K:

                                           PREPARED BY

                                                              BASWERVILLE
             BARRETT DAFFIN AND CARLAN, INC.                  DONOVAN
                         AkCllJTEC-l*S ENGINEERS PLANNERN
                                                       0 ENGINEERS, WC.

                                          TABLE OF CONTENTS

                  SECTION                         TITLE                          PAGE

                  1.0           INTRODUCTION

                                      PROJECT HISTORY                            1-1

                  1.2                 STUDY AREA DESCRIPTION                     1-3

                  1.3                 STUDY OBJECTIVES                           1-8

                  1.4                 SCOPE OF REPORT                            1-10

                  2.0           INVENTORY                                        2-1

                  2.1                 BASE MAP PREPARATION                       2-1

                  .2.2                DRAINAGE STRUCTURE SURVEY                  2-2

                  2.3                 BASIN DELINEATION                          2-8

                  2.4                 TOPOGRAPHY                                 2-10

                  2.5                 HYDROLOGIC DATA COLLECTION
                                      & REVIEW OF RELEVANT STUDIES               2-12

                  2.6                 SOILS                                      2-18

                  2.7                 LAND USE                                   2-22

                        2,7*1         EXISTING LAND USE,
                        2.7.2         FUTURE LAND USE                            2-24

                  2.8                 FLOOD MAP                                  2-26

                  3.0           PROBLEM AREA IDENTIFICATION                      3-1

                  3.1                 SOURCES OF INFORMATION                     3-1

                  3.2                 PUBLIC MEETING                             3-2

                  3.3                 PROBLEMS IDENTIFIED                        3-3

                                             TABLE OF CONTENTS

                    SECTION                          TITLE                           PAGE

                    4.0           FUNDING OF   STORMWATER   MANAGEMENT               4-1

                    4.1                 SPECIAL ASSESSMENT                           4-1

                    4.2                 AD VA LOREM TAX INCREASES                    4-6

                    4.3                 GRANTS                                       4-8

                    4.4                 DEVELOPMENT IMPACT FEES                      4-10.

                    4.5                 STORMWATER AS A UTILITY                      4-12

                    4.6                 CONCLUSION                                   4-14

                    5.0           PROBLEM DESCRIPTIONS AND STRUCTURAL
                                  ALTERNATIVES EVALUATED                             5-1

                    5.1                 BRIDGE CREEK BASIN                           5-1

                    5.2                 BAYOU GRANDE HEADWATERS AND
                                        BAYOU GRANDE    BASIN                        5-23

                         5.2.1          BAYOU GRANDE HEADWATERS        NORTH         5-24
                         5.2.2          PLEASANT GROVE                               5-30

                    5.3                 GULF BEACH HIGHWAY                           5-48

                         5.3.1          GRAND LAGOON SUBDIVISION                     5-49
                         5*3*2          SEAGLADES AREA                               5-@O
                     -   5.3.3          QUINAVISTA AREA                              5-65
                         5.3.4          TREASURE HILL                                5-69

                    5.4                 PERDIDO BAY RESORT AREA                      5-74

                         5.4.1          DOUG FORD DRIVE                              5-74
                         5.4.2          ARAPAHO DRIVE                                5-80
                         5.4.3          ZUNI CIRCLE                                  5-83

                    5.5                 PENSACOLA BEACH                              5-84

                         5.5.1          FT. PICKENS ROAD                             5-85
                         5.5.2          ENSENADA UNO                                 5-88

                    5.6                 JONES SWAMP & GARCON SWAMP BASINS            5-94

                                          TABLE OF CONTENTS

                  SECTION                        TITLE                          PAGE

                  5.7                 PARADISE BEACH                            5-95

                  5.8                 BRONSON FIELD BASIN                       5-95

                  5.9                 PERDIDO KEY/INNERARITY AREA               5-96

                        5.9.1         PERDIDO KEY                               5-96
                        5.9.2         INNERARITY PENINSULA                      5-98

                  5.10                TARKILN BAY                               5-99

                  5.11                SANDY CREEK/WEEKLEY BAYOU BAS.IN          5-99

                  6.0           NON-STRUCTURAL RECOMMENDATIONS                  6-1

                  6.1                 GENERAL RECOMMENDATIONS                   6-1

                  6.2                 SPECIFIC RECOMMENDATIONS
                                      FOR SELECTED AREAS                        6-9

                                           LIST OF FIGURES

                  FIGURE                         TITLE                          PAGE

                  1-1                 STUDY AREA                                1-5

                  1-2                 SANTA ROSA ISLAND STUDY AREA              1-6

                  2-1                 DRAINAGE STRUCTURE INVENTORY              2-3

                  2-2                 MAJOR BASINS                              2-27

                  2-3                 TOPOGRAPHIC FEATURES &
                                      LOW LYING AREAS                           2-28

                  2-4                 SOILS MAP                                 2-29

                  2-5                 EXISTING LAND USE                         2-30

                  2-6                 FUTURE LAND USE                           2-31

                  2-7                 FLOOD MAP                                 2-32

                  3-1                 DRAINAGE PROBLEM AREAS                    3-10

                  3-2                 SANTA ROSA ISLAND PROBLEM AREAS           3-11

                  .5-1                DRAINAGE ALTERNATE NO. 1
                                      BRIDGE CREEK BASIN                        5-14

                  5-2                 DRAINAGE ALTERNATE   NO. 2
                                      BRIDGE CREEK BASIN                        5-15

                  5-3                 DRAINAGE ALTERNATE   NO. 1
                                      BAYOU GRANDE HEADWATERS NORTH             5-15

                  5-4                 DRAINAGE ALTERNATE NO. 2
                                      BAYOU GRANDE HEADWATERS NORTH             5-36

                  5-5                 DRAINAGE ALTERNATE NO. 1
                                      PLEASANT GROVE                            5-41

                  5-6                 DRAINAGE ALTERNATE NO. 2
                                      PLEASANT GROVE                            5-42

                  5-7                 GRAND LAGOON ALTERNATE NO. 1              5-56

                  5-8                 SEAGLADES ALTERNATIVE                     5-63

                                           LIST OF FIGURES

                  FIGURE                        TITLE                           PAGE

                  5-9                QUINAVISTA ALTERNATIVE                     5-67

                  5-10               TREASURE HILLS ALTERNATIVE                 5-72

                  5-11               DOUG FORD ALTERNATIVE                      5-77

                  5-12               DRAINAGE ALTERNATIVE NO. 1
                                     FT. PICKENS ROAD                           5-92

                  5-13               DRAINAGE ALTERNATIVE NO. 2
                                     FT. PICKENS ROAD                           5-93

                                            LIST OF TABLES

                  TABLE                         TITLE                          PAGE

                  2-1                WETLANDS ANALYSIS                         2-11

                  2-2                SOILS ANALYSIS                            2-21

                  3-1                DRAINAGE PROBLEM AREAS                    3-5

                  4-1                ALTERNATIVE COSTS                         4-5

                  5-1                BRIDGE CREEK BASIN
                                           COST ESTIMATE-ALTERNATE NO. 1       5-16

                  5-2                BRIDGE CREEK BASIN
                                           COST ESTIMATE-ALTERNATE NO. 2       5-19

                  5-3                ALTERNATIVE EVALUATION FOR THE
                                           BRIDGE CREEK BASIN                  5-22

                  5-4                COST  ESTIMATE ALTERNATIVE NO. 1
                                           BAYOU GRANDE HEADWATERS AND,
                                           BAYOU GRANDE BASIN                  5-37

                  5-5                COST  ESTIMATE ALTERNATIVE NO. 2
                                           BAYOU GRANDE HEADWATERS -
                                           NORTH                               5-39

                  5-6                ALTERNATIVE EVALUATIONS
                                           BAYOU GRANDE HEADWATERS -
                                           NORTH                               5-40

                  5-7                COST  ESTIMATE ALTERNATIVE NO. 1
                                           BAYOU GRANDE HEADWATERS
                                           AND BAYOU GRANDE BASIN              5-43

                  5-8                ALTERNATIVE EVALUATION
                                           PLEASANT GROVE                      5-47

                  5-9                COST ESTIMATE ALTERNATIVE NO. 1
                                           GRAND LAGOON                        5-57

                  5-10               COST ESTIMATE ALTERNATIVE NO. 2
                                           GRAND LAGOON                        5-58

                  5-11               ALTERNATIVE EVALUATIONS
                                           GRANDE LAGOON SUBDIVISION           5-59

                                            LIST  OF TABLES

                  TABLE                           TITLE                         PAGE

                  5-12                COST ESTIMATE -  SEAGLADES AREA.          5-64

                  5-13                COST ESTIMATE -  QUINA VISTA AREA         5-68

                  5-14                COST ESTIMATE -  TREASURE HILL            5-73

                  5-15                COST ESTIMATE -  DOUG FORD DRIVE          5-78

                  5-16                COST ESTIMATE -  WEST END
                                           DOUG FORD DRIVE                      5-79

                  5-17                COST ESTIMATE ARAPAHO DRIVE               5-82

                  .5-18               COST ESTIMATE ALTERNATIVE NO. 1
                                           FT. PICKENS ROAD                     5-89

                  5-19                COST ESTIMATE ALTERNATIVE NO. 2
                                           FT. PICKENS ROAD                     5-90

                  5-20                ALTERNATIVE EVALUATION
                                           FT. PICKENS ROAD                     5-91

                                           LIST OF EXHIBITS

                   EXHIBIT                       TITLE                          PAGE

                   2-1 & 2-2          INFORMATION REQUIRED               2-5    2-6
                                      BRIDGE SURVEYS

                   2-3                DIAGRAM SHOWING INFORMATION
                                      REQUIRED FOR BRIDGE
                                      SURVEY                                    2-7

                   3-1                DRAINAGE STUDY QUESTIONNAIRE              3-4

                   4-1                LETTER FROM DER                         4-16

                   4-2                LETTER FROM DEPARTMENT OF               4-17
                                      COMMUNITY SERVICES

                   5-1   5-2          PROCEDURE FOR THE EVALUATION
                                      OF STRUCTURAL ALTERNATIVES         5-2 & 5-3

                   6-1                CURRENT DER CRITERIA FOR
                                      WET DETENTION SYSTEMS                   6-13

                   6-2                PLANT SPECIES SUITABLE AND
                                      SOMETIMES AVAILABLE FROM
                                      NURSERIES FOR LITTORAL ZONE
                                      PLANTINGS OF DETENTION PONDS            6-16

                                          1.0 INTRODUCTION

                  1.1 PROJECT HISTORY

                  Southwest Escambia County has a natural environment composed

                  of coastal dunes, wetlands, bay and salt water marshes bor-

                  dered by beautiful white sand beaches. The area is

                  currently sparsely developed, but is already experiencing

                  development pressures, particularly for residential com-

                  munities.

                  In 1972, the U. S. Congress passed the Coastal Zone

                  Management Act, which provided funding assistance to coastal

                  states, in order that coastal resource management plans

                  could be developed.

                  In 1985, the Escambia/Santa Rosa Coast Resource Management

                  Committee adopted a Resource Management Plan for Escambia

                  and Santa Rosa Counties. In that plan, recommendations were

                  made that local governments adopt comprehensive stormwater

                  management plans to address the quantity and quality of

                  stormwater runoff in their jurisdictions. Escambia County

                  has divided the coastal zone into study regions, the study

                  area addressed in this report, being one of several of these

                  regions.

                 Honce, this study is funded in part by Escambia County along

                 with federal funds made available under the Coastal Zone

                 Management Act of 1972. This money was made avail able

                 through the Florida Department of Environmental Regulations

                 Office of Coastal Management.

                 Escambia County contracted with Barrett Daffin and Carlan,

                 Inc. and Baskerville-Donovan Engineers, Inc., a Joint

                 Venture, to prepare a stormwater Master Plan for the study

                 area. The fully executed agreement was received by the

                 Joint Venture on June 1, 1987, and work on the project pro-

                 ceeded shortly thereafter.

                 On July 7, 1987, the Board of County Commissioners voted to

                 amend the Contract to include revisions required by the

                 office of Coastal Management of the Department of

                 Environmental Regulation of the State of Florida. These

                 modifications were necessary for the receipt of grant funds.

                 The Joint Venture submitted a proposal to.the County to

                 delete the development of a computer model for the study

                 area and to instead develop more detailed alternatives for

                 selected locations within the study area. This proposal was

                 approved by the Commission on October 20, 1987.

                 A public meeting was held on November 17, 1987 to report

                 study findings and to solicit public input regarding

                                            1-2

                drainage problems and their solutions. Questionnaires were

                distributed to those citizens in attendance so that further

                study data could be obtained.

                There will be another public hearing at a regularly sche-

                duled meeting of the Escambia County Board of County

                Commissioners prior to adoption of the final report recom-

                mendations.

                1. 2 STUDY AREA DESCRIPTION

                A portion of the study area is shown on Figure 1-1. The

                area is bounded on thenorth by U. S. 98, on the east by

                Fairfield Drive (S.R. 727), on the south by the Gulf of

                Mexico and on the west by the Alabama-Florida state line.

                The remainder of the study area is shown on Figure 1-2.

                This area includes that portion of Santa Rosa Island lying

                between the Gulf Islands National Seashore and Fort Pickens,

                known as Pensacola Beach.

                The study area is bounded by or includes several significant

                water bodies. On the east, there is Bayou Grande, on the

                north, Perdido Bay, on the west Tarkiln Bay and Perdido Bay

                and on the south, the Big Lagoon and the Gulf of Mexico.

                These waterbodies are rated as Class III waters as defined

                in Section 17.309 of the Florida Administrative Code.

                                            1-3

                 There are several creeks within the study area, those being

                 Jones Creek in thenortheast, Bridge Creek in the north

                 central and Sandy Creek in the west central portion of the

                 study area.

                 Two large named swamps, Jones and Garcon, comprise parts of

                 the study area. A small portion of Jones Swamp is located

                 in the northeast corner and Garcon Swamp is located entirely

                 within the south central section. Garcon Swamp's east-west

                 dimension spans almost the entire area, while most of Jones

                 Swamp is located east of the study area.

                 There are numerous other low lying areas that are unnamed.

                 In fact, north of old Gulf Beach Highway (C.R. 297) and east

                 of Bauer Field Road (C.R. 293), over twenty (20) percent of

                 the land area is comprised of.areas that would be classified

                 as swamp.

                 This large percentage is due to the great expanse of almost

                 level terrain. With the exception of those areas imme-

                 diately adjacent to the coastlines or bayous, the elevation

                 range for the entire area is from around fifteen (15)

                 f.m.s.l. to about thirty-three (33) f.m.s.l.

                 Due to the flat terrain, rather impermeable soil formations

                 have developed over most of the area, that support a seaso-

                 nally high water table to within one (1) to two (2) feet of

                                             1-4

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                                                     STUDY AREA BOUNDARY
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                                .---SANTA ROSA                                               ESCAMBIA COUNTY LINE

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                the surface. This  condition compounds stormwater runoff

                problems in the area.,

                Major transportation.routes within the area have been placed

               .on fill sections ranging from two to six feet above natural

                grade. This allows positive drainage of the roadways and

                protects the pavement structure from high water tables

                encountered. The major routes in the area are:

                    1)   Fairfield Drive (S R. 797)

                         North-South route forms the eastern boundary of the
                         study area.

                    2)   U.S. 98 (S.R. 30).

                         East-West route forms the western boundary of the
                         study area.

                    3)   Blue Angel Parkway (S R. 173)

                         North-South route located in the eastern part of
                         the study area.

                    4)   Sorrento Road (S.R. 292)
                         (Now Gulf Beach Highway)

                         East-West route located in the central part of t1le
                         study area.

                    5)   Dog Track Road (C.R. 297)

                         North-South route located in the central part of
                         the study area.

                    6)   Bauer Field Road (C.R. 293)

                         Noxth-South route located in the western part of
                         the study area.

                                            1-7

                     7)   Old Gulf Beach Highway (C.R. 297)

                          East-West route that runs along coastal area south
                          of Garcon Swamp.

                 With the exception of Old Gulf Beach Hiqhway, all of the

                 roadways have been@ constructed within the last ten (10),

                 years and their construction has significantly impacted

                 development.in the-area.

                 On Pensacola Beach, the major roadways are the Ft. Pickens

                 Road and Via DeLuna Drive. These roadways head west and

                 east respectively shortly after crossing over   the bridge

                 adjoining Pensacola Beach and the peninsula at Gulf Breeze,

                 Florida.

                 1.3 STUDY OBJECTIVES

                 The primary objectives in the study were to develop alter-

                 native stormwater management plans for the study area and

                 evaluate each alternative based on technical, economic,
                                                                             A
                 environmental, and social impacts associated with each.

                 Based on evaluation of these alternatives, an optimum storm-

                 water management plan is recommended for each of the twelve

                 basins.

                 The second objective was to evaluate funding for implemen-

                 tation of the selected alternatives(s). The various funding

                 sources considered were grants, special assessments, utility

                                              1-8

                charges, ad valorem taxation, and impact fees.

                Third, non-structural regulatory measures were investigated

                and recommendations made concerning future development in

                the area.

                Another objective was to develop a tool useful to Escambia

                County that guide s planners and engineers in making informed

                decisions regarding development in the area. Specifically,

                problem areas have been identified and observations made

                regarding ways to avoid the occurrence of similarproblems

                in the future.

                The final objective was to develop an implementation sche-

                dule for the selected alternative based on priority and

                funding availability.

                The objectives are addressed in this report at a level of

                detail commensurate with the limited timeframe and money

                appropriated to the task. Therefore, in some instances, A

                is recommended that more detailed studies be undertaken

                prior to implementation of certain elements in the plan.

                These recommendations are made only when implementation of

                the plan element.is impossible or risky with the amount of

                information-available.

                                            1-9

                 1.4 SCOPE OF REPORT

                 Generalized solution concepts are considered for the problem

                 areas in each basin. Due to time constraints, these solu-

                 tions will only be approximate solutions and-structure sizes

                 used are based on calculations using methods suitable for

                 approximating flows and volumes. Detailed solutions and the

                 exact locations of drainage facilities will be determined in

                 the design phases following the adoption of this report.

                 It is not the intent of this report to lock-in on solutions

                 based on factors such as parcel divisions, and solutions

                 presented graphically do not consider the location of pro-

                 perty lines or ownership. It is assumed that modifications

                 to alignment will be necessary to implement some solutions

                 and that these details will be addressed in the design and

                 preparation of plans for these facilities.

                 Therefore, this report will introduce various solution con-

                 cepts and the approximate cost to implement each solution.

                 The alternatives presented, unless otherwise stated, pro-

                 vide a level of service for all storms up to and including

                 a 25 year   24 hour storm.

                 In analyzing funding sources, each source is discussed and

                 pro and cons of each method are presented.  No detailed ana-

                 lysis is presented for every funding mechanism. Based on

                                             1-10

                approximate methods, each funding mechanism will be eva-

                luated as a revenue source and compared to th e capital

                requirements for the selected stormwater management.plan.

                                       2.0 INVENTORY,

                2.1 BA SE MAP PREPARATION

                Base maps for the study area were prepared utilizing

                U.S.G.S. quadrangle maps and aerial photographic maps. Most

                of the topographic information was taken from the quadrangle

                maps, including lakes, inlets, bayous, and streams. Some

                roadway information was also taken from those maps; however,

                this information was limited, due to the age of the aerials

                from which the quadrangle maps were prepared.

                After the base map was prepared, roadways, streets, lakes,

                ditches, and retention areas were added to the base through

                review of recent aerials. Street locations and names were

                taken from the latest wall maps prepared by Champion

                Corporation. However, after reviewing aerials flown in

                November of 1986, it was apparent that some of the streets

                shown were platted streets only and had not, as yet, been

                constructed. In other cases, some streets not shown had

                been constructed. Therefore; those recently constructed

                streets were added to the base map, while not yet

                constructed streets we re removed.

                In some instances, street names have changed several times

                in the past few years. The most recent names were used on

                                            2-1

                the maps, as indicated  on the latest sources containing

                street names.

                Some verification of the information contained on the base

                maps by field observation was completed. However, not every

                street name or location was field verified.

                2.2 DRAINAGE STRUCTURE SURVEY

                An inventory of existing drainage structures along the major

                transportation routes was conducted to aid in problem iden-

                tification and drainage basin delineation.

                Along these major routes, drainage structures were iden-

                tified and surveys conducted of the major structures along

                each roadway. These structures are shown on Figure 2-1.

                In some places, culverts are indicated, with no size shown.

                In these locations, culverts exist, but due to inac-

                cessibility their size was not determined. For instance,

                along Blue Angel Parkway, at the time reconnaissance was

                made., water stood above the tops of the culverts on both

                sides of the roadway, for more than half of the culverts

                along the parkway. This was not flowing water, but standing

                water. The culverts do not have a positive outlet at their

                constructed elevation. In any case, all of these culverts

                are expected to be thirty (30) inches in diameter.or less

                                             2-2

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                and possess no real significance  at this time since they

                have no ability to transport stormwater.

                Major culvert and bridge locations were surveyed in detail,.

                including upstream, downstream, and roadway sections in

                accordance with the guidelines on Exhibits 2-1 thru 2-3 for

                bridge surv eys. These guidelines.were developed to obtain

                infomation useful in the hydraulic analysis of bridges in a

                format compatible with several co mmercial computer  programs

                that assist in performing the analysis.

                In all, ten (10) culvert or bridge locations were selected

                for detailed survey. Analysis of these structures indicates

                that few,of them significantly restrict flow out of their

                respective basins, and that stricter controls exist at other

                points within the contributing basin(s). However, two

                structures may require future consideration, one being the

                bridge on old Gulf Beach Highway where it crosses Bayou

                Grande. The other is the 10' X 10' box culvert under Bauer

                Field Road at the Sandy Creek crossing. This structure is

                large enough, but due to water standing to half the height

                of the culvert, the effective area for conveying stormwater

                is significantly reduced. A wider structure may be required

                at this location at some point in the future.   A new bridge

                on Old Gulf Beach Highway is not an immediate concern, but

                the bridge immediately upstream on Blue Angel Parkway has

                                             2-4

                                                       :;D
                                    INFORMATIO]
                                       BRIDGE SURVEYS

                1. Determine opening dimensions A, B, C, D (See attached

                    sketch).

                2.  Determine bridge pier width - T (Attached sketch) as

                    closely as possible   determine pier shape by selecting

                    appropriate shape from following list:

                                         Semi-circular nose & tail

                                         Twin cylinder piers with connecting
                                        diaphragm

                                         Twin cylinder piers without
                                        diaphragm

                                         Square nose & tail

                3. Determine abutment side constriction lengths - LAR and

                    LAL-

                4.  Determine the elevation of the bridge low chord on the

                    upstream side of the bridge - ELLC (attached sketch).

                5. Take cross sections at  locations one through five as

                    shown on the attached sketch:

                    (1) Section one should be located approximately four

                         times the length of the greater of the left or

                                                                 EXHIBIT 2-1

                          .right abutment constriction length as determined in

                          Step 3 above.

                     (2)  Section two should be located at the  immediate

                          downstream face of the bridge.

                     (3)  Section three should be a roadway profile (normally

                          centerline) if the roadway is super-elevated, shoot

                          the high edge of the roadway. If a curb or barrier

                          wall is adjacent to the upstream edge of the

                          bridge, shoot the top of curb or wall elevation

                          (ETHW) along the bridge span. Pick up roadway pro-

                          file at each end of bridge. The roadway profile

                          should extend each direction away from the bridge

                          until the roadway elevation is 2 to 3 feet above

                          the low point on the profile in the vicinity of the

                          bridge.

                     (4)  Cross section four is located a distance upstream.,

                          from section two a distance equal to the bridge

                          with (W, on attached sketch).

                     (5) Cross section five should be located approximately

                          a distance equal to the bridge opening A + B + C +

                          D upstream of section four. (L5 on attached

                          sketch).

                                                                   EXHIBIT 2-2

                       0-71

          40
                               f IIILC@@-

           DIAGRAM SHOWING INFORMATION REQUIRED FOR
                         BRIDGE. SURVEY

                significantly  greater capacity to pass stormwater prior to

                overtopping.   This could cause problems at the Old Gulf

                Beach Highway  at some point in the future. Infrastructure

                renovation for old Gulf Beach Highway is an item that will

                be addressed in the future and bridge improvements at the

                Bayou Grande crossing should be considered at that time.

                2.3 BASIN DELINEATION

                After base map preparation and drainage structure inventory,

                the task of determining the major basins in the study area

                was begun.

                The task was completed  using aerial topographic maps with a

                5' contour interval, furnished by Escambia County, and

                augmented by field investigation. These maps also have

                supplemental contours at 2.8 feet intervals. obviously, at

                this contour interval, and with the nearly level topography,

                it was difficult to determine the location of drainage     A

                divides.

