COLLIER COUNTY FLOODPLAIN MANAGEMENT PLAN

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COLLIER COUNTY FLOODPLAIN MANAGEMENT PLAN Powered By Docstoc
					         Collier County Hazard Mitigation Plan                                 April 15, 2005



                                       7.0 FLOODPLAIN MANAGEMENT PLAN

                                                 TABLE OF CONTENTS

7.1 INTRODUCTION                                                        7-2
  7.1.1 Background                                                      7-2
  7.1.2 Purpose                                                         7-2
  7.1.3 Methodology                                                     7-2
  7.1.4 The Next Steps                                                  7-2
  7.1.5 Community Rating System                                         7-3
7.2 ASSESS THE FLOOD HAZARDS                                            7-4
  7.2.1 DRAINAGE BASIN INFORMATION                                      7-4
    A.  Main Golden Gate System                                         7-4
    B.  District No. 6 System                                           7-14
    C. Cocohatchee River System                                         7-22
    D. Gordon River Extension                                           7-30
    E.  Henderson Creek Basin                                           7-32
    F.  Faka-Union System                                               7-34
    G. Southern Coastal Basin                                           7-39
    H. Barron River System                                              7-43
    I.  Miscellaneous Interior Wetland Systems                          7-47
    J.  Miscellaneous Coastal Systems                                   7-53
    K.  Other Minor Areas Outletting Directly Into Adjacent Counties    7-58
    L.  City Of Naples Drainage Basin Information                       7-59
    M. City of Marco Island Drainage Basin Information                  7-68
    N. References                                                       7-69
    O. Collier County Drainage Basin Map                                7-73
 7.2.2     COLLIER COUNTY’S FLOODPLAINS                                 7-74
 7.2.3     TROPICAL CYCLONES                                            7-76
 7.2.4     SEVERE STORMS                                                7-76
 7.2.5     FLOODING                                                     7-76
 7.2.6     TSUNAMIS                                                     7-77
 7.2.7     REPITITIVE LOSSES                                            7-77
7.3   EVALUATE THE PROBLEM                                              7-78
7.4   SET GOALS                                                         7-82
7.5   REVIEW MITIGATION STRATEGIES                                      7-82

7.6   MITIGATION STRATEGIES                                             7-83
7.7   ADOPT THE PLAN                                                    7-83
7.8   IMPLEMENTATION, EVALUATION, REVIEW                                7-84




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7.1      INTRODUCTION

7.1.1    BACKGROUND

As identified in the Executive Summary of the Hazard Mitigation Plan, Collier County is
threatened by a number of different types of natural hazards. Of those identified in the Hazard
Mitigation Plan, Flooding was identified as having a “Highly Likely” probability of Frequency
(See Risk Summary, 2-7). These hazards endanger the health, and safety of the population of
the county, jeopardize its economic vitality, and imperil the quality of its environment. Because
of the importance of avoiding or minimizing the vulnerabilities to flooding hazards, the public and
private sector interests of Collier County have joined together to create a working group to
undertake a comprehensive planning process that has culminated in the publication of the “The
Collier County Hazard Mitigation Plan”, of which the Flood Mitigation Plan is a part there in.

A working group, entitled the Collier County Local Mitigation Strategy Working Group, with the
assistance of a Community Rating System (CRS) Subcommittee, has conducted detail studies
to identify the flood hazards threatening the jurisdictions of Collier County, and to estimate the
relative risks posed to the community by those flood hazards.

7.1.2    PURPOSE

As identified in Section 1.1 of the Hazard Mitigation Plan, the purpose of the Plan is to develop a
unified approach among county and municipal governments, along with inputs and participation
from the private sector, for dealing with identified hazard and hazard management problems in
the Collier County area.

7.1.3    METHODOLOGY

The development, operation, and composition to the Local Mitigation Strategy Working Group is
future described in Section 1.2 Program Organization in the Hazard Mitigation Plan. Section 1.3
Hazard Mitigation Plan Outreach, Participation & Meeting Requirements of the Hazard
Mitigation Plan describes the process for engaging the public with the development of this plan.
“Annex H “ of the Hazard Mitigation Plan provides meeting summaries.

7.1.4    THE NEXT STEPS

This “Floodplain Management Plan” is a draft that has been prepared under the guidance of the
CRS Subcommittee. Adoption and implementation should proceed according to the following
Steps:

      1. Following the public meeting on November 19, 2004, the Collier County Local Mitigation
         Strategy Working Group will review the comments submitted and revise this Plan as
         appropriate.
      2. The revised draft will be available for several weeks for public review. Copies will be
         sent to the agencies listed in the Section 1.3 of the Hazard Mitigation Plan.
      3. The Collier County Local Mitigation Strategy Working Group will review any comments
         received and make revisions as needed.
      4. The Hazard Mitigation Plan will then be submitted to the Collier County Commission for
         adoption.




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   5. The County Commission should include the funds needed to implement the
      recommendations in the future budgets as identified in Annex G of the Hazard Mitigation
      Plan.
   6. The people responsible for implementing the action items in “Annex I” should proceed
      with their assignments.

7.1.5   COMMUNITY RATING SYSTEM

Collier County currently participates in the Community Rating System, and qualifies for a Class
7 Rating. As part of the qualification for a Class 7 Rating, the community is required to prepare
and maintain a Floodplain Management Plan. This Floodplain Management Plan, as part of the
Collier County Hazard Mitigation Plan will serve as that plan. It is the goal of the CRS
Subcommittee to continue to work to make improvements to this plan so as to better serve the
citizens of Collier County, and to strive to improve the Class Rating for the County and the three
municipalities so that a greater percentage reduction of the flood insurance premium rates could
be available for the citizens in Collier County, Florida.