                The major streams and bayous were selected as the focal

                points for basin determination and drainage areas were

                determined for each of the major basins. The major basins

                within the area were determined to be as follows:

                                             2-8

                     1)   Jones Swamp

                     2),  Bridge Creek/Herron Bayou

                     3)   Bayou Grande Headwaters

                     4)   Bayou Grande

                     5)   Sandy Creek/Weekley Bayou

                     6)   Garcon Swamp/Garcon Bayou

                     7)   Tarkiln Bayou

                 After these major drainage basins were determined, the

                 remaining areas were defined based on their geographic and

                 hydrologic relationship to each other. For instance, after

                 delineating the area contributing runoff to Garcon Swamp,

                 the coastal region south of Garcon Swamp Basin was lumped

                 into one area even though there is no common focal point for

                 the runoff from this area, as it is composed of many small

                 basins which drain under and over Old Gulf Beach Highway

                 (C.R. 297) to the Big Lagoon.

                 These areas remaining after the major basins were named are

                 as follows:

                     1)   Coastal area south of Garcon Swamp
                          (Old Gulf Beach Highway)

                     2)   Bronson Field Basin

                     3)   Paradise Beach Basin

                     4)   Perdido Key and Innerarity Island

                     5)   Pensacola Beach

                                             2-9

                All of these areas with the exception of Pensacola Beach,

                are shown  on Figure 2-2. The land  surface areas represented

                by these divisions are shown on Table 2-1, page 2-11.

                2.4 TOPOGRAPHY

                As stated previously, the topography of the study area is

                represented by moderately sloping terrain in the immediate

                vicinity of the coast lines with a broad flat,coastal plain

                toward the interior.

                This plain is characterized by flat upland reaches which

                drain to low lying swamps that possess little or no positive

                gradient. In many areas, there is very little difference in

                elevation between the low areas and the surrounding areas

                that drain to it. Consequently, when the low areas fill   up@

                during storms, there is no hydraulic gradient available to

                drain the surrounding "upland" areas. Unless substantial

                fill is placed, most land surrounding these low areas will
                                                                           A

                flood.

                There are a number of man-made and natural lakes, but none

                of any size or storage capacity that would significantly

                impact the runoff in the basins. Between Old Gulf Beach

                Highway and-the Garcon Swamp Basin, there are numerous

                depressions and wet-weather ponds that fill up during heavy

                rains and flow out through natural ravines to the highway.

                                             2-10

                                                            TABLE 2-1
                                                       WETLANDS ANALYSIS

                                                                          LOW-LYING
                                                                          OR
                                                                          SWAMPY            % LOW-LYING
                   BASIN NAME            ARE.A, Mi.       AREA, AC.       AREAS,  AC.       OR SWAMP

                   Bridge Creek/            5.920           3790              896             23.6
                   Herron Bayou

                   Bayou Grande             6.24            3990              615             15.4
                   Headwaters

                   Bayou Grande             3.94            2522                76             3.0

                   Jones Swamp              1.96            1252              .387            30.9

                   Garcon Swamp/            6.92            4426             1293             29.2,
                   Garcon Bayou

                   Sandy Creek/             3.34            2137              237             11.1
                   Weekley Bayou

                   Paradise                   .70             447               44             9.84
                   Beach

                   Tarkiln Bayou            1.60            1021              196             19.2

                   Coastal Area             5.48            3509              421             12.0
                   South of
                   Garcon Swamp

                   Perdido Key &            6.88            4402              459             10.4
                   Innerarity
                   Island

                   Pensacola                5.18            3317              209              6.3
                   Beach

                   Bronson                  2.29            1467              115              7.8

                This results in flow sheeting.over the highway in several

                locations during heavy rainfall.

                A prominent feature in the study area, due to its immense

                size and unusual shape is Garcon Swamp. This swamp is

                entirely self contained within a long narrow basin that

                feeds the swamp laterally along its entire length. The unu-

                sual characteristic is that for a swamp this size, there is

                not a significant basin at its head delivering surface

                runoff to the swamp.

                Lakes, streams, and swamps are shown on Figure 2-3. The

                approximate acreage of low lying areas within each basin is

                shown on Table 2-1. It is expected that the Garcon and

                Jones Swamp Basins would contain a considerable amount of

                swamp land, but also, relatively large percentages of the

                Bridge Creek Basin and Bayou Grande Headwaters contain swamp

                land.

                With the flat terrain and the prominence of low, wet areas,

                surface drainage of stormwater is difficult.

                2.5 HYDROLOGIC DATA COLLECTION AND REVIEW OF RELEVANT
                    STUDIES

                During the course of the study, a number of agencies were

                contacted regarding data they may have relevant to the study

                area. Unfortunately, very few historic records exist.

                                            2-12

                Out of all the  agencies contacted, very little useful data

                was assimilated. The fo  llowing agencies were contacted

                concerning information pertinent to the study area:.

                    1)   U. S. Geological Survey
                         Tallahassee, Florida

                    2)   Escambia County Engineering, Planning and Road
                         Operation Departments, Pensacola, Florida

                    3)   Florida Department of Environmental Regulation
                         Pensacola, Florida

                    4)   Northwest Florida Water Management District
                         Havana, Florida

                    5)   U. S. Army C orps of Engineers
                         Mobile District, Mobile, Alabama

                    6)   Santa Rosa Island Authority
                         Pensacola Beach, Florida

                    7)   U. S. Department of the Interior
                         U. S. Fish and Wildlife Service
                         National Wetlands Research Center
                         Slidell, Louisiana

                    8)   Florida Department  of Transportation
                         Pensacola, Florida
                         Chipley, Florida

                    9)   City of Pensacola,  Engineering Department

                    10)  West Florida Regional Planning County
                         Pensacola, Florida

                    11)  U. S. Soil Conservation Service
                         Pensacola, Florida

                The U.S.G.S. did not have any stream flow gages located

                in or in the vicinity of the study area. The closest

                available streamflow data was for Carpenter's Creek in the

                                             2-13

                 eastern part of Pensacol a. Due to the great disparity in

                 hydrology of the Carpenter's Creek basin compared to basins

                 in the study area, it is unlikely that this gage can provide

                 reliable parameters, even for a regional type analysis.

                 However, limited streamflow data was obtained in case its

                 use becomes necessary. An exhaustive search with other

                 agencies revealed no sour,ce of streamflow data.

                 The U.S.G.S. has provided groundwater data from  observation

                 wells. Although data was provided for a number  of wells in

                 the county, only two were considered applicable to the study

                 area. The U.S.G.S. also provided a highwater survey for the

                 coastal areas associated with Hurriane Frederick in 1979.

                 Escambia County personnel cooperated in providing the bulk

                 of the data collected. This included three of the studies

                .referenced previously, aerial topography at 1"=300' for the

                 entire study area., as-built roadway plans for a number of
                 ro ads in the study area and citizen complaint information"

                 from the Road Operations Division. Also, land use maps were

                 provided by the Planning Department.

                 The Florida Department of Environmental Regulation has pro-

                 vided information in the form of studies and knowledge of

                 the study area, as well as feedback regarding drainage

                 alternatives and their relationship to stormwater and

                 wetland regulations.

                                             2-14

                 The Northwest Florida Water Management District provided one
                 of the studies reviewed 'concerning groundwater.

                 The U.S. Army Corps of Engineers was contacted concerning

                 tidal data. However, they felt better information would be

                 available from the highwater survey provided by   the U.S.G.S.

                 The Santa Rosa Island Authority assisted by providing a

                 guided tour of Pensacola Beach problem areas and emphasizing

                 those areas considered critical.

                 Wetlands and Ecosystem mapping for the study area was

                 obtained from the U.S. Fish and Wildlife Service.

                 The West Florida Regional Planning Council was very coopera-

                 tive in providing maps used in the study.

                 Finally, the U.S. Soil Conservation Service provided soils

                 interpretive maps for Escambia County, useful in determining

                 what types of development activities or restrictions exist

                 in the study area due to existing soil types.

                 The following previous study reports were reviewed that were

                 directly or indirectly beneficial in accomplishing the

                 objectives of this study.

                     1)   11master Drainage Plan Southwest Escambia County",
                          1981, Henningson, Durham and Richardson, Inc.

                                              2-15

                    2)    "Erosion Report, Problems & Solutions Escambia
                          County, Florida", 1982, U.S. Department of
                          Agriculture.

                    3)    "Structural Controls Manual for Nonpoint Source
                          Pollution", 1980, Henningson, Durham and Richardson.

                    4)    An Assessment of Stormwater Management Programs"
                          for the Florida Department of Environmental
                          Regulation, 1985, Camp, Dresser & McKee

                    5)    "Tri-State Hurricane Evacuation Study", 1986,
                          Hazards Management Group, Inc. for U.S. Army Corps
                          of Engineers, Mobile District

                    6)    "Resource Management Plan, Escambia/Santa Rosa
                          Counties", 1985, Baskerville-Donovan Enginers, Inc.
                          for the Escambia/Santa Rosa Coast Resource
                          Management Committee

                    7)    "Stormwater Management Utility Report", 1986, Camp
                          Dresser & McKee, Inc. for the City of Tallahassee,
                          Florida

                    8)    "Availability and Quality of Water from the
                          Sand-and-Gravel Aquifer in Southern Santa Rosa
                          County, Florida", 1982 NWFWMD Water Resources
                          Special Report - 82-1

                The Master Plan developed by Henningson, Durham, and

                Richardson, Inc. in 1981, dealt with some of the same areas

                as this study. Evidently, none*of the structural recommen-"

                dations in that study were ever implemented. Unfortunately,

                efforts to obtain field information utilized in that study

                were unsuccessful. That data would have proven to be a tre-

                mendous supplement to data obtained in this study. The

                recommendations outlined in that study were reviewed based

                on today's regulatory climatel and though some of the struc-

                                            2-16

                 tural solutions in that report would be possible to imple-

                 ment, others would be quite difficult.

                 References 2-4 above were reviewed to investigate and eva-

                 luate various methods to control stormwater runoff and

                 ensure water quality. Some of the material in these

                 references will be utilized later in the report in Section

                 6, when guidelines for new developments are presented.

                 Reference 5 describes coastal flooding due to tidal surge

                 associated with different category hurricanes (1-5). That

                 report is very well done and informative. Since the flood

                 data presented is associated with tidal surge due to wind

                 and does not include the effects of heavy rainfall, it will

                 not be repeated in this report. This report will address

                 the effects of surface water runoff only.

                 Some of the information in reference 7 will be utilized when

                 stormwater funding sources are evaluated in Section 4.
                                                                           A

                 Based on the extensive search for hydrologic data in the

                 study area, it is apparent that a great need exists to

                 implement a hydrologic data collection network for the area.

                 Recording stream and rainfall, gages should be selectively

                 placed in the area so that a historic data base can be

                 developed. Another great need in the area is an extensive

                 subsurface investigation and the placement of groundwater

                                             2-17

                monitoring sites.so that groundwater profiles can be deve-

                loped.

                2.6 SOILS

                Soil structure significantly influences the drainage

                characteristics of an area, and the land lying within the

                study area is no exception. Although, nearly all of the

                soils are primarily sands or silty sands, there is signifi-

                cant variation in the ability of these soils to infiltrate

                stormwater.

                This variation is due primarily to the formation of the soil

                structure by nature. Those upland areas near the coast

                exhibit characteristics quite apart from soils lying within

                the interior of the study area.

                This variation is depicted graphically on Figure 2-4. Note

                that red shading denotes soils exhibiting good to excellent

                infiltration capabilities and that almost all of these soils

                are adjacent to coast lines. Blue shading depicts soils

                with very poor infiltration capabilities and is confined to

                low-lying swamps and marshes. These soils have a very high

                content count and have standing water much of the year.

                Toward the interior of the study area, there are vast expan-

                ses of soils with poor infiltration bordered by areas that

                have somewhat poor (yellow) infiltration capabilities.

                                          2-18

                 Due to a high water table and level.terrain, many of those

                 areas not shaded are subject to frequent flooding and are

                 currently unsuitable for most uses. Those areas shaded

                 yellow are also subject to frequent shallow flooding of

                 limited duration.

                 The primary factor contributing to the development of these

                 low infiltration soil structures is the level terrain.

                 These soils consist of a mixed textured sand with some orga-

                 nic content to a depth of three to four feet. Below this,

                 the material is chiefly composed of very fine textured sands

                 or sandy silts that support a high water table.

                 Consequently though the upper layers of soil are quite per-

                 meable, there is very little available storage capacity in

                 the soil structure to allow infiltration of stormwater.

                 Therefore, surface inspection of these soils during dry

                 weather can lead to erroneous conclusions regarding the

                 -infiltration capabilities of these soils.

                 Most of the soils along the coastal areas have very high

                 permeability and depth to the water table is greater than

                 six feet, in most cases. However, during periods of heavy

                 extend rainfall, especially the area south of Garcon Swamp,

                 the surface-runoff collects in isolated depressions and low

                 areas, containing soils that have poor infiltration capabi-

                 lities. These low areas fill up and overflow through

                                           2-19

                 natural drainageways. This concentrated flow of water over-

                 taxes the inadequate drainage system along Old Gulf Beach

                 Highway, resulting in water flowing across the roadway at

                 several locations. Therefore, here again, this is a case,

                 where, flooding is occurring, due to the natural terrain,

                 even though the majority of the soils in this case have good

                 infiltration capabilities.

                 This situation also occurs on Pensacola Beach. The soils on

                 Pensaola Beach consist of deep deposits of coastal sand

                 exhibiting excellent infiltration capabilities. However,

                 for large rainfall amounts, surface runoff does occurr and

                 this water collects in isolated low areas that quickly

                 become saturated. In these areas water will stand for days

                 without percolating into the ground. -Again, this will only

                 occur with large rainfall amounts.

                 Table 2-2 shows by drainage basin, the land areas and per-

                 centages of the total land area in each basin, of the four@

                 soil infiltration capability groups depicted on Figure 2-4.

                 The Bridge Creek/Herron Bayou Basin, for example, contains

                 soils with very poor to somewhat poor infiltration capabili-

                 ties over eighty-eight (88) percent of the.basin.

                 The Bayou Grande Headwaters has very poor to somewhat poor

                 infiltration for ninety-seven (97) percent of the soils in

                                           2-20

                                                               TABLE 2-2
                                                             SOILS ANALYSIS

                                                 Land Area Of          Land Area of        Land Area         Land Area
                                                 Soils With Good       Soils With          Of Soils          Of Soils
               Basin                 Area        To Excellent          Somewhat Poor       With Poor         With Poor
               Name                  (Ac.)       Infiltration          Infiltration        Infiltration      Infiltration
                                                     (Red)                 (Yellow)          (No Color)           (Blue)
                                                 (AC.)      %          (AC.)       %       (AC-)      %      (AC.)      %

               Bridge Creek/         3789         465     12           1088      29        2158      57         78      2
               Herron

               Bayou Grande          3994         130       3          1155      29        2606      65       103       3
               Headwaters

               Bayou Grande          2522         403     16            680      27          815     32       623      25

               Jones Swamp           1252           46      4           307      25          612     49       287      22

               Bronson Field         1467         510     34            202      14          574     39       163      13

               Paradise Beach          447        287     64               63    14           49     11         48     11

               Garcon. Swamp/        4426         877     20            699      16        1466      33      1384      31
               Garcon Bayou

               Coastal Area          3509        2746     78            263        7          50      1       450      14
               South of
               Garcon

               Perdido Key           4402        3814     87            141        3          32      1       415       9
               Innerarity Island

               Sandy Creek/          2237         611     27            700      31          825     37       101       5
               Weekley

               Tarkiln               1021         115     11            101      10          501     49       328      30

               Pensacola Beach       3317        2934     88              -                   -               383      12

                the basin. Conversely, Perdido Key and Innerarity Island,

                have highly permeable soils covering eighty-seven percent of

                the land area.

                Only twenty percent of  the Garcon Swamp - Garcon Bayou Basin

                has soils exhibiting good to excellent infiltration

                capabilities

                A definite correlation exists between the soil type in an

                area and the number and severity of drainage problems iden-

                tified.

                2.7 LAND USE

                2.7.1 EXISTING LAND USE

                Much of the study area is undeveloped at this time. As

                such, the opportunity exists to address many problems before

                they happen.

                Unfortunately, many of the developments that do exist  are-'

                experiencing problems with stormwater runoff and waste water

                treatment and disposal.

                Most of the developments that do exist are residential. The

                greatest concentration of these residential developments is

                along the coastal areas. Some of the larger subdivisions

                are Perdido Bay, Grande Lagoon, and Seaglades. All of these

                                             2-22

                are located in the southern or western end of the study

                area, and are located on or near coastal water bodies.

                Recent trends show new residential developments along U.S.

                98 and Dog Track Road toward the interior of tile study area.

                Commercial development  is currently very light and distantly

                spaced. Most of these   developments are single occupancy

                buildings such as convenience stores or repair shops. With

                the exception of Perdido Key, and Pensacola Beach, commer-

                cial strip development and shopping centers are almost non-

                existent.

                On Pensacola Beach, many of the developments are high-rise

                condominiums and specialty shops as would be expected for a

                resort community. There are also a sizeable number of

                single family residential areas on Pensacola Beach in close

                proximity to the commercial tourist developments. Many of

                these areas have year-round residents. It is important that

                new developments on the beach not impact these residential

                areas.

                Existing land uses, with the exception of Pensacola Beach,

                are shown on Figure 2-5. Note that two large government

                complexes, Sherman Field and Bronson Field are located

                within the study area.

                                           2-23

                Although these facilities exist in the area, they  are not

                being considered in this study.

                2.7.2. FUTURE LAND USE

                Escambia County is taking a  major step toward managing

                growth in the study area by  establishing zoning in southwest

                Escambia County. Zoning is   not established for Pensacola

                Beach, since property on the  beach is leased, not owned. The

                Santa Rosa Island Authority monitors development on

                Pensacola Beach.

                The effort to establish_zoning in the area will allow some

                control over development and enable better planning for

                facilities to serve the area.

                Figure 2- 6 is a preliminary map showing what zoning is

                anticipated for the area. Again, this map is subject to

                changes and revisions are forthcoming.

                Analyzing the various zoning categories present, it is

                apparent that a substantial portion of the study area will

                be zoned CN-Conservation. Under this zoning, County

                Commission Approval will be required for any uses other than

                wildlife sanctuarys, parks, or fire towers. since uses are

                not designated, any use is possible as long as County

                Commission Approval is obtained. The CN zoned areas were

                                             2-24

                 established utilizing National Wetland Inventory maps pre-

                 pared by the U.S. Department of the Interi or Fish and

                 Wildlife Service. The CN designated areas basically follow

                 the wetlands shown on these maps.

                 Most of the CN designated lands lie in the Bridge

                 Creek-Herron Bayou Basin, the Bayou Grande Headwaters, Jones

                 Swamp, and Garcon Swamp. Noteably, these basins were deter-

                 mined to have the greatest percentage of swamp land as indi-

                 cated previously in Section 2.4.

                 Most of the area not CN is designated as residential. Most

                 of the residential areas will have light to medium density

                 residential designations.

                 Areas of commercial zoning are isolated and appear to coin-

                 cide with existing commercial uses in the study area. Based

                 on the zoning indicated, commercial development will be

                 limited in the study area, and will have no significant
                                                                           A
                 impact on stormwater runoff.

                 Also, the areas designated for residential usage appear to

                 be appropriately zoned. However, some of the new areas must

                 utilize great care in managing stormwater when developed.

                                           2-25

                2.8 FLOOD MAP

                Figure 2.7 reflects the flood areas established by Stottler

                Stagg & Associates and GKY & Associates,,Inc., for the

                Federal Emergency Management Agency (FEMA). The figure is

                included herein 'to delineate the areas of expected flooding

                resulting from a 100-year storm event. A 100-year storm is

                expected to be equalled or exceeded on the average once in

                any 100-year period. Although the   recurrence interval

                represents the long-term average period between floods of a

                specific magnitude, rare floods could occur at short

                intervals or even within the same year. The risk of

                experiencing a rare flood increases  when periods greater than

                one year are considered.

                The FEMA revised the Federal Flood Insurance Rate Map (FIRM)

                for Escambia County on August 19, 1987. The FIRM generally

                contains specific information on expected flood heights near

                the coastal and bay areas. The inland areas are less        A

                detailed and usually depict only the expected flood area with

                no established flood heights. The FIRM was prepared for

                flood insurance'purposes and is used to establish minimum

                floor elevations for habitable buildings. It should be noted

                that the established flood elevations are a minimum. It is

                very possible to experience flood elevations in excess of the

                FIRM elevations due to inadequate stormwater controls. There

                are areas such as this that have experienced flooding which

                are not in a designated flood area.

                                            2-26

                                          LEGEND

                                          MAIN ROADS
                               ----STUDY AREA BOUNDARY
                               ------MAJOR         BASIN BOUNDARY

                                                                                                                            V
                                                                                                          BEACH

                                                                                                       saga**                          BR   GE       E
                                                                                                           B  0    N                    "@DGE
                                                                                                           B                r57'1 HER PN BAYOU
                                                                                                                                        D.A. = 5.920 SO

                                                                                                                                           --- 4*

                                                                                                                                           4f
                                                                                                                             S          @EK
                                                                                                                        IVE         B         A@
                                                                                                                        I   D.A.   2.06
                                               N                                              ------          ARKIN
                                                                                                                         ------- ------   -- --------

                                         w            E
                                                                                                                                0000.11f 11    0
                                               S
                                                5000'                                                                                       -----------
                                                                                       PERDIDO BAY                                         1% womo 00
                                                                                                                         1A

                                                                                                              '000m m I   I  GARCON SWAMP BASIN
                                                                                                        oft                     D.A.  6.06 SQ. MI.

                                                                                                                           _77-

                                                                                                          (10 P@ST!@cojq
                                                                                                              GO                      BIG

                                                                                                                                                    -Bo

                                                                                              W.10-01
                                                                                                                GULF OF MEXICO

                             LEGEND

                                            SWAMPS

                                            STREAMS
                                                                                                     FARADIS
                                            LAKES                                                    :$EACH

                                                        DEPRESSIONS
                                            ISOLATED
                                            AND SWAMPS
                                                                                                      BAON         Lr
                                                                                                      B
                                            MAJOR ROADWAY                                                               ..

                              . . . . . .   MAJOR BASIN      BOUNDARY

                                                                                                                   ui

                                              N
                                                                                                                  Im             4E
                                                                                                                  IWE E      B Y
                                                                                                                      D.A.'- 2.06
                                        W           E                                                    AR@6
                                                                                                                                    7f- - -

                                              S
                                                                                                                          too....
                                         1"    5000,

                                                                                                             - - -                ................
                                                                                   PERDIDO BAY

                                                                                                                                   ..............
                                                                                                                                     ..........
                                                                    1000                                              GARC ON
                                                                                                                           . . .... . ...........

                                                                                                                    ................ .... .
                                                                                                                    T. := .................
                                                                                                                              .... Tr
                                                                                                                                       wool,
                                                                                                                                        BEAC
                                  looe@                                                  .......... ....

                                                                                                                                     1xv,00
                                                                                                                                 BIG

                                                                                     p.
                                                                                          ........... ....

                                                                                                                  Waco
                                                                                                            OF
                                                                                                    GV-y

                               LEGEND

                   RED-SOILS WITH GOOD TO EXCELLENT INFILTRATION CAPABILITIES
                   YELLOW-SOILS WITH SOMEWHAT POOR INFILTRATION CAPABILITIES
                   BLUE-SOILS WITH VERY POOR INFILTRATION CAPABILITIES
                        (STANDING WATER)
                   NO COLOR-SOELS WITH POOR INFILTRATION CAPABILITIES

                                                                                        SURVEY
                                                                                        NOT .                @4,
                                                                                        AVAILABLE

                                          N

                                               E
                                      in  95000'                    PERDIDO BAY

                                                                                                          Ar
                           /0001@
                          or

                                                                                                      lo
                                                                                                           -BIG

                                     "ISO
                                                                   op

                                                                     GULF OF MEXICO

                             LEGEND

                             RES -RESIDENTIAL
                             COM-COMMERCIAL                                          RES
                             IND -INDUSTRIAL
                             AG -AGRICULMRAL
                             INST-INSTMMONAL
                                                                         @O M
                             GOV-. GOVERNMENT-
                                   BASIN BOUNDARY
                                                                                                           ----- -----
                                                                                 GO

                                                                                             NNW.

                                      N

                                 w        E                              ------ ---- -------------  j---- -- -------

                                     S
                                      5000'                        PERDIDO BAY                              com
                                                                                               - --- ---------------

                                                                                                             RE
                                                                                                 -----------
                                                                com

                                                                           E L mi
                                                         @RE                         GOV                 B\G V.@,GOOO

                                                                                    GULF OF MEXICO

                           LEGEND
                           R-1   -SINGLE FAMILY      4 D. U. PER  ACRE
                           R-2   -SINGLE FAMILY      7 D. U. PER  ACRE
                           R-3   -1 & 2 FAMILY      10 D. U. PER  ACRE
                           R-4   -MULTI FAMILY      15 D. U. PER  ACRE
                           R-5   -URBAN RESIDENTIAL/OFFICE        20 D. U. PER ACRE                 6              ------ -------
                                  NEIGHBORHOOD         25 D.U. PER   ACRE
                           R-6   -COMMERCIAL TRANSITION - LIMIT     TO 4000  S. F. BLDG.                                    00
                           RR    -RURAL RESIDENTIAL 1 D.U. PER      ACRE                               VMS
                           C-1   -RETAIL COMMERCIAL
                                                                                               ARR
                           C-2    GENERAL COMMERCIAL - MAUS
                           ID-1  -I.JGHT INDUSTRIAL - NON CUMULATIVE
                           CN     CONSERVATION - REQUIRES COUNTY COMMISSION
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                              3.0 PROBLEM AREA IDENTIFICATION

                3.1 SOURCES OF INFORMATION

                One of the major tasks in this study was to identify

                existing drainage problems.. Due to the large area involved,

                this was a difficult and time consuming process. To

                accomplish this, a number of sources were utilized. Those

                sources are as follows:

                    1)   Interviews with personnel, Escambia County

                         Engineering and Road Operations, to identify major

                         flooding problem areas and obtain feedback con-

                         cerning causes of flooding.

                    2)   Field inspection of flooding occurring due to heavy

                         rainfall of August 12-17, 1987.

                    3)   Review floo ding complaint records from Escambia

                         County Road Operations for the years 1960 - summer,

                         1987.

                    4)   Field interviews with citizens: A number of citi-

                         zens were contacted to discern the scope and nature

                         of-the drainage problems experienced.

                    5)   Interviews with personnel of the Florida Department

                                           3-1

                          of Environmental Regulation to determine what areas
                          were continuing'problems.

                     6)   Interview and inspect drainage problem areas on

                          Pensacola Beach with personnel of the Santa Rosa

                          Island Authority.

                     7)   Newspaper accounts of flooding in the study area

                          associated with August, 1987 rainfall.

                     8)   A public meeting was held on November 17, 1987

                          where citizen survey questionnaires were distri-

                          buted and citizen input was received.

                3.2 PUBLIC MEETING

                A questionnaire was distributed at the public meeting

                November 17, 1987 which addressed specifics regarding the

                type and frequency of flooding that had been experienced.

                This questionnaire is included here as Exhibit 3-1.

                The public meeting was  held to brief the citizenship in the

                study area o n progress and findings of the study and to

                solicit public input regarding drainage problems and their

                solutions.

                Few areas, that had not already been identified, surfaced at

                the meeting, but valuable insight into how the citizenship

                viewed their problems was obtained. Many citizens felt that

                                           3-2

                an improved maintenance program for 'existing drainage faci-

                lities would alleviate their problems, while others felt

                that minor drainage improvements would significantly reduce

                the problems they experience.

                Many of the citizens felt that their drainage pr oblems 'have

                been compounded by roadway construction in their areas.

                Roadways cited have been Blue Angel Parkway (S.R. 173),

                Sorrento Road (S.R. 292) U.S. 98 (S.R. 30) and Old Gulf

                Beach Highway (C.R. 292). These complaints deserve con-

                sideration because of the widespread unanimity held by the

                citizens in the area.

                Due to the nature of,the area and the lack of historic data,

                citizen input has been the primary source for identification

                of drainage problems.

                3.3 PROBLEMS IDENTIFIED

                Based on the information provided by the various sources,

                drainage problem areas were identified. The locations iden-

                tified a description of the problems(s) being experienced,

                and the probable causes(s) of the problems(s) are shown on

                Table 3-1.

                These locations and the type of flooding experienced are

                shown on Figures 3-1 and 3-2.

                                             3-3

                                   SOUTHWEST ESCAMBIA COUNTY
                                         DRAINAGE STUDY
                                         QUESTIONNAIRE

                 RESPONDENT'S NAME:

                 RESPONDENT'S PHONE:

                 RESPONDENT'S ADDRESS:

                 Circle approximate location of residence or business on
                 attached map. Do not respond to this questionnaire unless
                 you have legitimate interest(s) within the study area shown
                 on the attached map.

                 RETURN TO:  Barrett Daffin and Carlan, Inc.
                             ATTN: Mr. Wayne G. Newsome, P.E.
                             f. 0. Drawer 12526
                             Pensacola, Florida 32573

                             Phone: (904) 433-5601

                 1. Have you ever experienced flooding in your present loca-
                     tion?

                           Yes             No

                 2.  What type(s) of flooding have you experienced? Check
                     below.

                     a)   Severe yard flooding of extended duration
                     b)   Severe street flooding  _
                     c)   Flooding of business or residence

                 3.  How many times have you experienced flooding to type(s)
                     stated above?

                     a)   Severe yard flooding,        time(s).
                     b)   Severe street flooding,  _      time(s).
                     c)   Flooding of business or residence,         time(s).

                 4.  What date(s) do you recall flooding occurring? If you
                     cannot remember exact date(s), give approximate date(s).
                     If you have no idea, leave blank.

                                                                    EXHIBIT 3-1

                                                              TABLE 3-1
                                                       DRAINAGE PROBLEMS AREA                           Page 1 of 5

                                                             PROBLEM
                  BASIN             LOCATION                 DESCRIPTION                  PROBABLE CAUSE(S)

                  Bridge Creek-     U.S. 98 & Cessna         Yard Flooding                Inadequate Conveyance
                  Herron Bayou                               Street Flooding              Along U.S. 98

                                    U.S. 98 & Skyhawk        Yard Flooding                Inadequate Conveyance
                                                             Street Flooding              Along & Under U.S. 98

                                    U.S. 98 & Ferguson       Flooding of                  Inadequate Conveyance
                                    Field                    Runway @ U.S. 98             U. S. 98

                                    U. S. 98 & Aileron       Street Flooding              Inadequate Conveyance
                                                             Yard,Flooding                U. S. 98

                                    Aileron    South of      Street Flooding              Inadequate Movement of
                                    U. S. 98                 Yard Flooding                Water Through Low Area
                                                                                          High Water Table - No
                                                                                          Place to Drain

                                    U. S. 98    500' +       Flooding of Apartments       No Positive Outlet'For
                                    West of Aileron          Street Flooding              Stormwater
                                                             Yard Flooding

                                    Dog Track Rd - East      Yard Flooding                Too Much Water For
                                    Side Just South of                                    Roadside Ditch Lack of
                                    Entrance to Greyhound                                 Channelization Upstream
                                    Race Track                                            Yard Elevation Low

                                    Dog Track Rd - East      Yard Flooding                Inadequate Conveyance
                                    Side of Road 1250'                                    Along & Under Dog Track
                                    Southeast of Tanton                                   Road
                                    Road

                                                             TABLE 3-1
                                                       DRAINAGE PROBLEMS AREA                           Page 2 of 5

                                                            PROBLEM
                  BASIN             LOCATION                DESCRIPTION                   PROBABLE CAUSE(S)

                  Bayou Grande      Dog Track Road          Severe Yard Flooding          No Positive Outfall
                  Headwaters        East Side of Road       Minimal Structural            No Culvert Under Dog
                                    From 2550' + North-     Flooding                      Track Road - Only Outlet
                                    west of Blue Angel                                    Through 2-30" R.C.P.
                                    Parkway                                               Culverts at Blue Angel
                                                                                          Parkway - Which submerge
                                                                                          During Heavy Rains

                                    Dog Track Road          Severe Yard Flooding          Too Much Water Being
                                    East Side - From        Flooding of Barns             Carried Down Dog Track
                                    Blue Angel Parkway      & Utility Sheds               Road - Inadequate
                                    Southeast 3250'                                       Culvert Size Under Dog
                                                                                          Track Road Approximately
                                                                                          2750' South of Blue
                                                                                          Angel Parkway - Problem
                                                                                          is Compounded by Under-
                                                                                          Sized Driveway Culverts

                                    Sorrento Rd - 200'      Yard Flooding                 Inadequate Maintenance
                                    West of Blue Angel                                    of Roadside Ditch,
                                    Parkway                                               Driveway Culvert &
                                                                                          Culvert Under Roadway -
                                                                                          Problem Has Been
                                                                                          Addressed

                                    North Loop Road -       Yard Flooding                 Inadequate, Undersized
                                    400' West of Blue                                     & Not Maintained Drain-
                                    Angel Parkway                                         age Ditches

                                    10360 Etheridge Drive Yard Flooding                   New Culvert Under Drive-
                                    200-300' Wes@t of                                     way Inadequate - Also
                                    South Loop Road                                       Water Being Turned 900 -
                                                                                          Roadside Ditch Inade-
                                                                                          quate

                                                           TABLE 3-1
                                                     DRAINAGE PROBLEMS AREA                         Page 3 of 5

                                                          PROBLEM
                  BASIN           LOCATION                DESCRIPTION                 PROBABLE CAUSE(S)

                  Bayou Grande    South Loop Road -       Yard Flooding               Inadequate Facilities
                  Headwaters      West of Blue Angel                                  High Water Table
                  (continuedY     Parkway

                                  West Side South         Limited Structural          Lower Floor of Garage
                                  Loop Road - Just        Flooding - Yard             Apartment Floods -,Asso-
                                  North of Etheridge      Flooding                    ciated with Etheridge
                                                                                      Drive Problem Discussed
                                                                                      Above

                                  9619 Sidney Road        Severe Yard Flooding        Inadequate Conveyance
                                  East of Blue Angel      Garage Flooding             Downstream - Inadequate
                                  North of North Loop     Street Flooding             Ditch
                                  Road

                  Bayou Grande    Robertson Road          Yard Flooding               Inadequate Drainag e
                  Basin                                   Water Quality               System For Unpaved Road-
                                                          Street Flooding             way Maintenance For
                                                          Roadway Washes              Ditch Draining Sherman
                                                                                      Field Needed

                  Innerarity      Unpaved County Roads    Water Quality               Erosion of Roadways
                  Area

                  Garcon Swamp    Doug Ford Drive         Street Flooding             Inadequate  Facilities/
                  Basin                                                               Inadequate  Maintenance
                                  Arapaho Drive           Street Flooding             Inadequate  Facilities/
                                                                                      Inadequate  Maintenance

                                  Bauer Road North of     Street Flooding             Inadequate  Facilities
                                  Bridge over Garcon
                                  Swamp

                                                             TABLE 3-1
                                                       DRAINAGE PROBLEMS AREA                           Page 4 of 5

                                                            PROBLEM
                  BASIN             LOCATION                DESCRIPTION                   PROBABLE CAUSE(S)

                  Gulf Beach        Treasure Hill           Structural Flooding           Inadequate Facilities
                  Highway                                   Street Flooding
                  (Coastal Ai@ea
                   South of         Grand Lagoon  North     Structural Flooding           Inadequate Facilities/
                   Garcon Point)                            Street Flooding               Inadequate Maintenance
                                                            Water Over Roadway

                                    Grand Lagoon South      Street Flooding               Inadequate Facilities
                                                            Water Over Roadway
                                                            Erosion of Roadway

                                    Chanteclaire Drive      Structural Flooding           Inadequate Facilities
      30
                                    Seaglades               Private Property              Inadequate Facilities
                                                            Flooding

                                    Gulf Beach Highway      Water Over Roadway At         Inadequate Facilities
                                                            Several Locations

                  Sandy Creek       Bauer Road              Water Over Roadway            Inadequate Facilities
                  Basin

                                    Seratine Drive          Private Property              Inadequate Maintenance
                                                            Flooding

                  Bronson Field     Wildwood Lakes          Street Flooding               Inadequat Facilities
                  Basin

                                    Bauer Road              Water Over Roadway            Inadequate Facilities

                  Pensacola         Ft. Pickens i@oad       Severe Street Flooding        No Positive Outlet For
                  Beach             @ Baywatch                                            Stor mwater

                                                                TABLE 3-1
                                                         DRAINAGE PROBLEMS AREA                             Pag e 5 of 5

                                                               PROBLEM
                   BASIN             LOCATION                  DESCRIPTION                   PROBABLE CAUSE(S)

                   Pensacola         Via DeLuna Drive          Structural Flooding           No Positive Outlet For
                   Beach             Between Avendida   11     One Residence Yard            Stormwater House is in
                   (continued)'      and Avendida 12           Flooding                      Low Area

                                     Between Via DeLuna        Yard Flooding                 No Positive Outlet For
                                     and Maldonado Drive                                     Stormwater

                                     End of Cul-De-Sac.        Street Flooding               No Drainage For Street
                                     Esenada Uno               Yard Flooding

                                                                                                                                                                                                                                     o

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                                           C FLOODING OfPRIVATE PROPERTY.'...

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                             4.0 FUNDING OF STORMWATER MANAGEMENT

                 A major problem facing local governments today is finding a

                 way to fund needed stormwater managment programs and

                 drainage infrastructure renovations. Over the years,

                 governments have learned that regulatory programs alone will

                 not deal with the complex requirements of an effective

                 stormwater management program.

                 Those funding methods available are as follows:

                     1)   Special assessments

                     2)   Ad valorem tax increas es

                     3)   Grants

                     4)   Development impact fees

                     5)   Stormwater as a utility

                 All of the meth ods listed are legitimate revenue sources for
                 stormwater management; however, each method has drawbacks"

                 when it comes to implementation.

                 4.1 SPECIAL ASSESSMENT

                 In the view of many, funding of drainage should be provided

                 by those directly benefitting from the improvements. As will

                 be shown, only the most minor improvements can be funded by

                                             4-1

                 assessing only those who benefit directly from the improve-

                 ment.

                 Table 4-1 shows the total costs associated with alternatives

                 developed in Section Five (5). The cost/acre figures shown

                 are based on the total acreage drained by the improvements.

                 This does not mean that all the acreage will benefit from

                 the improvements.

                 Some large tracts of low lying swamp land receive no

                 drainage improvement, but do contribute runoff to the

                 improvements.

                 Therefore, an assessment based on total acreage drained in

                 each area would range from $520.00 to $3,30 0.00/acre, with

                 an average cost/acre equal to $1,500 per acre drained.

                 The cost/acre figure from Doug Ford Drive is based on the

                 acreage accessed by the roadway, not drainage area.

                 At a cost/acre of $1,500.00, an owner of twenty (20) acres

                 of undeveloped property would have to pay an assessment of

                 $30,000.00. This is an exorbitant price to pay for property

                 that may not even be developable.

                 One solutio-n to this inequitable situation is to base the

                 assessment on the number of parcels in a basin and charge

                 every parcel the same, regardless of size. Again, this is

                                             4-2

                not equitable since owners of large-'tracts of land would not

                pay their fair share.

                Another choice would be to base the assessment on the imper-

                vious acreage of a parcel. In that case, if a parcel is not

                developed, no assessment is paid. The only problem with

                this solution is that probably less than twenty (20) percent

                of any of the larger areas is impervious. Therefore, the

                assessment value per acre would have to be at least five

                times the previous rate in order to fund the plan. If the

                average percentage of imperviousness is twenty percent (20),

                then the assessed value per impervious acre would be

                $7,500.00. If the average percentage of imperviousness is

                ten (10) percent, then the  assessed value increases to

                $15,000.00 per impervious acre. For a typical single family

                home containing approximately 2700 square feet of impervious

                roof, parking, and drive, the one time assessment would be

                approximately $930.00.                                     X

                This is not an unreasonable assessment for a house

                experiencing a drainage problem that will be solved using

                this money. But for those not experiencing drainage

                problems, or those not benefitting from the solution, it is

                still an exorbitant price to pay. However, if that resi-

                dence or business is in a basin or subbasin where problems

                are being experienced, then the runoff they contribute must

                                             4-3

                be dealt with by the downsteam owner'. Hence, it is not

                unreasonable to expect someone to pay a share of the solu-

                tion cost to a problem they are helping create.

                Even though this last assessment procedure seems to work

                well and would be fair to all involved, there is still a

                problem. Since the cost is based on acres drained, the line

                defining that acreage becomes an issue. For instance, in

                the Bridge Creek Basin there are 3790 acres lying in the

                study area. The acreage drained by all improvements pro-

                posed is only 1475 acres. In this case, people owning pro-

                perty on the west side of Dog Track Road would not be

                assessed, yet immediately across the road, those owners

                would be assessed because they are included in the area

                drained by the improvements. For this reason, it does not

                seem prudent to establish assessment as a means of funding

                stormwater improvements unless that assessment applies to

                everyone in a basin.
                                                                           A

                In the Bridge Creek Basin, for example, if everyone in the

                basin is assessed to help fund improvements, the cost/acre

                would drop from $2,350.00/acre to @914.00/acre- If imper-

                vious acreage is used in determining the required assessment

                rate and assuming ten (10) percent of the basin is imper-

                vious, then the cost/impervious acre would be $9,140.00.

                                            4-4

                                                             TABLE 4-1

                                                                 COST/ACRE    COST/ACRE     TOTAL        TOTAL
                                                       AREA        DRAINED     DRAINED      COST         COST
                  BASIN                              DRAINED      ALT. 1       ALT. 2       ALT. 1       ALT. 2

                  Bridge Creek                         1475        $2,645      $2,350*    $3,901,000 $3,465,000*

                  Bayou Grande Headwaters

                       North                           730            937*      3,200        684,000* 2,330,000
                       South - Pleasant Grove          790         1,000*       1,781        797,000*

                  Pensacola   Beach

                       Ft. Pickens                        5        4,600*       8,800         23,000*      44,000
                       Ensenada Uno                       3        8,000          -           24,000           -

                  Coastal:Area South of Garcon
                  (Old Gulf Beach Highway)

                       Grande Lagoon                   200         1,975        1,600*       395,000      320,000*
                       Seaglades                         30        1,166          -           35,000           -
                       Quina Vista                     250            520         -          130,000           -
                       Treasure Hills                  120         3,300          -          400,000           -

                  Perdido Bay Resort

                       Doug Ford                       500            304         -          152,000           -
                       Arapaho                           73 lots   1,356          -           99,000           -
                       Zuni Circle                      -                         -           15,000           -

                    Selected Alternate                                            Total     $6,295,000.00
                                                                                 Say 6.3 million

                 Therefore, the assessment  to a typical 2,650 square foot

                 residence would be around  $556.00.

                 Based on this analysis, it would seem advisable to establish

                 assessment districts corresponding to the major   basin deli-

                 neations presented in this report. If this funding

                 mechanism is considered, it is recommended in each major

                 basin, an accurate estimate of the impervious area be

                 obtained so that further evaluation of an assessment based

                 on impervious area can be made.

                 If an assessment, based on impervious area,   is utilized,

                 then accurate detemination of that area for   each parcel must

                 be made, Some of this information is available through the

                 tax assessor's office, but updating may be required.

                 4.2 AD VALOREM TAX INCREASES

                 The first step in analyzing ad valorem taxes as a funding

                 source was to obtain sufficient tax and parcel information"

                 to determine the study area tax base.

                 This task was difficult and time consuming. Most of the

                 information ws provided by Escambia County Engineering as

                 xeroxed copies of tax rolls for those sections in the study

                 area. Whether this information is the most recent was not

                 known.

                                             4-6

                 However, it does provide sufficient.information to get a

                 general idea of how much tax increase in the study area

                 would be required to fund the improvements.

                 The total cost of stormwater improvements proposed for the

                 study area is approximately 6.3 million dollars. If all of

                 this money were borrowed on a fifteen year payback period at

                 seven percent interest, the required annual income to meet

                 the debt would be close to $900,000.00 per year. It is not

                 known what interest rate would be available to the County,

                 but seven (7) percent will be used here to demonstrate

                 funding requirements.

                 The current non-exempt tax base in the study area is

                 approximately 245 million dollars. To fund the stormwater

                 improvements in the study area, the tax rate must be

                 increased from $16.00 per thousand dollars of non-exempt

                 assessed value to $20.00 per thousand dollars of assessed

                 value.

                 Based on this tax rate, a typical home assessed at eighty

                 thousand dollars with a twenty-five thousand dollar

                 homestead exemption would experience an annual tax increase

                 of two hundred twenty ($220.00) dollars. This would not be

                 acceptable to many homeowners in,the area.

                 Another problem with this funding source is insuring that

                                             4-7

                 the increased revenue is earmarked for drainage improve-

                 ments in the study area. There would probably be additional

                 expenses required to set up an accounting system that would

                 separate out those funds to be used for drainage improve-

                 ments-in the study area.

                 The advantage of this revenue source is that it will con-

                 tinue to provide funding forever and will grow with develop-

                 ment of the study area.

                 The disadvantages are the inability to track the funds

                 received from this source and the anticipated unpopularity

                 this action would have with the taxpayers in the study area.

                 4.3 GRANTS

                 During the course of this study, a number of agencies were

                 contacted regarding grant funds that may be available to

                 local governments to inact stormwater improvements and to

                 upgrade the existing drainage infrastructure.

                 The response received from almost every agency contacted was

                 not optimistic. The fact is, there are very few funds

                 available for funding stormwater improvements, and the State

                 and Federal government is placing the burden of funding on

                 local governments.

                 Exhibits 4-1 and 4-2 are responses received from two of the

                                             4-8

                 agencies contacted. Other agencies"contacted were the

                 Florida Department of Transportation and the United States

                 Environmental Protection Agency. West Florida Regional

                 Planning was also contact@ed regarding any knowledge they may

                 have of possible grant source s.

                 The only somewhat positive response received is from the

                 Department of Community Development in Escambia County

                 (Exhibit 4-2). In this response, it is possible that some

                 areas may qualify for limited funding of infrastructure

                 improvements.

                 The Florida Department of Transportation has small amounts

                 of money available to counties through their maintenance

                 Division. This money is generally intended for maintenance

                 activities, but can be utilized to upgrade the existing

                 infrastructure. However, funds are limited and many Coun-

                 ties are vying for the money. Based on conversations with
                 the F.D.O.T., the maximum money available would be two to"

                 three hundred thousand dollars.

                 In general, grants should not be considered a reliable pri-

                 mary funding source. The monies simply are not there in

                 sufficient quantity to implement a program. However, in

                 some areas, money may be available, and can be used as a

                 secondary funding source.

                                            4-9

                 4,4 DEVELOPMENT IMP ACT FE ES

                 To utilize impact fees on development as a primary funding

                 source for implementation of the stormwater,management plan

                 would probably not result in sufficient funds.

                 The major problem with this singular funding source is that,

                 although there is growth in the area, it may be a long time

                 before enough new developments are started to begin to fund

                 improvements.

                 This means that it may take a number of years to implement

                 solutions due to the lack of funds and the uncertainty

                 always exists as to how much revenue can be expected.

                 Another factor that limits this as a primary funding source

                 is the large amount of acreage in the study area that simply

                 cannot be developed because it is a swamp or wetland.

                 In other words, the number of new developments are limited

                 by the topography of the area.

                 Consideration of impact fees on development as a secondary

                 funding source is viable. This money could be used to

                 augment funds obtained throQgh other sources.

                                             4-10

                Again, the primary disadvantages with this funding mechanism

                is the long time it would take to accrue funds and the

                uncertainty of when and how much revenue would be available

                t,-irough this source.

                                           4-11

                 4.5 STORMWATER AS A UTILITY

                 The current trend by many local governments is to approach

                 funding of stormwater management by treating drainage as a

                 utility, much like gas, water, or sewer is handled by

                 municipalities.

                 Under this funding mechanism, every user of the utility pays

                 his fair share of the cost to operate the utility.

                 In Exhibit 4-1, the recommendation is made to explore this

                 option as a funding source. In fact, cities such as

                 Tallahassee, Florida, have already implemented the utility
                 fees to fund drainage projects.(1)

                 This funding mechanism would need to be applied to the

                 entire county, not just this study area. It should be

                 accompanied by a stormwater master plan for the entire

                 county.

                                                                           A

                 In.Tallahassee, utility fee rates are based indirectly on

                 the impervious area contributing stormwater runoff. The

                 impervious area is used to determine the number of single-

                 family unit equivalents to 265.9 square feet in Tallahassee

                 and various other surveys conducted establish this value

                 between 2600 and 2700 square feet.

                     "Stormwater Mangement Utility Report for the City of
                    Tallahassee", February 1986, Camp, Dresser & McKee, Inc.

                                           4-12

                 The utility fee rate for a single family unit will need to

                 be determined by further study of the number of single

                 family units in the Escambia County versus revenue require-

                 ments to fund stormwater management for the entire county.

                 As a point of comparison, the most expensive alternative

                 for the City of Tallahassee resulted in a graduated fee rate

                 that increase over a five year period from $1.50/SFU/Month

                 to @3.00/SFU/Month. It is anticipated that these numbers

                 are within the range reasonably expected to fund a storm-

                 water management program in Escambia County.

                 The advantages of this funding source are as follows:

                     1)   Fair and equitable contribution by each user of the

                          utility.

                     2)   Provides a reliable and continuous funding source.

                     3)   Economic impact is low when compared to other
                                                                           A

                          funding sources.

                     4)   Funding is woven into a comprehensive master plan

                          for the entire county.

                 The disadvantages of this funding mechanism are as follows:

                                           4-13

                      1)   Requires development of a master plan for the

                           entire county to determine where and when revenue

                           will be spent.

                      2)   County is obligated to provide the service to the

                           user, as with other utilities.

                      3)   Must be implemented countywide.

                      4)   Additional study of this funding source is recom-

                           mended prior to implementation.

                 4.6 CONCLUSION

                 Based on the various funding mechanisms evaluated, the two

                 primary sources of revenue are special assessments and

                 stormwater as a utility.

                 Secondary funding through grants is possible though

                 available money will be limited. Also, secondary funding
                 could be obtained by placing impact fees on development, b'ut

                 revenue from this course is not likely to meet funding

                 needs.