The City of Naples continues to minimize flooding in the community while reducing the cost of
flood insurance. The City joined the National Flood Insurance Program (NFIP) in 1971 and in
1973 the City adopted the general Federal Emergency Management Agency (FEMA) and NFIP
requirements into the building code ordinance. In 1992 Naples City Council adopted the
Community Rating System (CRS). The Community Rating System, sponsored by the NFIP,
recognizes and encourages community floodplain management activities that exceed the
minimum standards. Under the CRS, flood insurance premium rates are adjusted to reflect the
reduced flood risk resulting from community activities that (1) reduce flood losses, (2) facilitate
accurate insurance ratings, and (3) promote the awareness of flood insurance. Through the
City’s participation in the NFIP and a Class #6 rating with the CRS, owners of properties in the
City’s Special Flood Hazard Area (SFHA) are entitled to a 20% discount on their flood
insurance. In addition, homeowners in non SFHA’s receive a 5% discount on flood insurance.

Marco Island became a city on August 28, 1997 and at that time; all city codes and ordinances
became effective. Within the codes and ordinances, The City of Marco Island adopted the
National Flood Insurance Program (NFIP), the general Federal Emergency Management
Agency (FEMA) requirements, and the Community Rating System (CRS).
The Community Rating System, sponsored by the NFIP, recognizes and encourages
community floodplain management activities that exceed the minimum standards. Under the
CRS, flood insurance premium rates are adjusted to reflect the reduced flood risk resulting from
community activities that (1) reduce flood losses, (2) facilitate accurate insurance ratings, and
(3) promote the awareness of flood insurance. Through the City’s participation in the NFIP and a
Class #7 rating with the CRS, owners of properties in the City’s Special Flood Hazard Area
(SFHA) are entitled to a 15% discount on their flood insurance.
The adoption and participation in the Collier County Hazard Mitigation Plan will enable the City
of Marco Island to advance in the CRS. The new rating, Class #6, entitles the property owners,
in the City’s Special Flood Hazard Area (SFHA), to a 20% discount on their flood insurance.
In July of 2005, as required by the State of Florida, The City of Marco Island will adopt the new
Florida Building Code with all appendices, pertinent changes, references, and additions as
allowed by the Code. The adoption of the new Building Code will further advance the City of
Marco Island within the CRS. When the City achieves a Class #5 rating the property owners, in
the City’s Special Flood Hazard Area (SFHA), will receive to a 25% discount on their flood
insurance.



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7.2     ASSESS THE FLOOD HAZARDS

7.2.1    DRAINAGE BASIN INFORMATION

The information contained in this section was compiled from numerous engineering and
planning reports and the Collier County Stormwater Management Master Plan (Master Plan)
that was prepared as an initial product of the 1988 Growth Management Plan.

Collier County is a large land area of approximately 2000 square miles in southwest Florida.
The topography is extremely flat ranging from a high elevation of approximately forty (40) feet
above sea level in the unincorporated community of Immokalee in the northeastern portion of
the County to the coastline along the western and southern portions of the County. The typical
ground slope is approximately one (1) foot per mile in the western half of the County and less
than that in the eastern half of the County. The flat topography results in large areas of
sheetflow across natural ground, but road construction, agricultural operations, and urban
development have greatly altered this sheetflow in the western portion of the County.

Collier County is basically its own drainage watershed. The shallow topography, with the
Immokalee high located in the northeastern portion of the County near the Lee County and
Hendry County boundaries, creates a series of drainage basins with very little exchange of
stormwater crossing county lines. Additionally, in some locations agricultural and development
activities have constructed berms along their property lines that correspond to the County lines
that further define the drainage basin boundaries. The eastern half of the County is
predominantly federally owned wetlands that receive sheetflow as a part of the Everglades
system, but this remains in the eastern half of the County and continues the flow in a
southeasterly direction. The following information describes the various drainage basins in
Collier County and provides some information on the amount of effort that has been undertaken
to identify past flooding and other stormwater related concerns.

A.      MAIN GOLDEN GATE SYSTEM

The Main Golden Gate System is a large watershed area located in the west central portion of
Collier County. The basin was created by the construction of numerous canals by the Gulf
America Corporation (G.A.C.) in the 1960's for the purpose of draining the land for residential
purposes. The total area of the Main Golden Gate System is approximately 110 square miles
and can be divided into nine identifiable basins. They are as follows:

        A1.    Main Golden Gate Canal Basin
        A2.    Cypress Canal Basin
        A3.    Harvey Canal Basin
        A4.    I-75 Canal Basin
        A5.    Green Canal Basin
        A6.    Airport Road Canal South Basin
        A7.    Corkscrew Canal Basin
        A8.    Orange Tree Canal Basin
        A9.    951 Canal Central Basin

The area encompassed by the Main Golden Gate System contains a variety of land uses
including agriculture, residential estates, urban residential, and commercial. Of notable interest
within this drainage system is the four square mile residential development of Golden Gate City.


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This residential area was initially developed in the mid 1960's and contains the highest
concentration of dwellings within the system. There are also several large planned unit
developments (PUD's) in varying stages of completion within this system’s drainage area.
These PUD's are designed to incorporate a stormwater management plan, based on the latest
design storm standards as required by the local regulatory agencies, as a part of their
construction standards.

       Previous Studies
An examination of the Collier County Stormwater Management Department files revealed that
many studies have been prepared for the G.A.C. canal system. However, because of the
locations and control elevations of the various weirs, the system is divided into two major
drainage basins, the Golden Gate Basin and the Faka Union Canal System Basin. The needs
and proposed management plans for these two basins are addressed in the studies and their
differences are often described in detail.

"The Big Cypress Watershed, A Report to the Secretary of the Interior" by the
Everglades-Jetport Advisory Board in April 1971, is a very generalized report that mainly
describes the overall nature of the southwest Florida wetland area known as the Big Cypress.
This report mentions the encroachment of drainage canals and residences into the wetland
areas east of Naples and describes some of the effects of the resultant pollution sources but
does not enter into any significant discussion of the drainage system design or efficiency.