                 If special  assessment funding is implemented, it would

                 reduce the  impact to individual property owners, if the

                 assessment  is made against all property owners in a basin

                 and is based on impervious area, rather than acreage.

                                              4-14

                If stormwater as a  utility is implemented, it should be

                applied countywide  and be incorporated into a countywide

                stormwater master plan.

                                           4-15

                                                STATE OF FLORIDA
                           DEPARTMENT OF ENVIRONMENTAL REGULATION

                                                     Ok

                                                                                           BOB MARTINEZ
             TWIN TOWERS OFFICE BUILDING                                                     GOVERNOR
             2600 BLAIR STONE ROAD
             TALLAHASSEE. FLORIDA 32399-2400                                            DALE TWACHTMANN
                                                                                             SECRETARY

                                                      E OF FLO

                                               November 19, 1987

                                                                               BARIZET7-
                                                                                        7--

                 Mr. Wayne G. Newsome
                                                                                            1987
                 Barrett, Daffin and Carlan, Inc.                                  NOV 2   01      .1
                 Post Office Drawer 12526                                                         -T
                                           -2526
                 Pensacola, Florida  32573

                 Dear Mr. Newsome:

                 This letter is in response to  your letter of November 17 regarding grant
                 funds for local government stormwater improvements. Please be advised
                 that, at this time, there are no state or federal grant programs for such
                 purposes. The state is considering a state revolving loan program to
                 assist local governments and the 1987 Federal Clean Water Act does include
                 some funding for stormwater implementation. However, the dollar amounts
                 are small, the demands are great and implementation is down the road.

                 In summary, local governments will need to develop local funding sources
                 for upgrading their stormwater infrastructure. I strongly recommend the
                 implementation of a stormwater utility in an expedient manner. A dedicated
                 funding source such as the utility can be used for the development and
                 implementation of a master stormwater management plan. Such a plan will be
                 needed to meet the requirements of the 1985 Growth Management Act and
                 Section 405 of the Clean Water Act which will require local governments to
                 obtain NPDES stormwater permits beginning in 1989.

                                                     Sincerely,

                                                     Eric H. Livingston
                                                     Environmental Administrator
                                                     Nonpoint Source Management Section

                 EHL/sps

                                        Protecting Florida and Your Quality of Life EX H IBIT 4- 1

                                                      BOARD OF COUNTY COMMISSIONERS
                                                                       ESCAMBIA COUNTY, FLORIDA
                                                                               223 PALAFOX PLACE
                                                                                  P.O. BOX 1591
               PHILLIP M. (PHIL) WALTRIP                                PENSACOLA, FLORIDA 32597-1591
                 DISTRICT ONE                                                  TEL. (904) 436-5783
                                                                               [SUNCOM) 682-5783
               KENNETH J. KELSON
                 DISTRICT TWO                                        Department of Community Services
               WILLIE J. JUNIOR                                            1190 W. Leonard          Street
                 DISTRICT THREE                                                        Suite 3
               MURIEL W. WAGNER                                             Pensacola, FL           32501
                 DISTRICT FOUR                                                     (904)436-9342

               GRADY ALBRITTON
                 DISTRICT FIVE
                               November      23, 1987

                               Mr. Wayne G. Newsome
                               Barrett, Daffin and Carlan, Inc.

                               P. 0. Drawer 12526
                               Pensacola, FL 32573-2526

                               Re: Stormwater Management Plan                     for
                                      Southwest Escambia County

                               Dear   Mr. Newsome:

                               Per earlier phone conversations with your firm, Community Development Block
                               Grant is the primary funding resource available to this Department for
                               activities such as that noted above. Proects which assist low/moderate
                               income families are generally eligible, however, the funding level is
                               limited.       As we discussed, staff is currently examining possible projects
                               for next year which will incorporate the area being studied, however, a
                               detailed survey will be necessary to document the low/moderate income
                               standing of various neighborhoods within the study area prior to commitment
                               of CDBG funds.           When the Management Plan is complete, we will be glad to
                               examine funding possibilities.                    Additionally, though currently unclear,
                               other state and/or federal funding could become available in relation to
                               the comprehensive plan and its related implementation.

                               Should you have questions please call me at                          436-9342.

                               Sincerely,

                               Randy Wilkerson
                               Director
                               Community Services

                               RW/uh
                               pc:   Wayne Peacock
                                     Gary Bishop

                                                                              Pensacola
                                                                         Florida's First Place City         EXHIBIT 4-2

                                5.0 PROBLEM DESCRIPTIONS AND
                              STRUCTURAL ALTERNATIVES EVALUATED

                In this section, structural solutions will. be presented for

                the drainage problem areas identified in section 3.0. These

                problem areas will be provided with one or more solutions or

                alternatives. Alternatives are developed for each major

                basin in the study area, as described in Section 2.3. These

                alternatives for each basin are evaluated in five categorie  s

                as outlined on Exhibits 5-1 and 5-2. The alternative

                obtaining the highest cumulative point total for those five

                categories is the preferred alternate for that ba sin.

                5.1 BRIDGE CREEK BASIN

                The Bridge Creek-Herron Bayou basin is one of the larger

                basins delineated in the study area. The portion of the

                basin within the study area boundary totals 5.92 square

                miles or approximately 3790 acres. This basin is bordere(T

                on the north by U.S. 98 and extends to Bauer Field Road

                (C.R. 293) on the east and almost to Fairfield Drive on the

                east. The southern basin boundary adjoins the headwater for

                Sandy Creek and Bayou Grande.

                Most of the basin drains to Bridge Creek from the east side

                of Dog Track Road. Approximately three hundred and forty

                                           5-1

                               PROCEDURE FOR THE EVALUATION OF
                                   STRUCTURAL ALTERNATIVES

                        ECONOMIC IMPACT

                      A. Construction     Implementation Cost

                      B.  Anticipated Maintenance Cost (compute present
                          value of maintenance based on 25 yr. design
                          period, i = 8%)

                      C.  Evaluate cost/acre in the contributing drainage
                          basin for which the solution will be effected.

                      D.  Assign points to each alternative, assigning the
                          highest number to the alternative with least
                          cost/acre.

                        ENVIRONMENTAL EVALUATION (including water quality)

                      4.  Alternative will have positive impact.

                      3.  No change in environment

                      2.  Alternative will result in temporary change in
                          environmental quality with equal or improved con-
                          ditions over a period of time.

                      1.  Alternative will have adverse impact on environ-
                          ment.

                        LEVEL OF SERVICE PROVIDED

                      4.  Alternative eliminates flooding for all frequen-
                          cies up to a 25 year return interval storm.

                      3.  Alternative eliminates flooding for more frequent
                          events, flooding at a slightly reduced level for
                          the less frequent storm events will still occur,
                          however, the duration of flooding is significantly
                          reduced.

                      2.  Flooding level for most storms remain unchanged,
                          however, flooding duration is reduced.

                      1.  No change in flooding level or duration.

                                                                  EXHIBIT 5-1

                  @IV.  DOWNSTREAM IMPACTS

                       4.  Alternative will have positive downstream impacts
                           both water quantity and quality.

                       3.  Alternative results in no change in downstream
                           water quantity or quality.

                       2.  Alternative results in no adverse impact in water
                           quantity downstream, but may adversely impact
                           downstream water quality.

                       1.  Alternative has adverse impacts both in water
                           quantity and quality.

                *V.     HUMAN ISSUES EVALUATION

                       1.  Plan alleviates or eliminates structural flooding
                           and damages and the human distress associated with
                           flooding.

                       2.  Plan alleviates distress caused by severe street
                           flooding and the inability of people to enter and
                           leave their home or business.

                       3.  Plan alleviates distress and health hazards caused
                           by extended duration yard flooding.

                       4.  Plan does not require the relocation of residents
                           or businesses in order to enact.

                       5.  Plan is an attractive addition to the neigh-
                           borhood.

                  In order to avoid unfair weighing of the human issues
                category, each subcategory (1-5) under the human issues
                category will be assigned a value of (1-4) for each alter-
                native with the highest point rating indicating the highest
                degree of achievement in the subcategory described. The
                points for 'each subcategory will be totaled and divided by
                five (5) to obtain the relative point value for the human
                issues category for each alternative.

                                                                  EXHIBIT 5-2

                 acres drains north unde U.S. 98 to Herron Bayou. The

                 remainder of the basin drains directly into Bridge Creek

                 from the west side of Dog Track Road.

                 This basin is sparsely developed with residential and com-

                 merical concentration along U.S. 98 and Dog Track Road. As

                 stated previous ly, almost,1/4 of the basin is swamp land

                 and, with the exception of a narrow band bordering Bridge

                 Creek, most of the land is level. Soils in the majority of

                 the basin exhibit somewhat poor to poor infiltration charac-

                 teristics and have a water table to within one to two feet

                 of the ground surface much of the year.

                 The major drainage problems occurring in the basin are along

                 U.S. 98 and Dog Track Road, with less severe problems

                 occurring on Aileron Drive. Those streets impacted by the

                 flooding occurring along U.S. 98 are Cessna Drive, Skyhawk

                 Drive and Aileron Drive. Flooding also occurs at the inter-

                 section of Blue Angel Parkway and U.S. 98, and property on'

                 the east side of Blue Angel Parkway experiences significant

                 flooding.

                 The flooding along Dog Track Road is almost exclusively con-

                 fined to the eastern side of the roadway. A review of the

                 aerial topographic maps along Dog Track Road indicates a

                 significant water surface level change from one side of the

                                           5-4

                 roadway to the other. This phenomenon can best be explained

                 by analysis of the soil map, Figure 2-6. On the west side

                 of Dog Track Road, the upland area surrounding Bridge Creek,

                 consists of well drained soils with depth to the water table

                 of ten feet or more. These soils are confined to a relati-

                 vely small area, but the hydrology associated with these

                 soils is significant since no significant flooding problems

                 were identified in this area, even through a  number of resi-

                 dences are located there. Hence; the east side of Dog Track

                 Road is in part experiencing more problems than the west

                 side due to the predominant soils found there.

                 Investigation reveals that the level of flooding occurring

                 along Dog Track Road and U.S. 98 is primarily associated

                 with inadequate longitudinal conveyance and undersized

                 culverts under the roadways. This is not to imply that

                 these roadways did not have proper drainage design. Many of

                 the parcels adjoining the roadways are low and preventing

                 these lots from flooding would be difficult, however, both

                 roadways do not have the capability of adequately inter-

                 cepting and transporting stormwater prior to significant

                 flooding occurring. The installation of undersized side

                 drain culverts along both roadways has compounded the

                 problem.

                 Problems occurring along Aileron Drive and other streets in

                                           5-5

                the area can be attributed to not having a positive outlet

                for stormwater. There are.swamp areas north   and south of

                Aileron that fill up during heavy rains. Due to the minimal

                duration difference between the lots on Aileron and these

                low areas, stormwater tends to accumulate and drain off very

                slowly through t hese low areas that drain from east to west.

                There was only one location identified that experiences

                structural flooding. This flooding occurs to   the first

                floors of several townhomes recently constructed off U.S. 98

                approximately 500-600 feet west  of Aileron Drive and U.S.

                98.

                This flooding appears to be associated with the fact that

                the townhomes are constructed in a depression with no posi-

                tive outlet for stormwater. The units were constructed just

                above natural grade. There are four or five residences

                along Dog Track Road that experience severe yard flooding

                with water to within a few inches of entering their resi-

                dence, but to this point, no structural flooding has been

                identified.

                Two alternatives have been developed to address the worst

                flooding problems in the basin. One complication that deve-

                loped.in dealing with problem areas in the study area is the

                solutions developed must consider impacts outside the study

                                            5-6

                area. There are existing problems occurring on the north

                side of U.S. 96 and any solution to solving problems in the

                study area must not impact the area north of U.S. 98. Con-

                sideration was also given to existing development on the

                west side of Dog Track Road. Both alternatives developed

                consider and minimize downstream impacts.

                Alternative No. 1 for the Bridge Creek Basin is shown on

                Figure 5-1. This alternative takes a conveyance oriented

                approach to solve the problems. It involves upgrading all

                side drains on U.S. 98 from Blue Angel Parkway to a point

                600 feet west of Aileron Drive at U.S. 98. Also, new cross

                drain culverts under U.S. 98 at Skyhawk Drive are proposed.

                Two additional culverts will be placed a lower elevation

                than the existing 36" R.C.P. under U.S. 98, 600 feet west of

                Aileron. To accommodate this increase in flow north of 98,

                and to insure that peak rates downstream are held at or

                below existing levels, a 35 ac. (11 5.7 ac-ft.) stormwater.,
                detention/treatment facility will not only control peak

                rates of discharge, but will also provide pollutant removal

                and water quality enhancement.

                New culverts.are proposed under Ferguson Field to

                reestablish-the natural direction of water flow. Because

                stormwater has no positive outfall, a ditch has been

                constructed that takes the stormwater to U.S. 98. This com-

                                           5-7

                pounds the problems along U.S. 98.    Therefore, it is recom-

                mended that this ditch be filled in  when improvements are

                made west of Ferguson Field that will allow positive

                drainage to the west. It will still be necessary to

                construct a shallow swale to U.S. 98 along the east side of

                Ferguson Field past the subbasin divide shown on Figure 5-1.

                Flow conveyance improvements are proposed from the outlet of

                these culverts under Ferguson Field all the way west to Dog

                Track Road. This construction will basically follow the

                existing low area approximately 300 feet south of Aileron

                Drive. At Dog Track Road and Aileron Drive, new culverts

                constructed at a lower elevation than existing culverts will

                be required. Just east of Dog Track Road and Aileron Drive,

                a 10.5 acre stormwater treatment facility is proposed whi ch

                treats the first inch of runoff from the entire upstream

                contributing drainage area prior to discharging to the west

                side of Dog Track Road. This facility is proposed to pro-

                vide stormwater treatment commensurate with the level of

                treatment provided by the natural system.

                On the west side of Dog Track Road, due to easement restric-

                tions, it will be necessary to construct a paved ditch from

                Dog Track Road almost to Bridge Creek. This will make it

                possible to fit the ditch section in the fifty (50) foot

                easement and still convey the increased discharge from under

                Dog Track Road.

                The total cost to implement this alternative is estimated at

                3.9 million dollars. This includes easement purchases,

                engineering and administrative costs, and a twenty percent

                contingency. The itemized cost tabulation for this alter-

                native is shown on Table 5-1.

                Alternative No. 2 for the Bridge Creek Basin is more storage

                oriented than Alternate No. 1 and does not involve any new

                construction under U.S. 98.

                A large channel on the south side of U.S. 98-is proposed and

                all side drains will be significantly enlarged. Existing

                cross drains under U.S. 98 will remain. These improvements

                are indicated on Figure 5-2.

                A large stormwater detention facility is proposed in

                Subbasin S. Positive gradient  to this facilit'y will.be

                maintained by constructing a channel to the large private

                lake located near the southeast corner of the intersection

                of Dog Track Road and U.S. 98. The maintained level in this

                lake, based on inspection of aerial topographic maps is

                somewhere around 10.0 F.M.S.L. Constructing a wide flat

                channel to a point near this lake will allow the storage

                level fluctuation needed in the proposed detention facility,

                and still provide a positive gradient for the channel along

                U.S. 98.

                                           5_9

                 It is anticipated that the proposed detention facility will

                 not increase discharge rates to the private lake above what

                 is existing now. Overflow discharge for the facility will

                 be through the 2-30" culverts under U.S. 98, while normal

                 flows will be directed west through the private,lake.

                 Another detention facility located in subbasin No. 5 east of

                 Ferguson Field will store and attenuate runoff for this area

                 and direct any discharge out to U.S. 98. However, the rate

                 of discharge from this area shall be significantly reduced.

                 Construction along Dog Track Road is limited to a new low

                 head pipe cross drain just south of the existing 2" x 8" box

                 culvert. This cross drain must be turned north, just west

                 of Dog Track Road and carried to the discharge point of the

                 2' x 8' box culvert located just south of the main entrance

                 to the Greyhound racing track. This construction feature is

                 the same for both alternates 1 and 2. It is anticipated

                 that some regrading of existing ditches on the east side 6 ,f

                 Dog Track Road in the vicinity of the new cross drain will

                 be required to direct stormwater to the new culvert.

                 Other construction common to both alternates involves the

                 construction of a large channel n Subbasins 12 and 13 which

                 will direct runoff to the existing triple three (3) foot by

                 eight (8) foot box culverts under Dog Track Road.. This

                                           5-10

                channel will prevent the accumulation of large volumes of

                stormwater along the roadway by interception of the runoff

                prior to reaching roadside ditches.

                The cost for alternate two (2) is estimated at 3.5 million

                dollars and includes easement acquisition, engineering and

                administrative and anticipated maintenance costs.

                Maintenance costs were calculated by estimating annual main-

                tenance costs at current dollar value. The present worth of

                these annual costs were calculated over a twenty-five (25)

                year period at eight (8) percent interest. This present

                worth maintenance cost is included in the capital cost for

                each alternate. An itemized cost tabulation for this alter-

                nate is shown on Table 5-2.

                As stated at the beginning of this section, alternatives are

                evaluated utilizing a point system to indicate performance

                in five different categories. The points assigned to each

                                                                           A
                category for the two alternates considered in the Bridge

                Creek Basin are shown on Table 5-3.

                Based on this evaluation, the preferr ed alternate is the

                second alternative, which is the storage oriented solution.

                The evaluation points totals between the two alternates is

                so close that slight changes in estimated costs could make

                alternate No. 1 the preferred alternative under this eva-

                 luation scheme. This is  entirely possible since land costs

                 constitute a considerable portion of the total cost  and land.

                 prices fluctuate dramatically depending on geographic loca-

                 tion, the economy, etc. Land  costs used in the estimates

                 are based on current market listings for a small sample of

                 the lots in the area and fluctuate radically with   geographic

                 location. For this reasonf it is apparent that either

                 alternate could be selected.

                 The recommended alternative, however, is alternate No. 2.

                 It does not offer quite the level of service as alternate

                 No. 1, but avoids the possibility of impacting the area

                 north of the study area.  The use of the large area adjacent

                 to U.S. 98 to construct  the detention facility may be a

                 difficult feature to implement, and problems may occur in

                 implementing the construction of the drainage channel toward

                 the private lake at the southeast corner of U.S. 98 and Dog

                 Track Road.

                 If this situation does occur, it may still be possible to

                 implement alternate No. 2 by expanding the detention faci-

                 lity and relying solely on pumped discharge to another loca-

                 tion. The storage volume required would probably be higher

                 and no suitable pump discharge point exists nearby. Pump

                 storage has been considered in the Bayou Grande Headwaters

                 Basin discussed in Section 5.2.

                                           5-12

                If problems do develop in the implementation of alternate

                No. 2, then alternate No. 1 may be pursued.

                Neither alternative is expected to have any lasting impact

                on the environment. In fact, with the proposed stormwater

                treatment facilities, there should be some improvement in

                water quality. The proposed channels.are large enough and

                have such flat side slopes and longitudinal slopes that

                veloci ties will be very low and erosion minimal. These

                channels should provide a level of stormwater treatment com-

                parable to the natural drainageways existing.

                                          5-13

                                                                                                                                                                                                                          AREA FOR STORAGE, Aw- - 3&0 Ar-
                                                                                                                                                                                                                          DEPTH FOR STORAGE - 15 ft.
                                                                                                                                                                                                                          STORAGE VoLL"                                    35 Ac. STORMWA
                                                                                                                                                                                                                          P*OVM - 11&7 AC ft.                              DETENTION FACIIJ

                                                                                                                                                                                                                                                                         400  L.F. 10' 81W PAV   ED DI
                                                                                                                                                                                                                                                                         2:1 &S. PAVED TO A DEPTH
                                                                                                                                                                                                    *--?OONST. 2150 LF.                                                  OF &S' AWL DEPTH OF
                                                                                                                                                                                                            e/W PAVED
                                                                                                                                                                                                        DITCH W1 ZI                                                      DITCH - 4,5'
                                                                                                                                                                                                                                                                         EASEMENT NOTH REOUIRM

                                                                                                                                                                                                                                       INSTALL NEW CLI   LVERTS
                                                                                                                                                            INSTALL (2) 3r R.C.P.
                                                                                                                                                            IN ADDITION  TO                                                            miN. UTECTIVE FLOw
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                                                                                                                                         UPGRADE AND ENLARGE DOSTING
                                                                              ow. rx Ir Itca                                             DITICHS TO 2W
                                                                                                                                         3:1 &&                        10
                                                                                                            40                                                                                                                               400,

                                                                                                                                                                                                                                            ,144

                                                                                                                                                           so

                                              'LE.GEND

                                              BASIN BOUNDARY
                                              PROPOSED DRAINAGE DITCH
                                              EXISTING DRAINAGE CULVERT
                               'BA            BOTTOM WIDTH OF                      PROPOSED DITCH
                                S.S           SIDE SLOPE OF PROPOSED DITCH
                                              DRAINAGE FLOW ARROW

                                                           TABLE 5-1

                                                       BRIDGE CREEK BASIN
                                                 COST ESTIMATE-ALTERNATE NO. 1                      page 1 of 3

                  STORMWATER FACILITY

                  ITEM                       QUANTITY            UNITS        UNIT PRICE          SUB-TOTAL

                  NORTH OF 98

                  Pond Excavation            106,480             C.Y.                4.50         .480,000.00
                  Berm Fill (Clay              4,550             C.Y.                6.00         27,300.00
                  500 Stabilization          144,000             S.F.                0.20         28,800.00
                  Flow Control Struct       LUMP SUM                                              10,000.00
                  Paved Ditches                1-,500            S.Y.               20.00         190,000.00
                  Easements                       36             A.C.           15,000.00         540,000.00

                                                                                 Subtotal      $1,276,lbo-00

                  SUBBASIN #2 and #3

                  Upgrade Culverts -
                      42" R.C.P.                300              L.F.               66.00         20,000.00
                     (Blue Angel Parkway & 98)
                  Upgrade Culverts
                      42" R.C.P
                     H Cessna Dr.)              120              L.F.               66.00           8,000.00
                  New Culverts Under
                      48" R.C.P.
                     (U.S. 98 @ Skyhawk)        160              L.F.               75.00         12,000.00
                  2 - 30" Culverts Under
                      30" R.C.P. (Ferguson
                      Field @ U.S. 98)          500              L.F.               45.00         22,500.00
                  Upgrade Culverts
                      36" R.C.P. (Aileron
                      & 98)                     120              L.F.               50.00           6,000.00
                  Add Two Culverts - 36"
                      Under 98, 500
                      w. Aileron                160              L.F.               50.00           8,000.00
                  Ditch Excav ation           10,000             C.Y.                5.00         50,000.00,

                                                                  TABLE 5-1

                                                             BRIDGE CREEK BASIN
                                                      COST ESTIMATE-ALTERNATE NO. 1                             Page 2 of 3

                   STORMWATER FACILITY

                   ITEM                           QUANTITY             UNITS           UNIT PRICE            SUB-TOTAL

                   Easements (20' Add-
                        itional! R/W)                1.4                A.C.             50,000.00           70,000.00
                   Grassing                      102,000                S.F.                  0.06             6,000.00

                   SUBBASIN #5

                   Channel Excavation             13,000                C.Y.                  5.00           65,000.00
                   4' X 8" R.C.B. @
                        Ferguson Field               250                L.F.                360.00           90,000.00
                   Grassing                      137,500                S.F.                  0.*06            8,000.00
        Ul
                                                                                          Subtotal           365,500.00
        _j         SUBBASIN #7

                   Ditch Excavation                 3,000               C.Y.                  5.00           40,000.00
                   New Culverts @ Rudder
                        Lane 43" X 68"
                        R.C.P.E.                     120                L.F.                147.00           17,600.00
                   Grassing                                             S.F.                  0.06             4,500.00
                   Headwalls                             2              Ea.               2,000.00             4,000.00

                   SUBBASIN #11

                   Replace Driveway 48" X 76"
                        Culverts     Private
                        Drives                       200                L.F.                178.00           35,600.00
                   Ditch Excavation                 8,200               C.Y.                  5.00           41,000.00
                   Pond Excavation                60,000                C.Y.                  4.50           270,000.00
                   New Culverts @ Aileron
                        & Dog Track Road
                        5' X 10' R.C.B.              110                L.F.                500.00           55,000.00
                   Grassing                       93,100                S.F.                  0.06             5,600.00

                                                                  TABLE 5-1

                                                             BRIDGE CREEK BASIN
                                                      COST ESTIMATE-ALTERNATE NO. 1                            Page 3 of 3

                   STORMWATER FACILITY

                   ITEM                          QUANTITY              UNITS           UNIT PRICE            SUB-TOTAL

                   Plant Perimeter of
                        Pond Wetland Species 28,000                     S.F.                   0.50          14,000.00
                   Paved DitcE West
                        of Dog Track Road          5,900                S.Y.                  20.00         118,000.00
                   Headwalls                            4               Ea.              2,000.00              8,000.00

                   SUBBASIN #9 & #10

                   Purchase Natural
                        Storage Areas                  33               A.C.             8,000.00           264,000.00
                   38"  X 60" Culvert
       Ln               Under Dog Track & West
                        Side of Dog Track             600               L.F.                 120.00          72,000.00
       co          Junction Structure                   1               Ea.              2,500.00              2,500.00
                   Headwalls                            I               Ea.              2,000.00             2,000.00_

                                                                                         Subtotal           953,800.00

                   SUBBASIN #12 & #13

                   35' BW Channel
                        Excavation                 16,000               C.y.                   5.00          80,000.00
                   Grassing                      138,000                SI.F.                  0.06          .8,300.00
                   Easements                          4.0               A.C.             8,000.00            32,000-00

                                                                                         Subtotal.          120,300.00

                   MAINTENANCE
                        (PW Over 25 Yr. Per)
                        (All Subbasins)         LUMP SUM                                                    240,000.00
                                                                                              TOTAL        2.,956,000.00.
                                                           + 10%- ENGINEERING & ADMINISTRATION              295,000.00
                                                                             + 20% CONTINGENCIES,           650,000.00

                                                                                      GRAND TOTAL         $3,901,000.00

                                                                 TABLE 5-2

                                                             BRIDGE CREEK BASIN
                                                      COST ESTIMATE-ALTERNATE NO. 2                            Page I of 3

                   ITEM                          QUANTITY              UNITS          UNIT PRICE             SUB-TOTAL

                   SUBBASIN #2

                   42" R.C.P.                        300               L.F.           $      66.00          $19  800.00
                   Concrete Headwall,                   2              Ea.               2,000.00              4,000.00

                                                                                         Subtotal           $23,8ob.oo

                   SUBBASIN #3

                   Channel Excavation             20,500               C.Y.                  5.00           102,500.00
        Qn         42"  Culverts @ Cessna            120               L.F.                  66.00             7,900.00
                   38"  X 60" Culverts
                        @ Skyhawk                    120               L.F.                 118.00           14,200-00
                   43"  X 68" Culvert @
                        Ferguson Field               460               L.F.                 147.00           67,600.bo
                   43"  X 68" Culverts
                        @ Algeron                    120               L.F.                 147.00           17,600.00
                   Channell Grassing             175,000               S.F.                  0.06            10,500.00
                   Easements                         2.4               A.C.              50,000.00          120,000.00

                                                                                         Subtotal          $340,300-00

                   SUBBASIN #5

                   Pond Excavation                67,700               C.Y.                  4.50           305,000-00
                   Grassing                      609,840               S.F.                  0.06            36,500-00
                   Outflow Control
                        Structure                       1              Ea.               5,000.00              5,000.00
                   Easement                          14.0              A.C.              8,000.00           112,000-00

                                                                                         Subtotal          $458,500.00

                                                                 TABLE 5-2

                                                            BRIDGE CREEK BASIN
                                                     COST ESTIMATE-ALTERNATE NO. 2                            Page 2 of 3

                   ITEM                          QUANTITY             UNITS          UNIT PRICE             SUB-TOTAL

                   SUBBASIN #6 & #8

                   Channel Excavation            19,800                C.Y.                  5.00           99'.000.00
                   Pond Excavation               96,800                C.Y.                  4.50         @435,600.00
                   Flow Control Structure               1              Ea.              10,000.00           10,000.00
                   Easements                        25.5               A.C.             35,000.00          892,500-00

                                                                                        Subtotal        $1,437,100.00

                   SUBBASIN #11

                   Ditch Excavation                3,100               C.Y.                  5.00           15,500-00
                   Grassing                      57,200                S.F.                  0.06            3,400-00
                   Easements                         1.8               A.C.             8,000.00            14,400.00-

                                                                                        Subtotal           $33,300-00

                   SUBBASINS #9.& #10

                   38" X 60" R.C.P.E.                660               L.F.                117.63           77,600-00
                   Junction Struct.                     1              Ea.              2,500.00             2,500.00
                   Headwalls                            2              Ea.              2,000.00             4,000.00
                   Grassing                      13,200                S.F.                  0.06               800.00

                                                                                        Subtotal           $84,900-00

                   SUBBASINS #12 & #13

                   Ditch Excavation              13,700                C.Y.                  5.00           68,500-00
                   Grassing                      118,800               S.F.                  0.06            7,100-00
                   Easements                         3.8               A;C.             8,000.00            30,400-00-

                                                                                        Subtotal           106,000-00,

                                                            TABLE 5-2

                                                        BRIDGE CREEK BASIN
                                                  COST ESTIMATE-ALTERNATE NO. 2                       Page 3 of 3

                  ITEM                       QUANTITY            UNITS          UNIT PRICE           SUB-TOTAL

                  MAINTENANCE               Lump Sum                              Subtotal          141,600.00

                                                                                   TOTAL          2,6251500.00
                                                                     + 10% ENGINEERING              262,500.00
                                                                     20% CONTINGENCIES              577,600.00

                                                                                   TOTAL         $3,465,600.00

                                          TABLE 5-3

                                ALTER NATIVE EVALUATION FOR THE
                                      BRIDGE CREEK BASIN

                                                 Alternate         Alternate
                                                   No. 1             No. 2

                 Economic Impact                     3                 4

                 Environmental Evaluation            3                 3

                 Level of Service Provided           4                 3

                 Downstream Impacts                  3                 4

                 Human Issues Evaluation            3.6               3.6

                 TOTAL                             16.6              17.6

                                           5-22

                5.2 BAYOU GRANDE HEADWATERS AND BAYOU GRANDE BASIN

                The Bayou Grande Headwaters is the second largest    defined

                basin in the study area. It comprises 6.24 square miles or

                3900 acres. This basin is very similar to the Bridge Creek

                Basin, not only in size, but it is also hydrologically simi-

                lar. Like   the Bridge Creek Basin, developmment is sparse

                and is limited to isolated'concentrations of residential

                development and distantly spaced singular commercial uses.

                In fact, this basin is more rural than the Bridge Creek

                Basin with the only sizable residential concentration being

                the Pleasant Grove community.

                The Bayou Grande Basin consists of that area cont   ributing

                drainage laterally along the length of the Bayou Grande to

                the study basin limits. Commercial   and residential develop-

                ment in this basin is much more intense than either Bridge

                Creek or the Bayou Grande Basin. This basin has a drainage

                area of 3.94 square miles or approximately 2500 acres. it.,

                differs hydrologically from the headwaters in that the

                terrain is moderately sloped, not level. With the excep-

                tion of a large constructed drainage ditch draining a por-

                tion of Sherman Field, there are no sizable concentrations

                of stormwater, at least not in comparison to Bridge Creek or

                the Bayou Grande Headwaters.

                                            5-23

                tely for the north and south portions of the basin.

                Since the only identified problem in the Bayou Grande Basin

                is just east of Old Gulf Beach Highway in the Pleasant Grove

                area, alternative evaluation for this basin will be included

                with the Pleasant Grove evaluation in the Bayou Grande

                Headwaters.

                5.2.1 BAYOU GRANDE HEADWATERS - NORTH

                The area experiencing the most drainage problems in the

                nor thern portion of the basin lies on the east side of Dog

                Track Road and extends north and south approximately 2500

                3000 feet of the intersection of Dog Track Road and Blue

                Angel Parkway. Most of this area is low when compared to

                the roadway elevations and considerable acreage becomes

                inundated during heavy rain s.

                The area north of Blue Angel Parkway and east of Dog Track

                Road has no positive outlet due to the lack of a culvert

                under Dog Track Road. Although, two 30-inch culverts exist

                under Blue Angel Parkway, on the east side of the intersec-

                tion with Dog Track Road, these culverts were not designed

                to carry the stormwater from the northeast corner of Dog

                Track Road and Blue Angel Parkway. Hence, a substantial

                area has no drainage outlet at an elevation below flooding.

                The drainage area involved is somewhat difficult to deter-

                                           5-24

                mine due  to the inability to evaluate the effect of the

                culverts  under Blue Angel Parkway which have no positive

                outlet, with the exception  of the 30 inch culverts at the

                intersection mentioned previously    Topographic aerials

                indicate that three sets of culverts to the east of the

                intersection should direct some stormwater from Subbasin 15

                north to Subbasin 16 as shown on Figure 5-3.   However, the

                actual percentage has not been determined.

                In any event, it is estimated that approximately 300 acres

                total drainage area north and east of the intersection has

                no positive outlet. For this reason, when flooding does

                occur, the duration is on the order of five to six days,

                which is intolerable.

                On the south side of the intersection, significant yard

                flooding on the east side of Dog Track Road occurs.

                However, due to positive drainage through culverts under Dog

                Track Road, the flooding is of limited duration. Though

                several residences.experience severe yard flooding, much of

                the acreage inundated is cultivated range land.

                Three alternatives were developed to address flooding in

                this area. The first alternative involved improvements in

                the conveyance of stormwater from east to west under Dog

                Track Road. Also, ditches are proposed which will intercept

                stormwater before it gets to the roadway and direct it more

                                            5-25

                 efficiently to the existing culvert'crossing locations.

                 These improvements are shown on Figure 5-3.

                 New culverts are proposed under Dog Track Road approximately

                 1250 feet northwest of its intersection with Blue Angel

                 Parkway. Calculations indicate that an effective flow area

                 of sixty (60) square feet would be required to safely pass

                 the 25 year storm under the roadway. However, there are

                 only three 36 inch culverts downstream under Blue Angel

                 Parkway and unless these culverts are replaced, the capacity

                 under Dog Trac k Road would be wasted. For this reason, a

                 lower level of service at this location would appear to be

                 an acceptable solution and three 36 inch culverts are pro-

                 posed under Dog Track Road.

                 On the south side of the intersection, interceptor ditches

                 are proposed in Subbasins 15 and 17. In Subbasin-15, the

                 existing culverts under Dog Track Road are left intapt.
                 However, driveway culverts must be replaced, since they ac At

                 to restrict flow.

                 In Subbasin 17, a large ditch is proposed along the rear

                 property lines of those parcels abutting Dog Track Road.

                 This ditch will intercept much of the stormwater from the

                 east and direct it perpendicular to the box culvert under

                 Dog Track Road approximately 2600 feet south of the inter-

                                            5-26

                 section with Blue Angel Parkway. At this location, it will

                 be necessary to significantly increase the culvert size

                 under Dog Track Road. Preliminary estimates show the need

                 to construct two 4 foot X 8 foot box culverts in addition to

                 the ex isting culvert of the same size.

                 Cost estimates to make these 'improvements are shown on Table

                 5-4. The total cost to implement these improvements is

                 approximately $684,000.00 or about $937.00 per acre drained.

                 The second alternate considered for this area involves the

                 construction of two large stormwater storage facilities, one

                 with gravity discharge, the other with pumped discharge.

                 The improvemments proposed as part of this alternate are

                 shown on Figure 5-4. A twenty-one acre pumped storage area

                 is required northeast of the intersection on the east side

                 of Dog Track Road. The large size required is due to the

                 large volume of runoff for the 25 year-24 hour design stor.p.

                 Since pumping rates are small in comparison to gravity

                 discharges, the large storage area is needed to prevent

                 flooding of the residential lots along Dog Track Road. The

                 pumping station proposed would consist of two 5,000 gpm

                 pumps, along with one 5,000 gpm pump on standby. Since

                 maintained water levels in the pump storage facility would

                 have to be below existing groundwater levels, it would be

                                            5-27

                 necessary to have a smaller 500 gpm pump to handle the

                 constant groundwater inflow into the facility. A rather

                 large 24" diameter force main would be required to handle

                 the peak pump discharges. The large size was selected to

                 reduce the total dynamic head by minimizing friction losses

                 in the line.

                 Also, proposed under Alternate 2 is a large stormwater

                 detention facili ty on the east side of Dog Track Road and

                 south of the intersection with Blue Angel Parkway. This

                 facility will store stormwater prior to releasing it into a

                 channel constructed perpendicular to Dog Track Road. With

                 this controlled release of stormwater, enlarging the

                 culverts under Dog Track Road becomes unnecessary.

                 Cost estimates for this alternate are shown on Table 5-5.

                 The total cost to implement this alternate is expected to be

                 in excess of 2.3 million dollars or $3200/acre.   This is a

                                                                            A
                 significantly higher cost than Alternate 1.

                 It is expected that Alternate 2, however, will provide a

                 superior level of service, particularly for the area north

                 of Blue Angel Parkway.

                 The third alternate is actually a variation of Alternate 2.

                 In this alternate, the excavated storage facility on the

                 north side of the intersection is reduced to just a small

                sump area, one acre in size. Flooding in the northeast

                corner would still continue at a reduced level and have a

                much shorter duration. This is probably a good choice,

                since only five or six parcels are involved, and no struc-

                tural flooding has been identified. If the pumped discharge

                remains, but constructed.storage is virtually eliminated,

                then the total cost to implement Alternate 3 would be 1.24

                million dollars or approximately $1700/ac.

                This cost is still 80 percent higher than Alternate 1 but

                only 53 percent of the cost of Alternate 2.

                The various alternatives for this area have been evaluated

                in five categories as shown in Table 5-6. Note that based..

                on this evaluation, Alternate 2, the most costly alternative

                would be the preferred alternate. However, this is based on

                honest objective merits assigned to very general categories.

                For this reason, it is felt that th e evaluation procedures

                in this case, results in an erroneous choice for best selec-

                tion. Although economic impacts are evaluated in the proce-

                dure, there is no degree or scale applied to the evaluation

                process, other than the relative cost of an alternate. In

                other words, the procedure does not assign points in the

                economic category based on the actual cost of an alternate,

                but rather, its rank when compared to the other alternates

                                           5-29

                considered. Since Alternate 2 costs almost three and one-

                half times to implement versus Alternate 1, Alternate 1

                should be selected based on economy alone.

                Therefore, the recommended alternative for Bayou Grande

                Headwaters - North, is Alternate 1.

                5.2.2 PLEASANT GROVE

                The Pleasant Grove area is a small upland area on an extre-

                mely level plateau at elevation 17.5 F.M.S.L. to 19.5

                F.M.S.L., surrounded on all sides by slightly lower swamps

                and wetlands. On the south, the South Loop Road follows an

                ill defined ridge separating the Bayou Grande Basin and

                Garcon Swamp. The plateau on the west side of Blue Angel

                Parkway is roughly 1500 to 2000 feet wide and slopes gra-

                dually toward the extreme western tip of Bayou Grande.

                This area has chronically experienced drainage problems

                through the years. However, most long time residents in the

                area indicate that conditions have deteriorated over the

                past few years. The area soils have somewhat poor to very

                poor infiltration capability and the water table is only a

                foot or two below ground level most of the year.

                Most problems identified have been related to severe yard

                flooding and minor street flooding. However, at least two

                                           5-30

                locations have experienced minor damages due to water entry

                into their residence.

                The locations that these problems have been identified is

                shown on Figure 3-1, in Section 3 of this report.

                Also identified and addressed here is street and yard

                flooding occurring on Robertson Road in the Bayou Grande*

                Basin.

                Two alternatives were developed for the Pleasant Grove and

                Robertson Road area. These alternates are based on slightly

                different approaches to dealing with the problems in the

                area. The second alternate introduces the use of

                underdrains and pumped storage, whereas,-the first alternate

                relys strictly on channelization and conveyance improve-

                ments.

                The first alternate is actually based on a master plan for

                the Pleasant Grove area developed by Escambia County

                Engineering. Since portions of this plan have been imple-

                mented, it is expeditious to utilize those improvements

                made, to the extent possible.

                Most of the changes proposed are related to expanded ditch

                sections and associated easement widths. However, two areas

                were identified that are still experiencing problems after

                                           5-31

                the improvements proposed in the master plan were imple-

                mented.

                The proposed improvements for Alternate 1 are shown on

                Figure 5-5. These improvements are numbered and annotated

                on the Figure... The changes proposed from the Escambia

                County Master Plan other than channel and  easement sizes are

                enlarging a 24 inch R.C.P. to 30 inches under Etheridge

                Drive, and placing it such that it discharges do wnstream of

                the existing residential driveway on the north side of

                Etheridge. It is also recommended that the roadside ditch

                be paved from the discharge point of the proposed 30"

                culvert to the large drainage ditch which flows north from

                Etheridge Drive to a  channel flowing west to east under the

                bridge on Blue Angel  Parkway to Bayou.Grande- The other

                major change is the addition of a constructed channel north

                from Sidney Road to Bayou Grande (Reference Number 24,

                Figure 5-5). It is expected that there will be environmen-

                tal concerns associated with this construction, therefore a

                constructed treatment facility is proposed adjacent to Bayou

                Grande to treat runoff in accordance with F.A.C. 17-25 for

                the contributing drainage area.

                Cost estimates for Alternative 1 are shown on Table 5-7.

                The implementation cost for this alternate is $797,000 or

                approximately $1,000/acre drained.

                                           5-32

                This cost includes the construction of a roadside channel

                with outfall ditches and culverts on Robertson Road

                (Reference Numbers 35 thru 38, Figure 5-5). The roadside

                ditch proposed intercepts flow on the east side of Robertson

                Road and channelizes it to two proposed culvert locations,

                where outfall ditches to the Navy ditch draining Sherman

                Field will be constructed.

                The second alternate for Pleasant Grove departs from the

                partially implemented Escambia County Master Plan by pro-

                viding pumped storage areas adjacent to and north of South

                Loop Road on both sides of Blue Angel Parkway. Subsequent

                discharge from these facilities will be directed through the

                thirty foot F.D.O.T. easement running northeast from Blue

                Angel Parkway. These facilities are shown on Figure 5-6.

                The concept here is to reduce the area contributing drainage

                to the residents on North Loop Road while also lowering the

                water table elevation in the vicinity of the South Loop

                Road. To aid in this, perforated underdrains along the road

                right-of-way is proposed. Before this feature is imple-

                mented, further study of subsurface conditions is necessary.

                To accomplish a satisfactory evacuation of stored stormwater

                following a storm event, the total station pump capacity

                should be at least 4000 gpm. It is anticipated that desired

                                           5-33

                maintenance of water  levels can be obtained by utilizing a

                smaller pump with capaci ty in the range of 500 - 800 gpm

                under the expected operating head conditions which will be

                less than  20 feet total dynamic head.

                Both pump storage facilities are about the same size with

                comparable pump capacities.

                The cost to implement Alternate 2 is estimated at 1.5

                million dollars or approximately $1,781/acre drained.

                A comparison of the two alternates reveals that Alternate 2

                is preferable in three out of the five evaluation cate-

                gories, hence, it achieved the hig hest point total in,the

                evaluation procedure. However, much of Alternate I is

                already in place and it is the least costly alternate.

                Alternate 2 comes closest to emulating natural drainage

                conditions that occurred prior to construction of Blue Angel

                Parkway and it is expected that some lowering of the water

                table on South Loop Road is possible.

                If funding is available, it is recommended that Alternate 2

                be implemented, othewise, Alternate I will accomplish many

                of the same objectives, at a much lower cost.

                                           5-34

                                                  4000                                                                                E)(IST (2) 24" R.C.P..
                                                                          04b
                                                                                     40,
                                 000  .1olf                        CONST. 25' S/W DITCH

                                                                                                                                                                                loo

                                                     41,                                                                                                            to

                                                                                                                                                        loo
                                                                              MAINTAIN                                                              to
                                                                              NATURAL
                                                                              STORAGE
                                                INSTALL
                                                          F.W.

                                                            sm.            ILQP.                            AW- I )EIPTH

                                                                                                     REPLACE E)OST. DRV4WAY
                                                                                                     CULVERTS W/ 4@x lcr
                                                             3-3r R.C.P                              BOX CULVER`rS
                                                                                                                                                    CONST. 3w BW 011CH
                                                                                                                                                    W/3c 1 Ss.
                                                                         CONST.           WlDTH
                                                                                ID' 81U.                                                            AVQ. DEPTH -i
                                                                         PAVED CHANNEL                                                              EASEMENT WIDTH
                                                                                                                                                     'QUIRED
                                                                         W/2:1 S.S.                                                                             711.
                                                                                                            (l)-41r (1)4A Ir R.CjL
                                                                                                            m
                                                                                                               REMAIN

                                                                                            ADD TWO (2)
                                                                                            41A Ir R.C.9L
                                                                                                                                                    dowo as am*
                                                                                                                     sawassous

                                                                                                                                                                                                                                                         BAY

                                                                                woo
                                                                           -SO
                                                                         Ole
                                                                      to                                            10
                                                                                                                 4e

                                         Sol
                                                                                                    INS
                                                    Oka= aw woo

                               100

                                 -po                                                       '040
                                                                                       to
                                                 C2
                                              x                                   to to

                                  REQUUtED (4) 5= GLPJA.
                                  PUMPS IN PARALLEL                        to
                                                                         400

                                                          EXISTWO
                                                         (2) W R.C.P.

                                                                                 cam   O/W
                                                                                 MTM AT.

                                                                                    orw
                                                    (3) W
                                                     q
                                                        E)WnNO
                                             4
                                                        41r Rr-P.
                                                         R.C.P.

                                                                     =W. 2W D/W 04"WEL
                                                                     AT &I &&
                                                                     AVQ DEPM f
                                                                                               as SIX
                                         A.4                                         SIMMONS
                                                                     Saloom ma moo so small

                                                                                                               BA"Y

                                                           TABLE 5-4

                                                         COST ESTIMATE
                                                       ALTERNATE NO. 1                             Page 1 of 2
                                        BAYOU GRANDE HEADWATERS AND BAYOU GRANDE BASIN

                 BAYOU GRANDE HEADWATERS    NORTH
                 SUBBASIN #18

                 ITEM DESCRIPTION            QUANTITY           UNIT             UNIT PRICE          TOTAL

                 Channel Excavation            11,500           C.Y.                 5.00          58,000.00
                 36 In. Culverts Under
                  Dog Track Road                  180           L.F.                 50.00           9,000.00
                 Grassing                     105,000           S.F.                 0.06            6,000.00
                 Easements - Ditch                3.13          AC.              8,000.00          25,000-00
                 Property Purchase
                 Conservation                     15.0          AC.              5,000.00          75,000.00

                                                                                 Subtotal         $173,000.00

                 SUBBASIN #15

                 Channel Excavation              7,500          C.Y.                 5.00          37,500.00
                 Paved Channel                   1,960          S.Y.                 20.00          .39,000.00
                 Replace Driveway
                  Culverts w/41xlO'  R.C.B.         60          L.F.                500.00         30,000.00
                 Grassing                      60,000           S.F.                 0.06            3,500.00
                 Easements                         1.5          AC.              8,000.00          12,000.00

                                                                                 Subtotal         $122,000.00

                 SUBBASIN #17

                 Channel Excavation             23,000          C.Y.                 5.00         $11-5,000.00
                 New Culverts Under Dog
                  Track Road 2-4'x8' R.C.B.        120          L.F.                400.00         48,000.00

                                                              TABLE 5-4

                                                            COST ESTIMATE
                                                           ALTERNATE NO. 1                               Page 1 of 2
                                          BAYOU GRANDE HEADWATERS AND BAYOU GRANDE BASIN

                  BAYOU GRANDE HEADWATERS      NORTH

                  ITEM DESCRIPTION             QUANTITY             UNIT             UNIT PRICE            TOTAL

                  SUBBASIN #17(continued)

                  Grassing                      199,800             S.F.                   0.06          12,000.00
                  Easements                        5.95             AC.               8,000.00           48,000.00

                                                                                      Subtotal          $223,000.00

                                                                                TOTAL (NORTH)            518,000.00
        co                                                 10% ENGINEERING & ADMINISTRATIVE              52,000.00
                                                                         + 20% CONTINGENCIES             114,000.00

                                                                          GRAND TOTAL (NORTH)           $684,000.00

                                                                TABLE 5-5

                                                              COST ESTIMATE
                                                             ALTERNATE NO. 2
                                                    BAYOU GRANDE HEADWATERS      NORTH

                   ITEM DESCRIPTION              QUANTITY             UNIT              UNIT PRICE            TOTAL

                   SUBBASIN #16

                   Excavation - Pump
                        Storage Facility         160,000              C.Y..                 4.00           760,000.00
                   Pumping Station
                        10,000 GPM                       1            Ea.              250,000.00          250,000.00
                   24" Force Main                    2,100            L.F.                  35.00           74,000.00
                   Maintenance and
                        Operating Cost           Lump Sum                                                   60,000.00
                   Channel Excavation             12,000              C.Y.                  5.00            60,000.00
                   Grassing                      200,000              S.F.                  0.05            12,000.00
                   Easements                            24            AC.               5,000.00           .120,000.00

                                                                                        Subtotal         $1,336,000.00

                   SUBBASIN #17

                   Channel Excavation             14,000              C.Y.                  5.00            70,000.00
                   Detention Facility
                        Excavation                48,000              C.Y.                  4.00           192,000.00
                   Control Structure             Lump Sum                                                   10,000.00
                   Grassing                      150,000              S.F.                  0.06              9,000.00
                   Sod (Detention Sides
                        and Berm)                 40,000              S.F.                  0.20              8,000.00
                   Easements                            28            AC.               5,000.00           140,000.00

                                                                                        Subtotal           429,000,00

                                                                                            TOTAL        $1,765,000.00
                                                          + 10% ENGINEERING & ADMINISTRATION               177,000.00
                                                                           + 20% CONTINGENCIES             388,000.00-

                                                                                    GRAND TOTAL          $2,330,000.00

                                            TABLE 5-6

                                      ALTERNATIVE EVALUATION
                                BAYOU GRANDE HEADWATERS      NORTH

                                                Alternate Alternate. Alternate
                                                No. 1       No. 2       No. 3

                 Economic Impact                     4                      3

                 Environmental Evaluation            2          3           3

                 Level of Service Provided           3          4           2

                 Downstream Impacts                  2          3           3

                 Human Issues Evaluation            3.6         4          3.4

                      TOTAL                       14.6        15.0        14.4

                                              5-40

                           LEGEND

                -------    BASIN BOUNDARY                                                     N
                           PROPOSED DRAINAGE DITCH                                         -Ak ,
                           EXISTING ROADS                                                  vw@@lc
                           EXISTING CULVERT                                                   s
                           PROPOSED CULVERT
                  B W:'    BOTTOM WIDTH OF. PROPOSED    DITCH                                  10:00,
                  3:1 S.,S.@'.3. TO. f SIDE SLOPE OF DITCH
                  C.M.P.,  CORRUGATED METAL    PIPE
                  R.C. P.'. REINFORCED CONCRETE   PIPE
                           DRAINAGE  FLOW ARROW

                                                                                        @6

                                                    21
                                                                                    0               5..