A report entitled "Hydrologic Study of the G.A.C. Canal Network, Collier County, Florida" was
prepared by the firm of Black, Crow and Eidsness, Inc. in October, 1974. This report presented
an evaluation of the general surface and groundwater hydrology of the Golden Gate Estates
area, including a detailed analysis of the flood characteristics for the canal network. It also
presented a discussion of certain environmental factors such as weed growth within the canals,
over-drainage of shallow groundwaters, and point discharge of surface waters into the estuarine
zone. Some of the recommendations, such as a redesign and reconstruction of some of the
water level control structures and an improved canal maintenance program, have been
incorporated into the canal system.

"Phase 1, Golden Gate Estates Redevelopment Study, Collier County, Florida" was prepared by
the Golden Gate Estates Study Committee in June, 1976. This report compiled a detailed
history of the development of drainage facilities within the Golden Gate Estates and
recommended that the canal system be modified to raise the water levels, reduce the rate of
fresh water runoff, limit the areas available for residential development, and restore as much of
the natural hydroperiod as possible to make the land more productive and less susceptible to
brush fires.

The "Proposed Boundary for the Big Cypress Basin, South Florida Water Management District"
report was prepared by Black, Crow and Eidsness, Inc. in September, 1976. The purpose of
this report was to review the available published literature concerning the Big Swamp of
Southwest Florida. The objective of the literature review was to obtain pertinent information
related to the hydrology, ecology, and physiographic nature of the Big Cypress, such that
detailed boundaries of the Big Cypress Basin could be delineated. The major value of this
report to assist in the design and implementation of a water management program for the
sub-basin is in providing an overall understanding of the total surface and ground water systems
within the Big Cypress area.




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The "Golden Gate Water Management Study" report prepared by Johnson Engineering, Inc. in
December, 1981, evaluated the feasibility of:

      1.       diverting a portion of the normal outflow from the Main Golden Gate Canal into
               other areas for water conservation purposes and/or

      2.       retaining increased amounts of surface water in the Main Golden Gate Canal
               system.

Several additional objectives were emphasized. One was to improve the response of the canal
system to summer flooding situations without subsequent depletion of ground water levels in the
winter (basically additional retentive capacity in the canals). An environmental objective was to
recreate a system that would more naturally respond to rainfall and therefore reduce the large
surges of outflow into Naples Bay. This report recommended that an increased canal
maintenance program be developed, four primary weirs on the Main Golden Gate Canal be
modified, and that the County begin the public acquisition of selected detention sites. Since this
report was written, a canal maintenance program has been upgraded and the four primary weirs
within the study area plus Weir No. 1 have been modified.

The "Regional Water Resources Study, Big Cypress Basin Program No. 2201" was completed
by the firm of Gee and Jensen Engineers-Architects-Planners, Inc. in November 1980. This
report was primarily concerned with the groundwater resources of western Collier County, but in
the discussion of groundwater, the effects of the drainage of surface water was detailed. The
recommendations of this report were to raise the control elevations of some of the drainage
systems to increase groundwater storage, reduce runoff losses, and increase freshwater head
in the surficial aquifer for maintenance of the fresh/salt water interface offshore. This report also
presented a good explanation of the effects that the Main Golden Gate Canal system has had
on the surrounding land.

A1. MAIN GOLDEN GATE CANAL BASIN

      Description
The Main Golden Gate Canal Basin is a large drainage area located in the southern and eastern
portions of the Main Golden Gate System and functions as the collector and discharge point for
the Main Golden Gate System. The basin contains approximately 49 square miles of residential
and agricultural land. The principal residential density is that found throughout the area known
as the Golden Gate Estates with typical lot sizes of 1.25 to 5 acres. The land use map identifies
most of this area as vested but some urban designated land, especially Golden Gate City, are
included.

The Main Golden Gate Canal Basin is bounded by the Cocohatchee River Basin to the north,
the Airport Road Canal (S.) and I-75 Canal Basins to the northwest, the Gordon River Extension
Basin to the extreme west, the District No. 6 System area to the south, the Henderson Creek
Basin to the southeast, and the Faka Union System area to the east.

       Historical Background
Prior to the construction of the G.A.C. canal network, the land was a mixture of wetlands and
uplands with almost no residential dwellings. The principal land uses were limited agricultural
sites and vast acreages of undeveloped wilderness. As the canals were constructed, a roadway
system was also constructed by the G.A.C. to provide access to the land for development



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purposes. The community of Golden Gate City was the only area developed at a planned urban
density.

      Description of Existing Facilities
The existing facilities within this basin consist of approximately 30 miles of primary canal and 8
miles of secondary canal. There are 7 water level control structures on the primary canal
system but none on the secondary canal system. The water level control structures are known
as weirs and will be identified by this title for the remainder of this report.

Weir No. GG-1 (identified in the Collier County Drainage Atlas Inventory as MGG-00-S0100)
was initially constructed in August, 1963 and is located near the junction of the Main Golden
Gate Canal and the Gordon River. This weir was totally reconstructed in 2003. It functions as a
salinity control structure and keeps the water level high enough to prevent the over-drainage of
the surrounding lands. The Airport Road Canal (S.) Basin empties into the Main Golden Gate
Canal a short distance upstream from Weir No. GG-1.

Weir No. GG-2 (MGG-00-S0120) was initially constructed in October, 1964, and is located
approximately 2 miles upstream from Weir No. GG-1 near the I-75 overpass. It was modified by
the Big Cypress Basin in 1985. The I-75 Canal Basin empties into the Main Golden Gate Canal
a short distance upstream from Weir No. GG-2.

Weir No. GG-3 (MGG-00-S0170) was initially constructed in January, 1969, and is located
approximately 6 miles upstream from Weir No. GG-2 at the eastern end of 17th Ave. S.W. It
was modified by the Big Cypress Basin in 1986 and 1993.