                                                          6
                                                               2
                                                                SSIDNE                        6
                                                                 2
                                                                         2.
                                    10
                                                      19
                                                                    2
                                                                                                   8
                .8
                                            12
             .7
                       woo a                            f       3
                                                     13
                            6
                                 51

                                                                                                  an In I= am

           ET)IERIDGE' RD.                                            mm.
                                                    0

                                          +om..
                                  0000         16
                                                                    DRAINAGE ALTERNATE
                                                                             PLEASANT        GROVE

                                                                                                                                                   A. PUMP STORAGE FACILITY
                                                                                                                                                          3' STORAGE OVER 10.0 AC.
                                                     LE'GEND                                                                                              TOP OF STO             .RAGE = 16.0
                                                                                                                                                          BOTTOM OF STORAGE = 13.0,
                               -------               BASIN BOUNDARY
                                                     PROPOSED DRAINAGE                            DITCH                                            B.     PUMP STORAGE FACILITY
                                                     E)aSTING ROADS
                                                     EXISTING CULVERT                                                                                     30 ACRE-FT.
                                                     PROPOSED CULVERT
                                                                                                                                                   @C.    STORMWATER@: PUMP -STATION
                                  B/W                BOTTOM WIDTH OF                        PROPOSED                DITCH
                                  3: 1 S. S.         3' TO 1' SIDE SLOPE 'OF DITCH                                                                      .2 2000 G.P.-M.                   PUMP
                                  C. M. P.           CORRUGATED METAL                           PIPE                                                      _1720.00          G.:P.M.      PUMP        (STANDB.y
                                  R. C. P.           REINFORCED CONCRETE                              PIPE                                                1-800          G.P.M.
                                                     DRAINAGE FLOW ARROW

                                                                                                                                                                                             STORMWATER
                                                                                                                                                                                               TREATMENT
                                                                                                                                                                                                 FACIUTY
                                                                                                                                                                                                          30"   R.C.P

                                                                                                                                                                                                               CURB

                                             looo
                                                                                                           21
                                                                                                                                                                                                                5

                                                                                                                        6,.       2
                                                                                                                                    SIDNEY R                                                                   PA
                                                                                                                                                                                                               IN     R
                                                                                                                                      2

                                                                                              :)3
                                                                         10                                                                                                                 A:
                                                                                                                                                                                                          W   EN   AN
                                                                                                               19
                                                                                                                                                                                                          EXISTING.
                                                                                                                                                                                       A                     18
                                                                                         12
                                                                                                                                                                              A
                      /07                                                                                                           31
                                         .   :, * ...                                                                                                                                 :       ., S

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                                                                      1

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                   Mw Mof                    2
                  0@                                                                                A
                 .0  ETHERIDGE R-6.

                                                                                                                                              38
                                                                             5
                                                                           00    to
                                                                                                                                                                                             I
                                                                                                                                                                                               T   R      A   @R
                                                                                                                                                                                                              T
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                                                                                                                                                                                                  0
                                                                                                                                                                                                 R      -M
                                                                                                                                                                                                 FACIUly

                                                                                                                                                                                                          30    R_(

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                                                                                                                                                                                                                 A
                                                                                                                                                                                                     @PIN

                                                                                                             38                       DRAINAGE ALTERNATE* NO
                                                                                                                                                        PLEASANT. GROVE

                                                                  TABLE 5-7

                                                                COST ESTIMATE
                                                              ALTERNATE NO. 1                                   Page 1 of   4
                                             BAYOU GRANDE HEADWATERS AND BAYOU GRANDE BASIN

                   SOUTH

                   FIGURE REFERENCE             ITEM                                                  UNIT
                        NUMBER              DESCRIPTION            QUANTITY            UNITS          PRICE        TOTAL
                            1            Channel Excavation           1,600            C.Y.            5.00     $ 81000.00
                                         Grassing                   48,000             S.F.            0.06       2,880.00
                                         Easement                      0.60            AC.        8,000.00        4,800.00
                            2            Ditch Paving                   700            S.Y.           20.00      14,000.00
                            3            30" R.C.P.                     100            L.F.           48.00       4,800.00
                                         (Includes Pavement
                                         Replacement)

                            4            24" R.C.P.                       40           L.F.           40.00       1,60-0.00
                            6            Channel Excavation             800            C.Y.            5.00       4,000.00
                                         Grassing                   30,000             S.F.           .0.06       1,800.00
                                         Easement                      0.06            AC.        8,000.00            500.00
                            8            Channel  Excavation          1,900            C.Y.            5.00       9,500.00
                                         Grassing                   35,000             S.F.            0.06       2,000.00
                                         Easement                      0.96            AC.        8,000.00        8,000.00
                            9            Channel Excavation           5,000            C-Y.            5.00      25,000.00
                                         Grassing                   75,000             S.F.            0.06           450.00
                                         Easement                       2.0            AC.        8,000.00       16,000.00
                           10            Channel Excavation           1,900            C.Y.            5.00       9,500.00
                                         Grassing                   22,880             S.F.            0.06      11,400.00
                                         Easement                      0.70            AC.        8,000.00        5,600.00

                                                           TABLE 5-7

                                                         COST ESTIMATE
                                                        ALTERNATE No. 1                             Page 2 of 4
                                        @BAYOU GRANDE HEADWATERS AND BAYOU GRANDE BASIN

                 SOUTH

                 FIGURE REFERENCE          ITEM                                            UNIT
                      NUMBER           DESCRIPTION          QUANTITY          UNITS        PRICE       TOTAL

                        11          Channel Excavation         2,000          C.Y.          5.00     10,000.00
                                    Grassing                 20,000           S.F.          0.06      1,200.00
                                    Easement                   0.60           AC.      8,000.00       4,800.00

                        12          Channel Exc  avation       2,900          C.Y.          5.00     14,500.00
        Ln                          Grassing                 30,600           S.F.          0.06      1,800.00
                                    Easement                     0.8          AC.      8,000.00       6,400.00

                        14          Channel Excavation         4,200          C.Y.          5.00     21,000.00
                                    Grassing                 46,000           S.F.          0.06      3,000.00
                                    Easement                   1.24           AC.      8,000.00      10,000.00

                        16          24" R.C.P.                    40          L.F.         40.00      1,600.00

                        17          Channel Excavation         3,700          C.Y.          5.00     18,500.00
                                    Clearing                     0.9          AC.      2,000.00       1,800.00
                                    Grassing                 37,500           S.F.          0.06      2,250.00
                                    Easement                     0.9          AC.      5,000.00       4,500.00

                        20          36" R.C.P.                     80         L.F.         50.00      4,000.00

                        21          Channel Excavation         5,000          C.Y.          5.00     25,000.00
                                    Grassing                 49,000           S.F.          0.06      3,000.00
                                    Easement                   0.96           AC.      8,000.00       8,000.00

                        22          Channel Excavation         2,500          C.Y.          5.00     12,500.00
                                    Grassing                 47,000           S.F,.         0.06      2,800.00
                                    Easement                   0.50           AC.      8,000.00       4,000.00

                                                                       TABLE 5-7

                                                                    COST ESTIMATE
                                                                   ALTERNATE NO. 1                                      Page 3 of 4
                                                BAYOU GRANDE HEADWATERS AND BAYOU GRANDE BASIN

                    SOUTH

                     FIGURE REFERENCE              ITEM                                                      UNIT.
                         NUMBER                DESCRIPTION              QUANTITY             UNITS           PRICE          TOTAL

                            23             Pond Excavation                13,000              C.Y.            5.00
                                           Landscaping                    Lump Sum                                       15,000.00
                                           Easement                           2.1             AC..       20,000.00       42,000.00

                            24             Channel Excavation              3,300              C.Y.            5.00       16,500.00
                                           Easement                          0.96             AC         20,000.00       19,000.00
                                                                                              S.F.
                                           Grassing                       42,000                              0.06         2,500.00

                            26             36" R.C.P.                           60            L.F.           50,00         3,000.00

                            27             24" R.C.P.                           40            L.F.           40.00         1,600.00

                        28 &   29          Channel   Excavation            1,900              C.Y.            5.00         9,500.00
                                           Grassing                       25,000              S.F.                         1,500.00
                                           Easement                          0.60             AC.         8,000.00         5,000.00

                            30             Channel Excavation              2,000              C.Y.            5.00       10,000.00
                                           Grassing                       32,000              S.F.            0.06         1,900.00

                            31             Channel Excavation              4,300              C.Y.            5.00         7,000.00
                                           Grassing                       87,000              S.F.            0.06         5,000.00
                                           Easements                          2.2             AC.         8,000.00       18,000.00

                            33             18" R.C.P.@                          40            L.F.           30.00         1,200.00

                            35             Channel Grading                 1,600              C.Y.            4.00         6,400.00

                            36             Purchase Additional
                                           R/W                               0.32             AC.         8,000.00         3,000.00

                                                                  TABLE 5-7

                                                               COST ESTIMATE
                                                              ALTERNATE NO. 1                                  Page 4 of 4
                                             BAYOU GRANDE HEADWATERS AND BAYOU GRANDE BASIN

                   SOUTH

                   FIGURE REFERENCE            ITEM                                                  UNIT
                        NUMBER             DESCRIPTION             QUANTITY           UNITS          PRICE         TOTAL

                          37            24" R..C.P.                      100           L.F.          40.00        4,000.00

                          38            Channel Excavation            1,000            C.Y.            5.00       5,000.00
                                        Grassing                     20,000            S.F.            0.06       1,200.00
                                        Easements                        0.5           AC.        8,000.00        4,000.00
         Ln

                                        Maintenance                 Lump Sum                                     72,000.00

                                                                                                     TOTAL      604,000.00
                                                                   + 10% ENGINEERING & ADMINISTRATION            60,000.00
                                                                                    + 20% CONTINGENCIES         133,000-00

                                                                                              GRAND TOTAL      $797,000.00

                                           TABLE 5-8

                                     ALTERNATIVE EVALUATION
                                         PLEASANT GROVE
                               BAYOU GRANDE HEADWATERS - SOUTH

                                                 Alternative        Alternative
                                                     One                Two

                 Economic Impact                       4                  1

                 Environmental Evaluation              2                  4

                 Level of Service Provided             3                  3

                 Downstream Impacts                    3                  4

                 Human Issues Evaluation             3.2                3.4

                     TOTAL                          15.2               15.4

                                             5-47

                 5.3 GULF BEACH HIGHWAY

                 The area along Gulf,Beach Highway consists, for the most

                 part, of fairly high ground with elevations ranging between

                 13 feet and 28 feet on the north side of the highway. This

                 area is separated from Garcon Swamp basin by an   ill-defined

                 ridge line located between 600 feet and 2500 feet north of

                 Gulf Beach Highway. The land slopes in a general southerly

                 direction and there are several depressions which retain

                 stormwater. Some of the depressions contain standing water

                 for long periods of time and are mostly in undeveloped areas

                 north of Gulf Beach Highway. There are many other

                 depressions which pond water for fairly short periods of time

                 and have caused varying degrees of flooding on private

                 property.

                 Since the soils are sandy and relativ ely permeable, the

                 runoff from most moderate storms infiltrates the soil and

                 percolates down to the water table. However, there has been

                 some severe street flooding and some structural flooding

                 caused by heavy storms after an extended rainy period. most

                 of the problems have occured on the north side of Gulf Beach

                 Highway. It seems that drainage across Gulf Beach Highway is

                 not adequate to control the runoff which reaches the highway.

                 Water has flowed over the highway on several occasions near

                 most of the existing culvert crossings.

                                             5-48

                 5.3.1 GRAND LAGOON SUBDIVISION

                 The Grand Lagoon subdivision is located on Big Lagoon. it

                 lies to the east of Big Lagoon,State Park and extends north

                 across Gulf Beach Highway. This subdivision has experienced

                 some street flooding and structural flooding in the past.

                 The structural flooding has occured north of the highway and

                 is a result of inadequate drainage capacity.

                 There are several 24-inch culverts which drain south across

                 Gulf Beach Highway. The culvert located near the western end

                 of the subdivision (600 feet west of Ponte Verde Drive)

                 drains into Big Lagoon,State Park. This culvert drains

                 approximately 25 acres of the subdivision and it appears that

                 there has been no maintenance of the downstream ditch in

                 recent years. There is actually no place for the water to go

                 once it flows past the culvert. A possible reason for the

                 lack of maintenance may be the absence of a drainage easement

                 through the State Park. Immediate measures should be taken

                 by Escambia County to obtain an adequate drainage easement

                 and construct an adequate stormwater outfall to provide some

                 temporary relief. Even with proper maintenance of the

                 outfall, the culvert appears to be undersized. The culvert

                 is fairly high with very little cover. This causes water to

                 back up onto private property before it can flow through the

                 culvert. There has been some structural flooding near this

                 culvert and water has crossed over Gulf Beach Highway.

                                            5-49

                 The second culve-rt crossing in Grand Lagoon subdivision is

                 located about-300 feet west of Grand Lagoon Boulevard. This

                 location is approximately 1800 feet east of the previously

                 mentioned crossing. There are two 24-inch culverts about 200

                 feet apart at this location. Stormwater flows through the

                 culvert located closest to Grand Lagoon Boulevard and

                 discharges into a grassed swale located 350 feet south of

                 Gulf Beach Highway. The swale then carries the stormwater

                 about 900 feet to another 24-inch pipe which carries the flow

                 into the lake system of the subdivision. The flow from the

                 second culvert on Gulf Beach Highway runs east along the

                 south side of the highway and into a catch basin where it

                 combines with the flow from,the  first culvert. The combined

                 area drained by these two culverts is approximately 25 acres.

                 The drainage problems associated with these culverts are

                 similar to the problems located to the west. There has been
                 substantial, street and yard flooding north of the highway and

                 at least one residence has been flooded. Again, it seems

                 that the culvert capacity is not adequate to control the

                 runoff.

                 The third culvert crossing near Grand Lagoon subdivision is

                 located 1200 feet east of Grand Lagoon Boulevard. There are

                 two 24-inch culverts at this locatio n which drain

                 approximately 50 acres of mostly undeveloped land   north of

                 the highway. The runoff flows south through the culverts and

                 into a ditch which carries the water about 200 feet to a

                                              5-50

                 30-inch pipe. This pipe.then carries   the flow about 450 feet

                 to the south where it discharges into Big Lagoon.

                 Since t'here is litt le development north of Gulf Beach Highway

                 at this location, there are no serious stormwater problems

                 north of the road. However, it is suspected that water does

                 cross over the highway. There is also a problem with

                 structural flooding of a residence located on Chanticleer

                 Drive south of Gulf Beach Highway. The 30-inch storm pipe

                 runs under an auxiliary building on residential property

                 which has experienced frequent and severe flooding.

                 There are other stormwater problems located south of Gulf

                 Beach Highway. The Grand Lagoon area has experienced

                 significant street flooding. Water has crossed over Ponte

                 Verde Drive at two culvert crossings which are part of the

                 subdivision's internal lake system. The flow of water over

                 the road was severe enough to actually wash out the roadway

                 at the culvert crossing nearest to Grand Lagoon Boulevard..,

                 The problems south of Gulf Beach Highway are compounded by

                 the runoff coming from the north. Any measures taken to

                 relieve the flooding north of Gulf Beach Highway should be

                 designed to route the stormwater around the lake system in

                 order to reduce the stormwater problems located south of the

                 highway-

                                               5-51

                 Drainage Alternatives

                 Alternative I

                 Alternative "I" consists of the installation of a stormwater

                 collection system along the north side of Gulf Beach Highway

                 and discnarge to a Boat Basin which is connected by a dredged

                 canal to Big Lagoon.

                 This alternative includes stormwater piping sufficient to

                 carry the runoff generated by a 25-year design storm.

                 Approximately 3000 feet of pipe would be required along the

                 north side of the highway and approximately 800 feet of pipe

                 would be necessary to connect the system to the Boat Basin.

                 most of the improvements can be placed within the right of

                 way of Gulf Beach Highway and Grand Lagoon Boulevard. An

                 easement will be required from Grand Lagoon Boulevard to the

                 Boat Basin.

                                                                           A

                 The approximate construction cost for Alternative "I" is

                 estimated to be $395,000. This results in a cost of $3,950

                 per acre for the drainage area located north of Gulf Beach

                 Highway. When the area of the subdivision located south of

                 the highway (which will also benefit) is figured in the cost

                 per acre drops to $1,975. A large portion of the area is

                 developed and consists mostly of one-third acre single-family

                 lots. If the area was totally developed with single-family

                 homes, the cost per residence would be approximately $987.

                                             5-52

                 Direct stormwater discharge to surface  waters can have a

                 significant impact on water quality.   Many surface pollutants
                 such as silt, heavy metals and fertilizers are transported by

                 stormwater during the first one-half inch of rainfall.

                 However, in this case, the impact will be less severe since

                 the area's sandy soils will absorb the first one-ha lf inch of

                 rainfall from a normal storm. Runoff from the area only

                 occurs during storms after a relatively wet p eriod when

                 the water table is near  the ground surface. Therefore, the

                 pollution content of the runoff has already been reduced by

                 recent rains which carried the pollutants into the soil. For

                 these reasons the environmental impact of Alternate I is

                 estimated to be slight.

                 Alternative II

                 Alternative "II" consists of the same general routing as

                 Alternative "I" but, instead of sizing the piping to handle

                 the peak runoff, Alternative "II" will utilize perforated

                 pipe to control the watertable. By controlling the

                 watertable, a significant amount of storage volume is made

                 available within the soil above the watertable. This can

                 significantly reduce the peak rate of r unoff and as a result

                 the piping size can be reduced.

                 The basic difference between this alternative and Alternative

                 "I" is that the piping is perforated and wrapped with a

                                              5-53

                 filter fabric to-keep the soil from@entering the pipe. The

                 piping would also be placed deeper in the ground to obtain

                 the greatest amount of storage in the soil above the pipe.

                 AS in Alternative "I", stormwater inlets will be installed to

                 collect the runoff which will occur during severe storms and

                 provide access for inspection and maintenance of the piping

                 The Escambia County Soil Survey indicates that the existing

                 soil consists mostly of the Leon Series. This type of soil

                 is very permeable and its characteristics are suitable for

                 the use of underdrains. However, the design of an underdrain

                 system requires specific soils information and it is

                 difficult to estimate the piping size requi,red and the

                 performance of the system without adequate soil testing.

                 Hence, the construction cost of this alternative is difficult

                 to estimate. For the purpose of this report we have assumed

                 that each pipe size, estimated in Alternative "I", can be

                 reduced between six to twelve inches. This will result in a

                 total construction cost of approximately $320,000 which iv a

                 $75,000 savings over Alternative "I". The resulting cost

                 per acre is $1,600 and the cost per lot is $800.

                 Since the "first-flush" of runoff will be absorbed by the

                 dewatered soil, to some degree, the environmental impact of

                 this alternative will be less than Alternative "I".

                                            5-54

                 Alternative Selection

                 AS shown in the Alternative Evaluation Table Alternative "II"

                 received the highest rating. This is due to its lower cost,

                 slight environmental impact, the ability to control flooding

                 and provisions for future extension. Alternative "I" has a

                 rating below Alternative "Il" due to its higher cost,

                 environmental impact and its inability to be extended.

                                            5-55

                                       TRE* ASURE HILL                                                             GRAND LA(

                                                                                                    _j
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                                                          '14

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                              NEW DETENTION POND        '@-,-NEW'STORMWATER                                                  C7-      c
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                       BIG        LAGOON-'- STATE PARK                                                               Z
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                           @V,

                                                 TABLE 5-9
                                               COST ESTIMATE
                                                ALTERNATE I
                                        GRAND  LAGOON SUBDIVISION

                                                                   Unit
                   Item Description      Quantity       Unit       Price      Total

                   36" RCP               1,500          L.F.       $48.00     $72,000

                   4211 RCP              1,100          L.F.       $60.00     *66,000

                   48" RCP                  450         L.F.       $77.00     $34,650

                   54" RCP                  800         L.F.       $92.00     $731600

                   Drainage Structures       12         EA         $1,500     $18,000

                   Road Crossings              2        EA        $12,000     $24,000

                   Driveway
                   Replacement              480         S.Y.       $20.00     $ 9,600

                   Sod                   8,000          S.Y.       $ 2.50     $20,000

                   Easement              Lump           Sum                   $10,000

                                                        Subtotal              $327,850

                                                        20% Contingency       $65,570

                                                        TOTAL                 $393,420

                                                        SAY                   $395,000

                                                     5-57

                                               TABLE 5-10
                                              COST ESTIMATE
                                             ALTERNATIVE II
                                       GRAND LAGOON SUBDIVISION

                                                                  Unit
                   Item Description      Quantity      Unit       Price      Total

                   24" RCP               1,500         L.F.       $29.00     $43,500

                   36" RCP                             L.F.       $50.00     $77,500

                   48" RCP                 .800        L.F.       $79.00     $63,200

                   Drainage Structures       12        EA         $1,500     $18,000

                   Road Crossings             2        EA         $12,000    $24,000

                   Driveway
                   Replacement              480        S.Y.       $20.00     $ 9,600

                   Sod                   8,000         S.Y.       $ 2.50     $20,000

                   Easement              Lump          Sum                   $10,000

                                                       Subtotal              $265,800

                                                       20% Contingency       $53,160

                                                       TOTAL                 $318,960

                                                       SAY                   $320,000

                                                    5-58

                                           TABLE 5-11
                                    ALTERNATIVE EVALUATION
                                    GRAND LAGOON SUBDIVISION

                                               Alternative I   Alternative II

                 Economic                            3                4

                 Environmental Impact                2                3

                 Level of Service                    4                4

                 Human Issues                        4                5

                 TOTAL                               13               16

                                              5-59

                 5.3.2 SEAGLADES AREA

                 The terrain in parts of Seaglades subdivision consist of the

                 highest land in the stu dy area with elevations ranging up to

                 45 feet above sea level. The highest ground is located south

                 of Gulf Beach Highway in the central portion of the

                 subdivision. The area north of the highway slopes from an

                 elevation of approximately 28 feet in the northwest section

                 to the southeast where the elevation of Gulf Beach Highway is

                 about 15 feet. Except for some residences along the highway,

                 the northern area is undeveloped. It appears that a

                 subdivision was planned for this area since there is a

                 network of cleared rights of way. However, the area is not

                 well drained, there is standing water in many of the rights

                 of way and no development has taken place. The drainage area

                 totals over 100 acres and the runoff crosses Gulf Beach

                 Highway through a 48-inch culvert which discharges into a

                 private pond located about 300 feet south of Gulf Beach

                 Highway. The 48-inch culvert seems adequate to handle thd
                 stormwater runoff'from the area. The culvert is also low

                 enough to drain the undeveloped area. A collection system

                 could be extended fromthe 48-inch culvert to facilitate

                 adequate stormwater controls. Assuming that the unimproved

                 rights of way have not been dedicated to the County, it would

                 be the developer's, or property owner's responsibility to

                 construct an adequate stormwater collection and treatment

                 system.

                                              5-60

                 The runoff south,of Gulf Beach Highway is routed through

                 several private ponds and eventually discharges into Big

                 Lagoon. There is also additional runoff from a large area

                 east of Seaglades which flows over Gulf Beach Highway and

                 enters the lake system. Some flooding south of Gulf Beach

                 Highway has been occurring due to the great amount of

                 discharge to the lake system. The connecting drainageways

                 between the lakes are also inadequate to control the runoff.