Upstream from Weir No. GG-3, the Main Golden Gate Canal begins to branch out into a
network of primary and secondary canals that also include other basins of the Main Golden
Gate System.. There are 4 additional weirs in the Main Golden Gate Canal with the uppermost
weir (GG-6) being located approximately 2 miles from the upper end of the canal. Weir No. GG-
4 (MGG-00-S0210) was modified by the Big Cypress Basin in 1987 and 1993. Weir No. GG-5
(MGG-00-S0240) was modified by the Big Cypress Basin in 1988. The flow of water within this
basin is to the southwest and the locations of the described weirs provide a controlled
step-down of the water level to prevent the over-drainage of the interior lands.

      Existing Condition/Capacity of Facilities
The basic design principle for the entire G.A.C. canal network was based on a 10-year
precipitation event. This particular sub-basin is the outlet for the entire Main Golden Gate
System and is a very vital part of the water management system for Collier County. Major
maintenance programs for this basin's canal network have been established by the Collier
County Stormwater Management Department and the Big Cypress Basin Board to control and
remove the excessive accumulations of aquatic vegetation and sediment when they begin to
hinder the flow of stormwater through the system. The County maintains the secondary
portions and the Big Cypress Basin maintains the primary portions.

A weir modification program has been established by the Big Cypress Basin Board. The main
goal of this renovation program was to provide the ability to maintain a higher normal flow water
elevation, especially for the winter “dry” season, but allow for greater flexibility in releasing
excessive amounts of stormwater in the summer “wet” season to prevent flooding.

The overall condition of the existing facilities is adequate to pass the design storm runoff for this
basin. The Basin continues to evaluate the weir and channel configurations so that the


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       Collier County Hazard Mitigation Plan                                              April 15, 2005



efficiency of the system will be improved as a water management tool to better meet the needs
for this area.

        Proposed Improvements
As mentioned in many of the above listed studies and reports, there is a need to improve the
Main Golden Gate Canal system so that it can function as a more efficient total water
management tool. Most of the planned improvements involve the modification of some of the
weirs so that they will have a raised control elevation for low flow discharge and also have a
built in capacity to discharge more stormwater when necessary during periods of high flow to
prevent flooding. Five weirs have already been so modified on the Main Golden Gate Canal,
with further modifications to the weirs and canal segments possible. The design and
construction of weir and channel segments, if needed, are included in the capital improvement
program of the County or the Big Cypress Basin.

A2. CYPRESS CANAL BASIN

      Description
The Cypress Canal Basin is located in the northeast portion of the Main Golden Gate System
and contains approximately 17 square miles of estates residential land. The Cypress Canal
Basin is bounded by the Cocohatchee River Canal to the north, the Main Golden Gate Canal to
the east, the Main Golden Gate Canal and 951 Canal Central to the south and the 951 Canal
Central and 951 Canal North to the west.

       Historical Background
Prior to the construction of the Cypress Canal Basin portion of the G.A.C. canal network, the
land was a mixture of undeveloped wetlands and uplands with almost no residential dwellings.
As the canals were constructed, a roadway system was also constructed by the G.A.C. to
provide access to the land for development purposes.

       Description of Existing Facilities
The existing facilities within this basin consist of approximately 9 miles of primary canal and no
secondary canal. There is 1 water level control structure (CYC-00-S0120) within this basin on
the primary canal system. This weir was totally reconstructed by the Basin in 1989 and later
modified in 1994. The main goal of these modifications was to provide the ability to maintain a
higher normal flow water elevation but allow for greater flexibility in releasing excessive amounts
of stormwater to prevent flooding. The flow of water within this basin is to the southwest and the
location of the described weir provides a controlled step-down of the water level to prevent the
over-drainage of the interior lands.

      Existing Condition/Capacity of Facilities
The Big Cypress Basin staff operates the canals and structure within this basin and maintains
them for aquatic vegetation and accumulated sediments removal as needed. The overall
condition of the existing facilities is adequate to pass the design storm runoff for this basin. The
Basin continues to evaluate the weir and channel configurations so that the efficiency of the
system will be improved as a water management tool to better meet the needs for this area.

     Proposed Improvements
There are no proposed capital improvements for the stormwater facilities within this basin.

A3. HARVEY CANAL BASIN



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       Description
The Harvey Canal Basin is located in the center portion of the Main Golden Gate System,
immediately north of and adjacent to the intensely developed area known as Golden Gate City.
This basin contains approximately 6 square miles of estates residential and urban residential
land. The Harvey Canal Basin is bounded by the Cocohatchee River Canal and I-75 Canal
basins to the north, the 951 Canal Central and 951 Canal North basins to the east, the Green
Canal Basin to the south, and the I-75 Canal Basin to the west. The Harvey Canal discharges
directly into the Green Canal.

       Historical Background
Prior to the construction of the Harvey Canal Basin portion of the G.A.C. canal network, the land
was a mixture of undeveloped wetlands and uplands with almost no residential dwellings. As
the canals were constructed, a roadway system was also constructed by the G.A.C. to provide
access to the land for development purposes.

      Description of Existing Facilities
The existing facilities within this basin consist of approximately 3 miles of secondary canal and
no primary canal. There are 2 water level control structures (D1C-00-S0120 and D1C-00-
S0140) within this basin on the secondary canal system. The weir (D1C-00-S0120) just north of
Golden Gate City was totally reconstructed by the Big Cypress Basin in 1993. The main goal of
this modification was to provide the ability to maintain a higher normal flow water elevation but
allow for greater flexibility in releasing excessive amounts of stormwater to prevent flooding.

       Existing Condition/Capacity of Facilities
The County Road Maintenance Department staff operates the canals and structures within this
basin and maintains them for aquatic vegetation and accumulated sediments removal as
needed. The overall condition of the existing facilities, except for upper half mile of the Harvey
Canal and the culvert beneath Pine Ridge Road, is adequate to pass the design storm runoff for
this basin. The County continues to evaluate the weir and channel configurations so that the
efficiency of the system will be sufficient as a water management tool to better meet the needs
for this area.

      Proposed Improvements
The reconstruction of the upper half mile of the Harvey Canal is being included as a capital
improvements connected with the proposed 6-laning of Vanderbilt Beach Road Extension. This
work should be completed in 2006.

A4. I-75 CANAL BASIN

      Description
The I-75 Canal Basin is located in the northwest portion of the Main Golden Gate Canal Basin
and is bound by the Airport Road Canal (S.) and Airport Road Canal (N.) Basins to the west, the
Main Golden Gate Canal Basin to the south and east, and the Cocohatchee River Basin to the
north. The total land area of this sub-basin is approximately 17 square miles and consists of
agriculture, residential estates, urban residential, and some commercial land use. The major
residential areas within this basin are the community of Golden Gate City, and the Wyndemere,
Kensington, Village Walk and Vineyards PUD's. This basin provides the drainage outlet for the
Harvey Canal Basin and the northern half of Golden Gate City through the Green Canal Basin.

      Historical Background



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The I-75 Canal Basin was created by the excavation of the G.A.C. canal network in the 1960's.
The northern boundary had been previously established by the construction of CR-846
(Immokalee Road). The eastern boundary was then created by the construction of CR-951.
The land within this sub-basin had historically drained in a southwesterly direction and the canal
network was constructed to follow this approximate pattern.

      Description of Existing Facilities
There are approximately 7 miles of primary canals and 6 miles of secondary canals within this
basin. There are also 3 water level control structures or weirs located at strategic points along
the primary canals to help prevent the over-drainage of the surrounding land. The I-75-1 Weir
(D2C-00-S0100) was constructed by the Big Cypress Basin in 1991 to replace the old D2-7 weir
farther upstream. A backpumping station was added to this weir in 1992. The County
constructed the I-75-2 weir in 1992 to replace the old D2-8 flashboard riser weir. In 1994 the
Basin added a backpumping station to this weir. The main feature of this canal network is the I-
75 Canal which outlets into the Main Golden Gate Canal a short distance upstream from Weir
No. GG-2 (MGG-00-S0120). The I-75 Canal receives the drainage from the northwestern
portion of this basin as well as the discharge from the Harvey Canal to the northeast and the
Green Canal to the east out of Golden Gate City.

     Existing Condition/Capacity of Facilities
The condition and capacity of the facilities within the I-75 Canal Basin varies from adequate to
inadequate. Generally speaking, the I-75 Canal is sufficiently able to pass the 10-year, 1-day
storm design runoffs while some of the feeder canals need improvements. The Big Cypress
Basin performs the maintenance and operation of the primary facilities within this basin while
the Collier County Road Maintenance Department is responsible for the secondary facilities.
Maintenance primarily consists of the control and removal of aquatic vegetation when this
becomes excessive and hinders the flow of stormwater through the system. Some sediment
removal work is also done to return the channel to its approximate original cross section when
excess sediment accumulations become a problem.

      Previous Studies
In addition to being included in the studies mentioned in the Main Golden Gate Canal System
section, two additional studies have been completed which concentrate specifically on the I-75
Canal Basin. The first study, "Hydrologic Effects of Storm of September 1-3, 1983 in Golden
Gate City, Collier County, Florida" was prepared for the Big Cypress Basin Board by Johnson
Engineering, Inc. in September, 1983. This report documented the extent of flooding and the
status of the drainage facilities at the time of the flooding. The intent of this report was to
document facts and no attempt was made to draw conclusions from the data.

A second study, "D-2 Canal Drainage System Study" was prepared as a joint effort by Hole,
Montes and Associates, Inc. and Johnson Engineering, Inc. in September, 1984. This study
was a follow up canal system capacity analysis utilizing much of the data obtained from the
previous report by Johnson Engineering, Inc. The recommendations to improve the water
management efficiency of this system included some canal channel renovation work, weir
modifications, and increased aquatic vegetation maintenance.

      Proposed Improvements
Many of the proposed improvements recommended by the above mentioned engineering
studies have been completed and no additional improvements are currently planned in a capital
improvement program.



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A5. GREEN CANAL BASIN

      Description
The Green Canal Basin is a small drainage area located in the southern portion of the Main
Golden Gate System. The basin consists of approximately 2 square miles of urban residential
and residential estates land use. The Green Canal Basin is bounded by the Harvey Canal
Basin to the north, by the 951 Canal Central Basin to the east, by the Main Golden Gate Canal
Basin to the south, and the I-75 Canal Basin to the west and northwest.

      Historical Background
The Green Canal Basin was created by the excavation of the G.A.C. canal network in the
1960's, including the northern area of Golden Gate City. The eastern boundary was created by
the construction of CR-951. The land within this sub-basin had historically drained in a
southwesterly direction and the canal network was constructed to follow this approximate
pattern.

      Description of Existing Facilities
There are approximately 3 miles of primary canals and 4 miles of secondary canals within this
basin. There are no weirs within the basin since water levels are controlled by the I-75-1 weir
(D2C-00-S0100).

        Existing Condition/Capacity of Facilities
The condition and capacity of the facilities within the Green Canal Basin are generally adequate.
The downstream 2 miles of primary canal are somewhat restrictive since they were never
excavated to their full planned cross section. The maintenance and operation of the primary
facilities within this basin are performed by the Big Cypress Basin while the Collier County Road
Maintenance Department is responsible for the secondary facilities. Maintenance primarily
consists of the control and removal of aquatic vegetation when this becomes excessive and
hinders the flow of stormwater through the system. Some sediment removal work is also done
to return the channel to its approximate original cross section when excess sediment
accumulations become a problem.

     Proposed Improvements
There are no proposed capital improvements for the stormwater facilities within this basin.