                 One solution could be to construct an overflow swale from one

                 of the upstream ponds. This would require a swale

                 approximately 400 feet in length and it would discharge to

                 Big Lagoon. The environmental impact of a relief swale

                 should be slight since the runoff is from undeveloped areas

                 and erosion of downstream drainageways will be reduced. In

                 order to c*ontrol the runoff which presently crosses Gulf

                 Beach Highway, the existing 18-inch pipe and its discharge to

                 the lake system should be upgraded. A grassed swale

                 approximately 500 feet in length will be needed.           A

                 The total construction cost for the improvements is estimated

                 to be $35,000. This cost does not include easement

                 acquisition since it is assumed the property owners will

                 grant easements in exchange for the drainage benefits they

                 receive. Based on a total of 30 acres located south of Gulf

                 Beach Highway that would benefit from the improvements, the

                 cost pe-r acre is $1,166.

                                              5-61

                 There is also one depressed area on the south side of Gulf

                 Beach Highway west of Flamingo Street that does not drain

                 properly. The area holds water for long periods after

                 extended heavy rains., The owner of the residence who is most

                 affected, has found it necessary to pump standing water out

                 of his yard after heavy rain. A solution to the problem would

                 require approximately 700 feet of pipe in order to drain the

                 water to Big Lagoon. There is no structural flooding and it

                 would be possible to install a relatively small pipe. This

                 pipe would not be designed to carry the peak flow, but it

                 would drain the area and greatly reduce the duration of the

                 yard flooding. The estimated cost for this construction

                 including easements through the adjacent property is $35,000.

                                             5-62

                                                                              SEAGLADES

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                                                   TABLE 5-12
                                                 COST ESTIMATE
                                                SEAGLADES AREA

                    AREA 1
                                                                      Unit
                    Item Description       Quantity        Unit       Price        Total

                    101, PVC                   700         L.F.       $ 9.00       $ 6,300

                    Structures                   4         EA         $1,400       $ 5,600

                    Sod                        700         S.Y.       $ 2.50       $ 1,750

                    Easements                  Lump        Sum                     $15,000

                                                           Subtotal                $28,650

                                                           20% Contingency         $ 5,730

                                                           TOTAL                   $35,380

                                                           SAY                     $35,000
                    AREA 2                                            Unit
                    Item Description       Quantity        Unit       Price        Total

                    48" RCP                      48        L.F.       $78.0.0      $ 3,744

                    Headwalls                    2         EA         $1,500       $ 3,000

                    Swales (Grading)         4,500         C.Y.       $ 5.00       $22,500

                    Grassing                 5,000         S.Y.       .$ 0.-30     $ 1,500

                                                           Subtotal                $30,744

                                                           20% Contingency         $ 6,148

                                                           TOTAL                   $36,892

                                                           SAY                     $37,000

                                                        5-64

                 5.3.3 QUINAVISTA AREA

                 most of the development in the Quinavista area is located

                 along-Gulf Beach Highway with scattered development extending

                 as much as 1200 feet north of the Highway. There is also

                 several hundred acres of undeveloped land located between

                 Gulf Beach Highway and Garcon Swamp. This land is fairly

                 high with elevations averaging about 25 feet. The land

                 slopes gradually to the south toward Gulf Beach Highway and

                 there are several depressions which contain standing water

                 during wet periods. Runoff from the area is usually not a

                 problem since the sandy soils absorb much of the rainfall.

                 The stormwater problems occur (as in other areas along Gulf

                 Beach Highway) during heavy rains after an extended wet

                 period. At present there is not a well defined stormwater

                 collection system. Some land owners are taking measures to

                 divert the runoff around their property which causes problems

                 for adjacent properties. The stormwater facilities along

                 Gulf Beach Highway are also inadequate. The existing      A

                 culverts are undersized and water flows over the Highway

                 during severe rains.

                 There are two existing culvert crossings on Gulf Beach

                 Highway in the Quinavista area that should be upgraded. One

                 is located at Casa Maria Lane and the other is about 850 feet

                 to the west. Each culvert drains over 100 acres and a

                 stormwater collection system is needed to transport the

                 runoff through the developed areas. A simple grassed channel

                                             5-65

                 would be sufficient and should be constructed to run directly

                 north past the existing development and then turn in a

                 general east-west direction. The east-west channel would

                 serve to collect the runoff which sheet flows to the south.

                 Several drainage easements would be required through private

                 property for construction and maintenance purposes.

                 Once the runoff is collected and routed past Gulf Beach

                 Highway a concrete lined channel should be constructed to Big

                 Lagoon. The terrain south of Gulf Beach Highway drops

                 quickly and the resulting steep channel slope would create a

                 water velocity which could easily erode an unprotected

                 channel.

                 Since the recommended system will inter-cept runoff    from

                 wooded areas without creating new discharge points, the

                 system should have little impact on the environment. The

                 improvements may actually benefit the environment by

                 controlling the runoff across the developed areas thereby

                 reducing erosion of unpaved roads and rights of way in the

                 area.

                 The construction cost including easement acquisition is

                 estimated to be approximately $130,000. Since the

                 improvements will serve approximately 250 acres, the

                 resulting cost per acre is $520.

                                                5-66

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                                               TABLE 5-13,
                                              COST ESTIMATE
                                             QUINAVISTA AREA

                                                                  Unit
                  Item Description      Quantity       Unit       Price      Total

                  48" RCP                   148        L.F.       $80.00     $11,840

                  Headwalls                   4        EA         $1,500     $ 6,000

                  Concrete Ditch         1,500         S.Y.       $18.00     .$27,000

                  Swales (Grading)       6,000         C.Y.       $ 5.00     $30,000

                  Structures                  2        EA         $2,000     $ 4,000

                  Grassing              16,000         S.Y.       $  0.30    $ 4,800

                  Easements                 2.5        Acre      $10,000     $25,000

                                                       Subtotal              $108,640

                                                       20% Contingency       $21,728

                                                       TOTAL                 $130,368

                                                       SAY                   $130,000

                                                     5-68

                5.3.4 TREASURE  HILL

                The Treasure Hill area consists of over 100 acres of
                developed land.' most of the area is relatively flat and

                slopes south toward Gulf Beach Highway. There is no well

                defined drainage system w ithin the subdivision. Most of the

                roads are not paved and in some cases the roads have been

                built up with red clay to a point that thenatural overland

                stormwater flow is blocked. There are also some naturally

                depressed areas.

                one such area is located 200 feet to 300 feet north of Gulf

                Beach Highway. This ar  ea is fairly long and runs parallel to

                Gulf Beach Highway between Statler Avenue and PleateaU Road.

                Another low area is located at the southeast corner of

                Cambria Drive and Beckstrom Road.   The area along the north

                side of Gulf Beach Highway near Cambria Drive is also low.

                All of these areas contain standing water for long periods

                after heavy rains. Since there are no drainage culverts

                across Gulf Beach Highway, the runoff is forced over the

                roadway near Cambria Drive. At least one business and

                several residences are severely affected by flood waters.

                There are also many graded roads which become impassable due

                to standing water.

                A solution to the problem requires construction of some type

                of stormwater collection system. many of the low areas can

                be drained by placing culverts under the roads within the

                                             5-69

                 subdivision and grading swales between existing lots. An

                 underground piping system may also be necessary. Based on

                 the limitedinformation presently available, it appears the

                 piping system should begin on Arrowhead Road and run west

                 to Medina Road. Since the piping will run perpendicular to

                 the existi ng roads, many drainage easements across private

                 property will be needed. A total of 1,800 feet of pipe will

                 be required to reach Medina Road and stormwater inlets should

                 be placed on each of the four roads that will be crossed.

                 Grass swales will also be needed to collect the stormwater in

                 areas west of Medina Road and north on Cambria Street.

                 Since the collected runoff will contain pollutants from the

                 developed area, it must be treated in some manor prior to

                 discharge to Big Lagoon State Park. Adequate treatment is of

                 special concern due to sediment from the clay roads within

                 Treasure Hill and the impact on the sensitive wetland areas

                 located south of Gulf Beach Highway. It is recommended that a

                 stormwater detention facility be constructed north of Gulf-'-

                 Beach Highway between Cambria Drive and Medina Road.. This

                 location seems suitable since it is presently undeveloped and

                 is several feet lower in elevation than the surrounding

                 property. Once the runoff is treated it can be discharged by

                 pipe across Gulf Beach Highway and into Big Lagoon State

                 Park. According to County Orthographic Aerial contour maps,

                 there is a natural drainage way located 900 feet south of

                 Gulf Beach Highway.

                                               5-70

                The construction cost for the recommended stormwater system

                is estimated to be approximately $395,000. This results in  a

                cost per acre of approximately $3,300.

                                              5-71

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                                                TABLE 5-14
                                               COST ESTIMATE
                                               TREASURE HILL

                                                                   Unit
                   Item.Description      Quantity       Unit       Price      Total

                   24" RCP                     96       L.F.       $28.00     $ 2,688

                   3011 RCP                  148        L.F.       $38.00     $ 5,624

                   36" RCP                1,200         L.F.       $48.00     $57,600

                   42" RCP                   700        L.F.       $60.00     $42,000

                   48" RCP                   550        L.F.       $77.00     $42,350

                   54" RCP                   200        L.F.       $90.00     $18,000

                   Headwalls                   8        EA         $ 1,200    $ 9,600

                   Inlets                      12       EA         $1,500     $18,000

                   Concrete Flume              1        EA         $2,000     $ 2,000

                   Pond Underdrains       1,600         L.F.       $20.00     $32,000

                   Road Crossing            Lump        Sum                   $10,000

                   Grading                1,500         C.Y.       $ 5.00     $ 7,500

                   Pond Excavation        7,000         C.Y.       $ 5.00     $35,000

                   Grassing               6,000         S.Y.       $ 0.30     $ 1,800

                   Easements                   3        Acre       $15,000    $45,000

                                                        Subtotal              $329,162

                                                        20% Contingency       $65,832

                                                        TOTAL                 $394,994

                                                        SAY                   $395,000

                                                    5-73

                 5.4 PERDIDO BAY RESORT AREA

                 Perdido Bay Resort consists  of approximately 500 acres of

                 mostly developed property.  Approximately 270 single-family

                 lots and several higher density residential areas have been

                 developed around an 18-hole golf course. The golf course was

                 constructed with an internal lake system that serves as an

                 outfall for the stormwater from most of the surrounding

                 development. The terrain is fairly flat a  nd except for  the

                 lake system there is not an extensive drainage system.

                 The roadways, with curb and gutters, were constructed at very

                 slight grades, and curb inlets are used to route the runoff

                 into shallow storm pipes which connect individually to the

                 lake system or Perdido Bay. many of the inlets and culverts

                 are in need of maintenance. Proper maintenance, such as

                 cleaning inlets, pipes and outfall ditches, should be

                 performed immediately. The soils in the area consist mostly

                 of Rutledge Sand which has poor natural drainage

                 characteristics.

                 5.4.1 DOUG FORD DRIVE

                 Doug Ford Drive serves as the o nly entrance road to Perdido

                 Bay Resort. It is reported that during heavy rains the road

                 becomes impassable due to several feet of water over the

                 road. many complaints regarding inadequate drainage have

                 been received. The situation is not just a minor

                                               5-74

                 inconvenience when the need for adequate hurricane evacuation

                 is considered. It is very possible that rains and high   tides

                 associated with an approaching hurricane could cut off   the

                 only evacuation route for Perdido.Bay Resort.

                 Upon review of the situation it was discovered that

                 approximately 100 acres of undeveloped land located north of

                 Doug Ford Drive drains south to the roadway. In addition, a

                 large part of the Clubhouse parking lot drains onto Doug Ford

                 Drive. Since the drainage facilities on Doug Ford Drive

                 consist of only one inlet and a 24-inch pipe, it is

                 apparent that improved stormwater controls are needed.

                 Three locations for improvements are recommended. The first

                 location is at the intersection of Doug Ford Drive and

                 Sorrento Road. The existing 24-inch culvert under Doug Ford

                 Drive should be replaced with a culvert having sufficient

                 capacity to handle the runoff carried by the swale along the

                 west side of Sorrento Road.                                A

                 The second area needing improvement is at the existing curb

                 inlet on Doug Ford Drive. This facility should be upgraded

                 to not only handle the runoff from the roadway,  but also the

                 runoff coming from the 100 acres of land located to the
                 north. The improvements required could consist of a grassed

                 swale along the north side of Doug Ford Drive to collect the

                 runoff, an adequate culvert under the road and a grassed

                 swale running south to Bayou Garcon. Based on preliminary

                                             5-75

                 runoff calculations a 54-inch diameter culvert would be

                 necessary.   A suitable easement to Bayou Garcon would also be

                 required.

                 The third recommended location for improvement is near the

                 west end of Doug Ford Drive at the intersection with Shoshone

                 Drive. The stormwater reaching this location is generated by

                 the Clubhouse parking area and Shoshone Drive. Since this

                 runoff will carry contaminants from developed   areas, it will

                 be necessary to provide treatment of the stormwater in order

                 to meet State water quality standards. Treatment could be

                 obtained by construction of a stormwater detention pond

                 located south of Doug Ford Drive. A limited amount of

                 stormwater piping and inlets would also be necessary to

                 collect the runoff and route it to the pond. Discharge from

                 the pond could be accomplished through a grassed swale

                 running south to Bayou Garcon.

                 The construction cost for the upgrading of the culverts on'

                 Doug Ford Drive is estimated to be approximately $54,000.

                 This cost combined with an estimated $98,000 cost for

                 improvements at the west end of Doug Ford Drive totals

                 $152,000. It is roughly calculated that Doug Ford Drive

                 provides access to approximately 500 acres of developed land.

                 This results in a total cost per area of $304.00 for the

                 recommended improvements to Doug Ford Drive.

                                              5-76

                                                                                    NEW DISCHARGE PIPE
                                                                                                                       NEW UNDERDRAINS
                             PEIRDID.0

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                                                 TABLE 5-15;
                                                (7 0.9 T FS T I M 1\1.'F@
                                               UUUU FURD DRIVE

                                                                    Unit
                   Item Descripton        Quantity       Unit       Price       Total

                   42" RCP                      150      L.F.       $59.00      $ 8,850

                   5411 RCP                      48      L.F.       $92.00      $ 4,416

                   Road Replacement           Lump       Sum                    $ 6,000

                   Headwalls                      4      EA         $2,0  00    $ 81000

                   Grading                   3,000       C.Y.       $ 5.00      $15,000

                   Grassing                 9,  000      S.Y.       $ 0.30      $ 2,700

                                                         Subtotal               $44,966

                                                         20% Contingency        $ 8,993

                                                         TOTAL                  $53,959

                                                         SAY                    $54,000

                                                       5-78

                                           TABLE 5-16
                                          COST ESTIMATE
                                   WEST END OF DOUG FORD DRIVE

                                                            Unit
                 Item Description    Quantity     Unit      Price     Total

                 24" RCP                 600      L.F.      $28.00    $16,800

                 36" RCP                 300      L.F.      $48.50    $14,550

                 Inlets                    5      EA        $1,500    $ 7,500

                 Pond Excavation       6,000      C.Y.      $ 5.00    $30,000

                 Sod                   2,000      S.Y.      $ 2.60    $ 5,200

                 Outlet Structure       Lump      Sum                 $ 4,000

                 Grading                 600      C.Y.      $ 5.00    $ 3,000

                 Grassing              1,500      S.Y.      $ 0.30    $    450

                                                  Subtotal            $81,500

                                                  20% Contingency     $16,300

                                                  TOTAL               $97,800

                                                  SAY                 $98,000

                                                  5-79

                 5.4.2 ARAPAHO DRIVE

                 Arapaho Drive is a residential street located at the south

                 end of Choctaw Avenue in Perdido Bay Resort. Severe     street

                 flooding occurs along Arapaho Drive on a regular basis. It

                 appears that the worst flooding occurs on the northern

                 portion of the road about 400 feet east of Choctaw Avenue.

                 There is a stormwater inlet on each side of the street at

                 this location which drains by pipe into the golf course

                 lake system.

                 The water elevation of the lake system is determined by

                 several control structures throughout the golf course. it

                 would be possible to lower the lake elevation and increase

                 the drainage cap acity of the stormwater system. But, this

                 would be objectionable to many residents and it would not

                 solve the problem. The problem is due mostly to the low

                 elevation of Arapaho Drive and the long route of stormwater

                 flow to Bayou Garcon. The lowest point on Arapaho Drive is

                 approximately four feet above mean sea level. In order to

                 obtain sufficient slope on a drainage system, a more direct

                 route to a positive outfall is necessary. This could be

                 accomplished by installing a piping system from Arapaho

                 Drive directly to Perdido Bay which is located about 800 feet

                 to the west. This approach would relieve the flooding

                 problems, but the water quality of the Bay could be degraded

                 by a new direct stormwater discharge. Therefore, a method to

                 limit the discharge of pollutants to the Bay is needed.

                                               5-80

                 Water quality could possibly be preserved by constructing

                 the inlets to the new storm system six inches or more above

                 the existing inlets. By doing this the runoff pattern during

                 light and medium rains would be unchanged. The new system

                 would function only during heavy rains to control the level

                 of flooding. The discharge from the new system would be

                 relatively pollution free since. the "first-flush" of runoff

                 (which carries the majority of pollutants) would be dire cted

                 into the golf course lake system.

                 The construction cost for such a system is estimated to be

                 approximately $99,000. It is also estimated that 73 lots

                 would benefit. This includes all the lots on Arapaho Drive,

                 Maya Court and the lots on Choctaw Avenue up to Navaho Drive.

                 The resulting cost per lot is, therefore, $1,356.

                                               5-81

                                               TABLE 5-17
                                             COST ESTIMATE
                                             ARAPAHO DRIVE

                                                                 Unit
                  Item Description      Quantity       Unit      Price      Total

                  36" RCP                 1,100        L.F.      $50.00     $55,000

                  Drainage
                  Structures                  4        EA        $2,000     $ 8,000

                  Driveway Repair          1 20        S.Y.      $20.00     $ 2,400

                  Road Patching            Lump        Sum                  $ 2,000

                  Easements                Lump        Sum                  $15,000

                                                       Subtotal             $82,400

                                                       20% Contingency      $16,480

                                                       TOTAL                $98,880

                                                       SAY                  $99,000

                                                   5-8?

                 5.4.3 ZUNI CIRCLE

                 Zuni Circle is a 300-foot residential cul-de-sac street.

                 located within Perdido Bay Resort. The problem on Zuni

                 Circle is due more to groundwater than stormwater.' The

                 watertable is above the curb most of the year. This creates

                 a slight flow of water over the curb and water continuously

                 stands in the gutters. The high watertable is also causing

                 the road to deteriorate much faster than other roads in the

                 area. The most feasible way to solve the problem seems to be

                 by installing underdrains along both sides of the road with

                 an outfall directly to Perdido Bay located 200 feet to the

                 west., The estimated cost for this work is $15,000 and would

                 benefit the six lots located on the street. it will also be

                 a benefit to Escambia County due to decreased road

                 maintenance.

                                             5-83

                5.5 PENSACOLA BEACH

                In Section 3, five problem locations were identified for

                Pensacola Beach, reference Figure 3-2. These areas  were as

                follows:

                    1)   Ft. Pickens Road, severe and extended duration

                         flooding of the roadway near Baywatch and

                         Boardwalk Condominiums.

                    2)   Minor parking lot flooding, businesses west side of

                         causeway on Little Sabine.

                    3)   One residence on Via DeLuna between Avendida II and

                         Avendida 12 has experienced flooding in the past.

                    4)   Yard flooding on Maldonado Drive, one block south

                         of Via De Luna.

                    5)   Street flooding, frequent and severe on Ensenada

                         Uno, a cul-de-sac.

                Of the five problems listed, solutions were developed for

                two of the problem areas, Ft. Pickens Road and Ensenada Uno.

                The second problem listed above was to such a minor nature,

                that it should not be included in a study of this scope.

                The third problem listed above would appear to be confined

                                           5-84

                 to one residence, which is built in,'a depression with

                 respect to everything around it. Since only one residence

                 is involved, it did not seem appropriate to address.that

                 problem in this report. A solution for this problem would,

                 on the surface, involve a great deal of expenseand would

                 probably involve pumped discharge and a long and expensive

                 force main to some point where gravity discharge is

                 feasible.

                 Problem area four would appear again to mainly effect one

                 residence. Since the structure on this lot is on pilings,

                 there is no danger of structural flooding. The yard

                 flooding is again due to the lot being located in a

                 depressed area with respect to everything around it.

                 5.5.1 FT. PICKENS ROAD

                 The severe street flooding on Ft. Pickens Road presents a

                 traffic hazard during most heavy rainfalls. It seems that

                 no roadway drainage exists to take stormwater away from the

                 pavement. Sand has built up along the edge of pavement pre-

                 venting water from leaving the pavement. The road grade

                 goes through a sag curve in front of Baywatch and Boardwalk

                 Condominiums. It is this location where stormwater collects

                 and reaches a depth of two to three feet in the travel lane.

                                            5-85

                 Alternative one involves the construction of a drainage

                 swale along the north side of Ft. Pickens Road between the

                 pavementledge and the parking lot for Boardwalk

                 Condominiums.

                 This swale will take runoff from the roadway and provide

                 discharge through percolation of water stored to a depth of

                 0.5 feet. Water above this elevation will be discharged via

                 a paved concrete swale to a point approximately 450 feet

                 north of the center,line of Ft. Pickens Road, and 100 feet

                 south of Santa Rosa Sound. This paved swale would be

                 constructed through the landscaped area between the paved

                 parking lots of Baywatch and Boardwalk Condominiums.

                 The paved swale section proposed would be a V-section five

                 foot wide with a 5:1 side slope.

                 The cost tabulation for this alternative is shown on Table

                 5-18.
                                                                          A

                 The second alternative for this location involves construc-

                 tion and expansion of the grasses swale proposed in alternate

                 one. This alternative would provide a means of discharging

                 stormwater should it not be pssible to obtain gravity

                 discharge.- The swale area is expanded to provide storage of

                 the first one-half inch of runoff from the contributing

                 drainage area, estimated to be 50 acres.

                                           5-86

                 After this volume is filled, the pump s would cut on and

                 evacuate detention storage provided in the pond. Under this

                 option, the pumps would not always be able to evacuate

                 stored stormwater as fast as it is entering, therefore, some.

                 temporary minor flooding is possible, although not likely

                 except during extreme events.

                 The pumped stormwater will be discharged through a six (6)

                 inch diameter force main and discharged into the boat basin

                 in Lafitte Cove, four hundred and fifty (450) feet to the

                 northeast of the proposed detention/retention swale.

                 The tabulated cost estimate for alternate two is shown on

                 Table 5-19.

                 Compared to the first alternate, this alternate at

                 $44,000.00 is almost double the estimated cost of alternate

                 number one, which costs $23,000.00.

                 The pumped storage alternate two does provide an environme'n-

                 tal improvement over alternate one at a slightly reduced

                 level of service. Maintenance and operations cost for the

                 pumping station were not included in the cost estimate, but

                 is expected to be around five thousand ($5,000.00) dollars

                 annually.

                 The point evaluation for these two alternates is shown on

                                           5-87

                 Table 5-19. Based on the evaluation,    alternate one is the

                 preferred solution.

                 5.5.2 ENSENADA UNO

                 The problem here is again severe steet flooding of    extended

                 duration. Basically the street has no place to drain. All

                 yards along the east and of the cul-de-sac street have been

                 filled to well above road grade.

                 There does not appear to be a simple solution to this

                 problem. It is recommended that an oversize inlet be placed

                 at the low point on the cul-de-sac and a small submersible

                 pump with float controls be placed in the inlet. Discharge

                 will be pumped through a 3 or 4 inch force main along Via De

                 Luna to a large private lake approximately 1050 feet east of

                 the cul-de -sac. Additionally, 6-inch diameter perforated

                 pipe should be extended fifty to seventy five feet from the

                 inlet to maximize the infiltration of stormwater.

                 The only other option is the construction of a gravity storm

                 sewer. However, there does not appear to be anywhere to

                 drain by gravity without disturbing one or more residences

                 on the steet. Also, a gravity drain to the Sound may prove

                 difficult to construct without providing some sort of treat-

                 ment prior to discharge.

                                            5-88

                                                                TABLE 5-18

                                                             COST ESTIMATE
                                                             ALTERNATE ONE
                                                  PENSACOLA  BEACH    FT. PICKENS ROAD

                   Item Description                    Quantity           Units         Unit Price          Total

                   Swale Excavation                        900            C.Y.                5.00          4,500.00

                   Paved Swale                             250            S.Y.               35.00          8,750.00

                   Remove Existing Pavement                 60            S.Y.                3.30             200.00

                   Relocate Dumpster Pad                    16            S.Y.               50.00             800.00

                   Sodding                              15,000            S.F.                0.20          3,000.00

                                                                                             TOTAL         $17,000.00

                                                             20% ENGINEERING & ADMINISTRATION               3,500.00

                                                                            + 20% CONTINGENCIES             4,500.00

                                                                                     GRAND TOTAL           $25,000.00

                                                                TABLE 5-19

                                                              COST ESTIMATE
                                                              ALTERNATE TWO
                                                   PENSACOLA  BEACH    FT. PICKENS ROAD

                   Item Description                    Quantity           Units         Unit Price           Total

                   Swale Excavation                        1600            C.Y.                5.00          8,000.00

                   Pump Station and   Wet
                       Well 2-250 GPM Pumps                Lump Sum                                          15,000.00

                   6" P.V.C. Force Main                     450            L.F.               10.00          4,500.00
          Ln
          1@       Sodding                              15,000             S.F.                0.20          3,000.00
          CD
                   Pavement Removal
                       and Replacement                       30            S.Y.               10.00             300.00

                                                                                              TOTAL         $31,000.00

                                                              20% ENGINEERING & ADMINISTRATION               6,000.00

                                                                             + 20% CONTINGENCIES             7,000.00

                                                                                      GRAND TOTAL           $44,000.00

                                          TABLE 5-20'

                                     ALTERNATE EVALUATION
                              PENSACOLA BEACH   FT. PICKENS ROAD

                                                      ALTERNATE     ALTERNATE
                                                        NO. 1         NO. 2

                Economic Impact                           4             2

                Environmetal Evaluation                   2             4

                Level of Service Provided                 4             3

                Downstream Impacts                        2             3

                Human Issues Evaluation                  3.8           3.2

                                                        15.8          15.2

                                           5-91

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                 The pumped discharge option seems to be the best solution

                 for this location. The total cost of this solution is

                 estimated to be twenty-four thousand dollars ($2,400.00).