A6. AIRPORT ROAD CANAL SOUTH

      Description
The Airport Road Canal (S.) Basin is located near the western end of the Main Golden Gate
Canal and functions as a drainage outlet for the lands located along Airport-Pulling Road
between Vanderbilt Beach Road and Golden Gate Parkway. The canal along Airport-Pulling
Road is a single canal with a drainage divide located in the vicinity of the Vanderbilt Beach
Road intersection which separates the canal into two drainage basins. This basin of the canal
drains into the Main Golden Gate Canal a short distance upstream from Weir No. GG-1 on the
Main Canal. This basin is bound on the north by the Airport Road Canal (N.) Basin, on the west
by the Gordon River Basin, on the south by the Main Golden Gate Canal Basin, and on the east
by the I-75 Canal Basin. The total area of the basin is approximately 5 square miles.

Much of the land within this basin has been changed from agricultural to residential and/or
commercial use. Some of the residential and commercial developments that have been
completed or are presently under construction include Tall Pines, Lone Oak, World Tennis


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       Collier County Hazard Mitigation Plan                                           April 15, 2005



Center, Woodside Apartments, Orchards, Oxford Village (Timberwood), Pine Air Lakes, Citrus
Gardens, and Ridgeport Plaza. Several more PUD's are under various stages of design and
include, Bridget Lake, Vineyards, Orange Blossom, and Cypress Glen.

        Historical Background
        The Airport Road Canal South Basin was initially created by agricultural interests using
the fill material from the canal to construct the beginnings of what is now known as Airport
Pulling Road. The eastern basin boundaries were established by the construction of the Golden
Gate Canal system in the 1960’s. The natural drainage flow was to the south and southwest,
primarily into the Gordon River Basin. Construction of Airport Pulling Road directed the flow
south into what is now known as the Main Golden Gate Canal.

      Description of Existing Facilities
The main drainage feature of this sub-basin is the existing primary canal along the east side of
Airport-Pulling Road. This canal is approximately 5 miles in length and was originally excavated
to provide the fill material for the roadbed construction and drain the land east of the road.
There is one water level control structure located approximately one-half mile north of the
Golden Gate Parkway intersection. This structure has been modified by the Big Cypress Basin
Board to allow for the back-pumping of water into the canal behind it to maintain an elevated
groundwater and provide a recharge source for the underlying Coastal Ridge Aquifer.

       Existing Condition/Capacity of Facilities
Because of recent improvements made in conjunction with the 4-laning of Airport-Pulling Road,
the Airport Road Canal (S.) is in good condition to handle the storm runoff from this drainage
sub-basin. The maintenance of this canal is performed by the Big Cypress Basin and primarily
consists of the control and removal of aquatic vegetation when this becomes excessive and
hinders the flow of stormwater through the system. Some sediment removal work is also done
to return the channel to its approximate original cross section when excess sediment
accumulations become a problem.

       Proposed Improvements
The Big Cypress Basin has scheduled the reconstruction of the one water level control structure
in their 2005 capital improvement program. The pump installation modification to the one water
level control structure allows this sub-basin to work in conjunction with the Airport Road Canal
(N.) sub-basin water level control structure to maintain an increased water level for aquifer
recharge during periods of low rainfall.


A7. CORKSCREW CANAL BASIN

     Description
The Corkscrew Canal Basin is located in the northeast portion of the Main Golden Gate System
and contains approximately 10 square miles of estates residential and agricultural use land.
The Corkscrew Canal Basin is bounded by the Cocohatchee River Canal Basin to the north, the
Main Golden Gate Canal Basin and the Orange Tree Canal Basin to the east, the Main Golden
Gate Canal Basin to the south, and the Cypress Canal Basin and Cocohatchee River Canal
Basin to the west.

       Historical Background
Prior to the construction of the Corkscrew Canal Basin portion of the G.A.C. canal network, the
land was a mixture of undeveloped wetlands and uplands with almost no residential dwellings.


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       Collier County Hazard Mitigation Plan                                               April 15, 2005



As the canals were constructed, a roadway system was also constructed by the G.A.C. to
provide access to the land for development purposes.

      Description of Existing Facilities
The existing facilities within this basin consist of approximately 9 miles of primary canal and 1
mile of secondary canal. There is 1 water level control structures (CCB-00-S0100) on the
primary canal system that has just been reconstructed as a part of the Immokalee Road 6-
laning. A second structure (CCB-00-S0160) is located on the upstream side of 43rd Street NW
and was constructed by the County as a part of a wetland mitigation project. The flow of water
within this basin is to the south and the location of the described weirs provides a controlled
step-down of the water level to prevent the over-drainage of the interior lands.

      Existing Condition/Capacity of Facilities
The Big Cypress Basin staff operates the primary canals and structure within this basin and
maintains them for aquatic vegetation and accumulated sediments removal as needed. The
Collier County Road Maintenance Department operates and maintains the secondary
stormwater facilities. The overall condition of the existing facilities is inadequate to pass the
design storm runoff for this basin.

      Proposed Improvements
The Big Cypress Basin has contracted to replace several sets of culverted canal crossings with
bridges and is designing some canal segment reconstructions to provide increased capacity and
reduce maintenance requirements for the primary stormwater facilities within this basin.

A8. ORANGE TREE CANAL

      Description
The Orange Tree Canal Basin is located in the northeast portion of the Main Golden Gate
System and contains approximately 3 square miles of urban residential and estates residential
use land. The Orange Tree Canal Basin is bounded by the Corkscrew Canal Basin to the north
and west, the Main Golden Gate Canal Basin to the east, and the Main Golden Gate Canal
Basin to the south.