                 5.6 JONES SWAMP AND GARCON SWAMP BASINS

                 Only a small portion of Jones Swamp lies in the study area

                 and no significant problems were identified   in this study.

                 There are significant problems associated with the swamp

                 further east outside of the study area. No structural

                 measures are proposed in the basin.

                 The Garcon Swamp Basin is entirely located within the study

                 area, but to this point is substantially undeveloped. The

                 Perdido Bay Resort west of Bauer Field Road is in the Garcon

                 Bayou Basin and drainage problems.were identified in that

                 area and solutions are addressed in Section 5.4.

                 However, east of Bauer Field Road (C.R. 293) there were no

                 problems identified within the Garcon Swamp Basin.

                 Potential problems are addressed by the non-structural

                 measures recommended in Section 6.1.

                                             5-94

                 5.7 PARADISE  BEACH

                 Most of the residential development in Paradise    Beach is

                 along Perdido Bay and  Highway 98 (Lillian  Highway).   There is

                 no central drai nage system. Most of the   runoff flows

                 overland into the Bay or is  collected by  roadside swales

                 which discharge into the Bay. Due to the    relatively  high

                 land and short outfall distance to the Bay, no stormwater

                 problems are apparent'.

                 There is a large undeveloped area located south of Highway 98

                 which currently drains through a 48-inch culvert under the,

                 Highway. Future development of this area will require

                 adequate stormwater planning in order to meet County
                 regulations and not adversely'impact the nearby surface

                 waters.

                 5.8 BRONSON FIELD BASIN

                                                                              A

                 Bronson Field is an abandoned U.S. Navy Air Base. A major

                 portion of the surface runoff from the Base is collected by a

                 relatively large ditch along the south property line. This

                 ditch is connected to Perdido Bay and in recent years it has

                 been extended to the northeast to assist in the drainage of

                 Wildwood Lakes subdivision. Wildwood Lakes is located east of

                 Bauer Road and has an internal lake system which connects to

                 the Bronson Field ditch through two 36-inch culverts under

                 Bauer Road. All the streets within the subdivision are known

                                              5-95

                 to flood for a short period to a depth of 6 to 9  inches

                 during extremely heavy rains. However, it seems   that the

                 developers anticipated the situation and constructed all the

                 homes well above street level. Water has also crossed over

                 Bauer Road during some of the most severe rains. Due to the

                 minor and infrequent nature of the flooding, no improvements

                 are recommended.

                 5.9 PERDIDO KEY/INNERARITY AREA

                 5.9.1 PERDIDO KEY

                 Historically, there has been very little runoff from the

                 largely undeveloped lands on Perdido Key. The loose white

                 sand on the Key has excessive natural drainage due to the

                 rapid permeability of the soil. The voids within the soil

                 provide space for the storage of infiltrated rainfall. As

                 much as one-third of' the total soil volume above the water

                 table is void and available for stormwater storage. As a-i

                 result only areas with a high water table produced stormwater

                 runoff on the Key before extensive development began in the

                 late 19701s.

                 The majority of the recent development has been along Perdido

                 Key Drive. There is no defined stormwater system along the

                 roadway and as individual projects were developed, individual

                 stormwater systems were constructed. most, if not all the

                 systems utilize the high infiltration rate of the natural

                                              5-96

                 soil. In general, stormwater is directed from    impervious

                 areas to pervious areas where the runoff infiltrates   the soil

                 and percolates down to the water  table. This method   is

                 effective as long as the percolation areas do not become

                 "blinded' by fines, oils or other foreign material. It is

                 also necessary to have sufficient storage volume in the soil

                 above the watertable. Since there is no   discharge to

                 surface waters, this method resul ts in very little pollution

                 of surface waters.

                 Since the majority of properties on Perdido Key are

                 waterfront and well drained, a stormwater master plan is not

                 needed for these areas. However, there is a fairly large and

                 mostly undeveloped interior area in the Gulf Beach Heights

                 Subdivision. A portion of this area outfalls into Old River

                 through 3-48" RCP's under River Road. The area is

                 characterized by remnants of sand dunes with fairly high

                 ridges and long low areas between the ridges.    The lower

                 areas contain standing water most of the year. Except for the

                 area which outfalls into Old River, most of the low areas

                 drain to the east through culverts under Perdido Key Drive.

                 Most of the low areas contain wetland vegetation and will be

                 protected from filling to some degree by the United States

                 Army Corps of Engineers and the Florida Department of

                 Environmental Regulation wetland regulations. Since the low

                 areas act as natural drainage ways during heavy storms, it is

                 important that they are preserved and not filled during the

                 development of the area.

                                              5-97

                 5.9.2 INNERARITY PENINSULA

                 The Innerarity area is approximately five miles long and

                 about one-half-mile wide, at the widest point. it is

                 bordered on the north by Perdido Bay and on the south by the

                 intracoastal waterway. The soil, for the most part, is sandy

                 and well drained. The stormwater system consists mostly of

                 roadside swales with no central well defined collection

                 system. Due to the relatively short distance of overland

                 flow to the adjacent surface waters there seems to be no

                 serious problem with flooding caused by stormwater runoff.

                 However, there are some slightly depressed areas with a high

                 water table in which some ponding of stormwater was observed.

                 This ponding seems to be of short duration and no structural

                 flooding was discovered. It appears that periodic

                 maintenance of the existing roadside ditches could eliminate

                 some of the ponding problems.

                 The quality of the stormwater runoff in the Innerarity are-a

                 is of special concern. There are many unpaved clay streets

                 which run perpendicular to the shoreline. Runoff flows along

                 these streets carrying suspended clay particles and silt

                 directly into the nearby surface waters. Measures should be

                 taken to stabilize the roads and control the discharge of

                 pollutants.

                                              5-98

                 5.10 TARKILN BAY

                 The Tarkiln Bay area is almost entirely undeveloped. The

                 land around Tarkiln Bayou consists mostly of low wetland

                 areas. There is a large area of high ground located to the

                 west of Tarkiln Bayou on Perdido Bay. This area is highest

                 along the Bay and slopes gradually toward the Bayou. Due to

                 the pristine nature of Tarkiln Bayou and the surrounding

                 area, special care should be taken during its development.

                 5.11 SANDY CREEK/WEEKLEY BAYOU BASIN

                 The Sandy Creek Basin is mostly undeveloped east of Bauer

                 Road. The land is fairly flat with wetland areas separating

                 areas of higher elevation. It will be important during the

                 development of this area that the existing wetland areas and

                 associated drainageways are preserved. Some of this area is

                 classified as a flood zone according to the Federal Emergency

                 Management Agencies Flood Insurance Rate Map. The flood

                 elevations have not heen determined and it is recommended

                 that future developments establish a safe building elevation

                 based on detailed stormwater ca lculations.

                 The Weekley Bayou area is located west of Bauer Road and is

                 mostly developed with single-family residences. The land is

                 relatively high and slopes toward Weekley Bayou. -Some minor

                 stormwater problems occur in this area. It seems that most

                                             5-99

                 problems can be resolved with routine maintenance of the

                 existing roadside ditches

                                              5-100

                              6.0 NON-STRUCTURAL RECOMMENDATIONS

                6.1 GENERAL RECOMMENDATIONS

                During the course of this study, a number of factors, not

                attributable to natural causes, have been identified that

                are perceived by residents in the area as causing or contr--*-

                buting to drainage problems ex perienced. Some of these fac-

                tors are more apparent than oth ers, but most possess some

                degree of validity.

                Those factors that have been determined  to contribute the

                most to drainage problems in the area are as follows:

                    1)    Inadequate or no maintenance of the existing

                          drainage network of pipes and ditches.

                    2)    Construction of roadway embankments (fill

                          sections).

                    3)    New developments and the associated increase in

                          stormwater runoffs.

                    4)    Alterations of drainage by adj acent property owners

                          who fill or excavate on their property.

                    5)    Stormwater improvements to relieve problems in one

                          area that create new problems in another area.

                                            6-1

                     6)   Inadequately sized driveway culverts.

                     7)   Sediment deposition into streams, bayous, and yards

                          caused by unstabilized roadways or ditches.

                 All of the above concerns can be addressed by aggressive and

                 comprehensive maintenance and regulatory programs.

                 General maintenance recommendations that apply to the entire

                 study area are as follows:

                     1)   Clear and remove weeds, brush, beaver dams, and

                          trees from major drainage channels (D.A. > 30 Ac.)

                          at least twice annually.

                     2)   Inspect major channels a minimum of once a year for

                          sediment accumulation and remove by dredging if

                          necessary.

                     3)   Clean and mow roadside ditches at least three times
                          per year, including cross drains and driveway     A

                          culverts.

                     4)   Where easements do not exist for maintenance of

                          drainage facilities, pursue obtaining easements,

                          even if it means condemning property. Maintenance

                          is too critical to area drainage not to have ease-

                          ments for that purpose, particularly with the large

                          number of open ditches.

                                            6-2

                It is anticipated that an increase in road operations staff

                will be nece ssary to accomplish this level of maintenance

                and those costs have been included in the analysis of struc-

                tural alternatives in Section 5.0.

                Regarding new roadway construction in the   study area, an

                important factor must be considered in their design and

                construction. Since most of the area is vi   rtually level,

                stormwater will tend to build up in layers on   the land and

                flow in sheets toward an outlet. When the sheets reach a

                roadway in a fill section, the roadway ditch, or in most

                cases., the property adjacent to the roadway becomes a con-

                centration point for tremendous volumes of  water. Since the

                ditches are so flat, normal roadway ditch sections will not

                suffice. In fact, there are areas adjacent to Dog Track

                Road that flood to depths of two to three feet and cover

                fifty (50) to seventy-five (75) acres.

                Two options exist to deal with this problem. One option i's

                to construct an extensive longitudinal conveyance   system on

                the upstream side of the roadway. To do this would require

                additional right-of-way and unusally large ditch sections

                and large, low head driveway culverts or bridges. Even this

                will not work if cross-drain culverts do not have a positive

                outlet.

                                           6-3

                A second option  that may have a higher initial cost but

                would be much less expen sive over the long term would be to

                provide longitudinal collection channels along the rear pro-

                perty lines of  the property abutting the upstream side of

                the roadway and  provide lateral channels.to carry stormwater

                through ''cross-drain culverts perpendicular to the roadway.

                This solution would require more planning effort and higher

                property acqu isition costs, but would provide a safer, more

                efficient method of collecting and transporting stormwater

                from one side of the roadway to the other. The obvious

                advantage is the absence of large, deep ditches immediately

                adjacent to the roadway and subsequently the need for large

                expensive driveway culverts to enable access to the roadway.

                Another advantage to this solution is the ability to space

                large cross drains further apart, rather than have the bat-

                tery of culverts existing under the major roadways in the

                area. Most of these culverts do little but equalize water

                                                                            A
                levels from one side of the road to the  other, since no

                positive outlet exists particularly along Blue Angel Parkway

                and Sorrento Road.

                If it is expected that development along a roadway will be

                limited or prohibited, then these two options are not needed

                except in those areas where development exists prior to

                roadway construction.

                                            6- 4

                In these areas, it may be necessary to alter the drainage

                design concept to preven t adverse impacts to existing deve-

                lopments along the roadway.

                Even though new developments effect stormwater runoff in

                terms of water quality and quantity, existing ordinances, if

                properly enforced should deal effectively with new develop-

                ments to minimize any adverse impacts. Escambia County's

                Stormwater Management and Conservation Ordinance No. 86-32

                deals effectively with the rate and quality of stormwater

                leaving new developments.

                Review of this ordinance reveals that developers are

                required to control the rate of runoff from their project

                sites to predevelopment levels for up to the critical dura-

                tion 25 year design storm. This duration is determined by

                computing the peak site discharges associated with various

                duration events. The event that produces the largest volume

                or highest rate of net stormwater runoff (post-development'

                less pre-development) is the critical duration event.

                Also, developers are required to retain onsite a volume of

                water equivalent to the first inch of runoff to remove

                pollutants and suspended solids by preventing discharge of

                this stormwater into surface waters and requiring evacuation

                of this stored stormwater by percolation, evaporation, or

                evapotranspiration.

                                           6-5

                 it is this area of the  ordinance that needs expanding to

                 include other methods  of treating stormwater runoff. Due to

                 the high water tables  in most of the study area, recovery of

                 the retention volume within a reasonable period of time is

                 highly unlikely. For this reason, alternate treatment

                 methods should not only be allowed, but be encouraged, for

                 those areas with soil types not conducive.to infiltration.

                 The Florida Department of Environmental Regulation currently

                 allows detention with filtration, "wet" detention, and

                 wetland discharge as alternate methods of meeting    stormwater

                 discharge water quality requirements. It is recommended

                 that Escambia County should encourage the use of "wet"

                 detention facilities for stormwater treatment. These faci-

                 lities have demonstrated treatment efficiencies equivalent

                 to other methods and pollutant removals of phosphorus,

                 nitrogen, and some metals actually exceed that of other
                 treatment methods.(2)
                                                                             A

                 These facilities have a permanent pool or volume of water

                 with flat littoral shelfs above the permanent pool. Gravity

                 draw down of this littoral zone is allowed after a specified

                 period of detention.

                 These facilities have the advantage that they can become

                 attractive additions to a development due to their natural

                 appearance and functioning.

                 (2) "An Assessement of Stormwater Management Programs",
                     December, 1985, Camp, Dresser & McKee

                                              6-6

                current  DER criteria for these facilities are listed on

                Exhibit  6-1. Recommended  wetland species, that are required

                planting for the littoral  shelf around the perimeter of the

                permanent pools are listed on Exhibit 6-2.

                One drawback to utilizing this treatment method is the ina-

                bility to process these facilities under the general permit

                requirements of F.A.C. 17-25. Instead, these facilities

                must be constructed under the construction permit require-

                ments of F.A.C. 17-25, a more rigorous technical and admi-

                nistrative procedure. This could act as a deterrent to

                widescale use by developers.

                Another area where E scambia County must intensify enfor-

                cement procedures is in the area of single family construc-

                tion activities on individual lots. Grade changes made on

                one lot can seriously impact a neighboring lot. For this

                reason, some review procedure must be implemented which eva-

                luates the impact of individual lot construction. This is"

                particularly important since ditching or filling of the

                level terrain in the study area can modify the hydrology of

                an entire watershed.

                This same type of review should also include minor drainage

                improvements, ditch maintenance, roadway grading activities,

                and driveway pipe installations by Escambia County Road

                                           6-7

                Operations. An   engineering evaluation of the impact of any

                construction by  Road Operations personnel should be made to

                insure that the  improvements made do not impact other areas

                in the drainage  basin or significantly alter existing

                drainage patterns in the area where improvements are made.

                A fragmented approach to solving localized drainage problems

                should be avoided. This review process would apply only to

                new construction where grade changes are necessa ry, not nor-

                mal maintenance activities such as cleaning ditches and

                storm sewers. This maintenance should not include grade

                change changes in ditches that change the direction of flow

                or introduce new stormwater into a system. Roadway fills

                for graded unpaved roads should utilize materials native to

                the area where the construction is taking place. The intro-

                duction of material containing a substantial percentages of

                fines, such as clays and silts, to an area predominantly

                sand should be avoided, unless it is determined by the

                County Engineer that native materials do not provide the

                structural stability required for the roadbed.

                This is important, since the  introduction of fines may clog

                or blind native soils and reduce their ability to infiltrate

                stormwater.. Also, significant grade changes in road grading

                operations should be avoided, unless an engineering eva-

                                           6-8

                 luation of the anticipated grade change is made. No change

                 in the existing drainage system should ever be a part of

                 road maintenance activities. If it is anticipated that

                 changes to the road drainage system are required, then an

                 engineered plan should be prepared for that purpose.

                 In no instance, should driveway culverts be installed

                 without an engineering evaluation of the culvert size(s)

                 required to safely pass expected flows in the ditches. This

                 evaluation is necessary to insure that improperly sized

                 culverts do not impede the flow of stormwater and either

                 cause or increase flooding of private. property.

                 6.2 SPECIFIC RECOMMENDATIONS FOR SELECTED AREAS

                 The recommendations made in Section 6.1 apply to all basins

                 within the study area. However, speci-fic recommendations for

                 particular areas are needed due to problems inherent to an

                 area.

                 For those areas, new guidelines or particular emphasis of

                 some of the general recommendations is required.

                 For instance, in Section 5.1, in the analysis of alter-

                 natives for the Bridge Creek Basin, areas are shown on

                 Figure 5-1 where maintenance of natural storage is

                 required. It is recommended that these areas be purchased

                                            6-9

                 the wetland area. The Florida Department of Environmental,

                 Regulation has strict guidelines outlining the use of

                 wetlands to treat both point and non-point source discharge

                 into wetlands.

                 No roadway should be proposed across the swamp which would

                 impede the flow through the swamp or alter natural flow

                 velocities. Since the slow methodical movement of water

                 through the swamp is a key feature to the pollutant removal

                 efficiency of the swamp, channelization of stormwater in the

                 swamp or signi ficantly restricting the flow area should not

                 be allowed.

                 Much of the coastal area south of the Garcon Swamp Basin and

                 north of Gulf Beach Highway remains undeveloped. New deve-

                 lopments in this area should consider two factors. First,

                 the existing infrastructure along Old Gulf Beach Highway is

                 inadequate to handle existing flows. Therefore, any new
                 developments north of Old Gulf Beach Highway should consid'6r

                 the capacity of the system along and unde r the highway in

                 designing the detention facilities required by ordinance to

                 serve their developments. For this reason, the discharge

                 from the development should in many cases be less than pre-

                 development-due to restrictions downstream.

                 Developments in this area should also consider that there

                                           6-10

                 are numerous depressions in  this area which  fill during

                 storms and flood large areas to depths of two (2) to four

                 (4) feet. Flood elevations can be controlled with proper

                 design of a drainage system which controls the rate of

                 discharge, but allows evacuation of stormwater early enough

                 in a storm so that massive accumulation of stormwater is

                 prohibited.

                 Another area where potential problems exist is Pensacola

                 Beach. It is recommended that future developments on the

                 Beach be required to meet Escambia County's Stormwater and

                 Conservation Ordinance No. 86-32 in designing stormwater

                 management facilities to serve developments. Due    to the

                 tremendous capability of natural soils on the beach to per-

                 colate stormwater, there has been too much reliance on the

                 soils to handle large amounts or stormwater without gravity

                 outfalls. Future developments should consider providing

                 drainage systems which meet all regulatory requirements, but

                 have the capability of gravity discharge of overflow storm-

                 waters. All of the problems occurring on Pensacola Beach

                 are due to the absence of a drainage system that provides

                 discharge of stormwater when the native soils are saturated

                 and cannot intake surface runoff as fast as it is being

                 received..

                 If existing stormwater ordinances are enforced and surface

                                            6-11

                discharge capabilities are provided, future problems can be

                avoided.

                The recommendations made in this section and Section 6.1, if

                followed, will greatly aid in the management of existing

                problems and the prevention of future stormwater quantity or

                quality problems.

                                           6-12

                       CURRENT DER CRITERIA FOR WET DETENTION SYSTEMS

                a)  1" of runoff storage above level of permanent pool.

                b)  This volume to be bled down at a slow rate. No more

                    than 1/2 volume to be discharged in first 60 hours

                    following an event.

                c)  Volume in the permanent pool must provide for a resi-

                    dence time of at least 14 days. This volume may be

                    determined by estimating 3.83% of annual average runoff.

                    A more empirical approach sometimes used is calculated

                    by taking 2 inches times the impervious acreage in the

                    project plus 1/2 inch times the pervious acres.

                d)  A littoral shelf should be provided by extending and

                    gently sloping the sides of the facility (6:1 or flatter)

                    out to a point 2-2.5 ft. below the water's surface.

                e)  No more than 70% open water is recommended. The       A

                    remaining 30% (i.e., littoral shelf) typically is

                    established with aquatic vegetation. A layer of muck

                    (6" recommended) may be incorporated into the littoral

                    area to promote establishment of wetland vegetation.

                    Planting of native aquatic plant species is highly

                    recommended. Lining the bottom and sides of these faci-

                                                                 EXHIBIT 6-1

                     lities with a la yer of organic material such as much

                     appears to be an attractive alternative when potential

                     groundwater contamination problems are apparent..

                 f) A mean depth of 3-10 ft. should be planned for the per-

                     manent pool.

                 g)  Inlet structures should be designed to minimize tur-

                     bulence in the pond. Baffles are the most commonly used

                     structures for such purposes. Inlets should not be

                     located in close proximity to the outlet so as to pre-

                     vent short circuiting.

                 h)  Facilities that are potential sources for oil and grease

                     contamination must include a skimmer or other mechanism

                     to prevent these substances from leaving the facility.

                 i)  Erosion and sediment control BMP's must be used to

                     retain sediment on site during construction. BMP's must

                     be shown on the design plans and the engineer must pro@_
                     vide instructions'for proper 0 & M.

                 j)  Preferably, pretreatment in the form of landscape reten-

                     tion areas or perimeter swales is incorporated into the

                     stormwater management system to provide infiltration and

                     treatment of the first half inch of runoff to prevent

                     the wet detention lake from eutrophying. A credit

                                                                   EXHIBIT 6-1

                     against the required wet detention storage volume may be

                     provided depending upon the amount of stormwater

                     infiltrated. A dual pond system (see attached) is pre-

                     ferred and easily designed and constructed.

                 DER is currently in the process of developing a list of

                 suitable plant material and sources of supply for

                 appropriate native aquatic vegetation. Contact Keith

                 McCarron (904) 487-1779, Suncom 277-1779 for information.

                                                                  EXHIBIT 6-1

                          PLANT.SPECIES SUITABLE AND    SOMETIMES AVAILABLE
                                 FROM NURSERIES FOR   LITTORAL ZONE
                                  PLANTINGS OF DETENTION PONDS*

                  COMMON NAME                     SCIENTIFIC NAME

                  American elml                   Ulmus americana
                  Arrowhead                       Saggiteria, lancifolia
                  Banana water  lilY2             Nymphaea mexicana
                  Black guml                      Nyssa biflora
                  Bulrush                         Scirpus spp.
                  Button-weed                     Diodia virginiana
                  Buttonwoodl                     Cephalanthus.occidentalis
                  Carolina willowl                Salix caroliniana,
                  Coinwort                        Hydrocotyle umbellata
                  Cypressl                        Taxodium spp.
                  Cinnamon  fern                  Osmunda cinnamomea
                  Day flower                      Commelina. diffusa
                  Floating hearts2                Nymphoides aquatica
                  Frog's-bit                      Limnobium spongia
                  Hat pins                        Eriocaulon decangulare
                  Iris                            Iris hexagona.
                  Knotweed  (Smartweed)           Polygonum spp.
                  Lizard tail                     Sarurus cernuus
                  Loblolly bayl                   Gordonia lasianthus
                  Maidencane                      Panicum hemitomon
                  Pickerelweed                    Pontederia cordata
                  Popashl                         Fraxinus caroliniana
                  Redbayl                         Persia palustris
                  Red maplel                      Acer rubrum
                  Rushes                          Eleochris spp.
                  Sawgrass                        Cladium jamaicense
                  Sedges                          Cyperus spp.
                  Southern cutgrass               Leersia hexandra
                  Soft rush                       Juncus effusus
                  St. John's wort                 Hypericum fasciculatum
                  Swamp bayl                      Magnolia virginiana.
                  Swamp lilY2                     Crinum americanum
                  Virginia willowl                Itea virginica
                  Wax myrtlel                     Myrica cerifera
                  White water lily                Numphaea odorata
                  Yellow eyed  grass              Xyris spp.
                  Yellow pond  lilY2              Nuphar luteum

                      other species   may be suitable and may be used with
                      approval
                  1 = Tree or shrub; more suitable for higher elevations
                  2 = more suitable   for deeper water (i.e. greater than 1-2.
                      feet)

                                                                        EXHIBIT 6-2

                                                    US Department of Commerce
                                                    EOAA Coastal Services Center Library
                                                    2234 South Robson Avenue
                                                    Charleston, SC 29405-2413

                                                                           001 3575