       Historical Background
Prior to the construction of the Orange Tree Canal Basin portion of the G.A.C. canal network,
the land was a mixture of undeveloped wetlands and uplands with almost no residential
dwellings. As the canals were constructed, a roadway system was also constructed by the
G.A.C. to provide access to the land for development purposes. The Orange Tree development
was originally proposed to be an urbanized area similar to Golden Gate City (described in the
Main Golden Gate Canal Basin section). The G.A.C. development efforts were not undertaken
within Orange Tree and only recently has the development been initiated utilizing current urban
design standards and golf course design. The lake systems within the Orange Tree
development, which forms the headwaters of the basin are maintained by the private
developer/homeowner associations.

     Description of Existing Facilities
The existing public facilities within this basin consist of approximately 3 miles of primary canal
and no secondary canal. There are no water level control structures within this basin on the
primary canal system. The flow of water within this basin is to the south

      Existing Condition/Capacity of Facilities


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       Collier County Hazard Mitigation Plan                                              April 15, 2005



The Big Cypress Basin staff operates the primary canal within this basin and maintains it for
aquatic vegetation and accumulated sediments removal as needed. The overall condition of the
existing facilities is adequate to pass the design storm runoff for this basin.

     Proposed Improvements
There are no proposed capital improvements for the stormwater facilities within this basin.

A9. 951 CANAL CENTRAL

     Description
The 951 Canal Central Basin is located in the northcentral portion of the Main Golden Gate
System and contains approximately 1 square mile of estates residential use land. The 951
Canal Cental is bounded by the 951 Canal North Basin to the north, the Main Golden Gate
Canal Basin to the east and south, and the Main Golden Gate Canal Basin, the Green Canal
Basin, and the Harvey Canal Basin to the west.

       Historical Background
Prior to the construction of the 951 Canal Central Basin portion of the G.A.C. canal network, the
land was a mixture of undeveloped wetlands and uplands with almost no residential dwellings.
As the canals were constructed, a roadway system was also constructed by the G.A.C. to
provide access to the land for development purposes. The existing CR-951 roadway has been
improved to a 4-Lane road in some places and the canal reshaped to provide adequate
capacity.

     Description of Existing Facilities
The existing public facilities within this basin consist of approximately 2 miles of primary canal
and no secondary canal. There is one water level control structure within this basin on the
primary canal system. The flow of water within this basin is to the south

       Existing Condition/Capacity of Facilities
The Big Cypress Basin staff operates the primary canal within this basin and maintains it for
aquatic vegetation and accumulated sediments removal as needed. The overall condition of the
existing facilities is adequate to pass the design storm runoff for this basin.

     Proposed Improvements
There are no proposed capital improvements for the stormwater facilities within this basin.

B.    DISTRICT NO. 6 SYSTEM

The District No. 6 System is a highly developed drainage area in the west central portion of
Collier County. It is identified by a previously established political boundary designation and
contains 6 separate drainage basins as follows:

      B1.    Rock Creek Basin
      B2.    C-4 Canal Basin
      B3.    Lely Canal Basin - Main
      B4.    Lely-Manor Canal Basin
      B5.    Haldeman Creek Basin
      B6.    Winter Park Outlet




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       Collier County Hazard Mitigation Plan                                            April 15, 2005



It is important to keep in mind that District No. 6 is not a single drainage basin and that it
contains individual basins that are described in the following sections. This area has been
extensively developed with PUD's that have created a considerable portion of the drainage
facilities within the various basins. However, due to the age differences of the developments,
not all of the drainage systems have been designed to work in unison or for the same design
storm standard. This area also contains large tracts of agricultural land use in its southern
portion that are rapidly being designed for development into urban residential and golf course
communities.

       Previous Studies
There are four studies in the Collier County Stormwater Management Department files that
provide information and recommendations on the needs and proposed corrective actions for
District No. 6 System with a primary focus on the Lely Canal Basin - Main, water management
system. The first study, "Master Plan for Water Management District No. 6, Collier County,
Florida" was prepared by Black, Crow and Eidsness, Inc. in February 1974. This report
discussed the drainage problems and also addressed the environmental concerns that were
being caused by the present method of dumping the freshwater from the Lely Canal directly into
the saltwater areas. A series of spreader waterways were proposed along with several water
level control structures to provide a controlled discharge into the estuaries and prevent the over
drainage of some upstream wetland preservation/conservation areas.

The "Proposed Lely Canal Water Control Structure, Collier County, Florida" engineering report
was prepared by CH2M Hill in December, 1978. This report proposed that a water level control
structure be constructed on the Lely Canal at the US-41 bridge crossing. The structure would
provide flooding and drainage control and conveyance of surface floodwater to the estuarine
zone as well as conservation of surface and groundwater in the drainage areas through
modulation of flow and subsequent storage of surface and groundwater in the dry season.

The "Lely Outfall Surface Water Management System (Preliminary Design)" report was
prepared by CH2M Hill in December, 1979, as a follow up to their previous report. This new
report described the proposed Lely Canal improvements and spreader waterway including the
general layout and design of the facilities, environmental and maintenance factors in the system
performance and costs of construction and maintenance of the facilities.

The most recent study is the "Master Plan Update for Water Management District No. 6"
prepared by Wilson, Miller, Barton, Soll, and Peek, Inc. in October, 1985. The purpose of the
study was to re-evaluate the original master plan prepared in 1974. The report describes a
proposed plan of water management for District No. 6 that is designed to provide a mechanism
of flood control for the existing and future developments in the area. This plan is designed to
complement the Stormwater Management standards of Collier County and the South Florida
Water Management District. It addresses environmental considerations such as protection of
groundwater levels, elimination of point discharges into estuarine areas, and protection of
freshwater wetlands. To obtain the environmental permits necessary to construct the
improvements proposed by this report, the County has been working continually since 1988 to
get State and Federal approvals. In 2004 the South Florida Water Management District issued
a permit for a project called the Lely Area Stormwater Improvement Project (LASIP). This
project addresses only the Main Lely Canal Basin and the Lely Manor Canal Basin
improvements. As a part of the LASIP, approximately 110 acres of wetlands with a few
scattered uplands have been acquired for preservation within the project’s boundaries. The
County continues to work toward the federal permitting approval.



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       Collier County Hazard Mitigation Plan                                             April 15, 2005



B1.   ROCK CREEK BASIN

      Description
The Rock Creek Basin is a small drainage area in the northwest corner of the District No. 6
Area. This basin is bound by the Main Golden Gate System to the north, the City of Naples to
the west, the Haldeman Creek Basin to the south, and the Lely Canal Basin - Main to the east.
It consists of approximately 3 square miles of predominantly residential dwelling urban land use
with a considerable amount of commercial land use along Davis Blvd., Radio Road and Airport-
Pulling Road. The older areas of development include the Brookside and Coconut Creek
subdivisions. In addition, the Springwood, Westview Plaza, and Foxfire, Regency Autohaus,
and Summerwood PUD's have been constructed. Only the lower end of Rock Creek is within
the Naples city limits and this portion is tidally influenced by Naples Bay.

       Historical Background
The Rock Creek Basin is one of the older developed urban regions east of Naples Bay. The
historical basin boundary for Rock Creek has been reduced by the construction of the various
roads and the G.A.C. canal network. This region has experienced years of development activity
with piecemeal drainage conveyance channels excavated by the individual development and
road construction activities.

       Description of Existing Facilities
The main drainage feature of this basin is the natural Rock Creek drainage channel that is
approximately 2 miles in length. Extensive residential development along the lower reaches of
this creek has also reduced the size of the available historic flood plain. Approximately 4 miles
of secondary canals have been excavated within this basin to provide drainage for the various
developments. There is one existing water level control structure that acts as a salinity barrier
for Rock Creek. Due to the small size of the basin, all of the drainage facilities are considered
as secondary instead of primary.

      Existing Condition/Capacity of Facilities
Many of the drainage control facilities within this basin have been in existence for many years
as a result of various development projects. The maintenance of the public drainage facilities is
performed by the Collier County Road Maintenance Department and primarily consists of the
control and removal of aquatic vegetation when this becomes excessive and hinders the flow of
stormwater through the system. Some sediment removal work is also done to return the
channel to its approximate original cross section when excess sediment accumulations become
a problem. The lower end of the Rock Creek channel is being evaluated for a sediment and
debris removal project. Once cleaned it is generally sufficient to provide for the flood protection
needs of this basin, but approximately one third of the constructed drainage channels are
inadequate and need renovation and/or modification.

     Proposed Improvements
There are no proposed capital improvements for the stormwater facilities within this basin.

B2.   C-4 CANAL BASIN

      Description
The C-4 Canal Basin is located along the southeastern boundary of the District No. 6 System.
This basin is approximately 6 square miles in area and consists of proposed and actively
developing residential and recreational land uses. It is bound by the Lely Canal Basin - Main to
the north and northwest, the Lely-Manor Canal Basin to the west, the Rookery Bay estuary to


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       Collier County Hazard Mitigation Plan                                              April 15, 2005



the south, and the Henderson Creek Basin to the east. The major active developments within
this basin include Lely Resort Community, Eagle Creek, and Shadowwood. Several more
PUD's are in various stages of planning and/or approval for construction

      Historical Background

The C-4 Canal Basin derived its name from the channel numbering system developed in the
1985 "Master Plan Update for Water Management District No. 6" study prepared by Wilson,
Miller, Barton, Soll and Peek, Inc. This basin contained large areas of undeveloped uplands
and wetlands as well as former agricultural lands. A key feature is the Rattlesnake Hammock
slough that serves to transport surface water in a southwesterly direction along the western
edge of this basin. This basin is currently undergoing extensive development activity and new
developments are being proposed for the remaining undeveloped lands. The basin boundaries
were created by the construction of roads and adjacent development berms.

      Description of Existing Facilities
Much of the northern half of the basin is the Lely, A Resort Community development which is
designed to receive the basin’s stormwater runoff and route it through a lake system with an
ultimate discharge into the C-4 Canal south of US-41. Stormwater that does not enter the Lely,
A Resort Community system is collected by a canal along the north side of US-41 and flows
southeastward to the C-4 Canal. The stormwater then flows southward through the Eagle
Creek PUD until it empties into the lower reaches of Henderson Creek. A water level control
structure has been constructed at the Tower Road Crossing. This structure has three slide
gates to control the canal water level and it also functions as a salinity control structure. There
is a small roadside ditch along the east side of Barefoot Williams Road that also empties into
Henderson Creek. There are approximately 2 miles of publicly maintained secondary canal in
this basin.

       Existing Condition/Capacity of Facilities
The roadside ditch along the north side of US-41 and the Lely, A Resort Community lake
system are the primary collectors of runoff for this basin. This roadside ditch along US-41 has
been in existence for many years and periodically receives maintenance work to remove flow
restrictions prior to discharging into the C-4 Canal. The C-4 Canal was reconstructed as a part
of the Lely Resort Community PUD from US-41 to the point where it enters the limits of the
Eagle Creek PUD near Price Street. As a part of the Eagle Creek PUD drainage development
work, the C-4 Canal was widened and a water level control structure installed at the Tower
Road crossing. These improvements to the C-4 Canal provided a salinity barrier and a means
to control fresh water discharge into Henderson Creek. The maintenance of the drainage
system within this basin is performed by the Collier County Road Maintenance Department and
primarily consists of the control and removal of aquatic vegetation when this becomes excessive
and hinders the flow of stormwater through the system. Some sediment removal work is also
done to return the channel to its approximate original cross section when excess sediment
accumulations become a problem. Additionally, the maintenance personnel of the Eagle Creek
development maintain the portion of the C-4 Canal that flows through their property. As a
whole, the drainage systems within this basin are good, but need improvements in some
sections to allow for the adequate passage of desired design flows.

     Proposed Improvements
There are no proposed capital improvements for the stormwater facilities within this basin.

B3.   LELY CANAL BASIN - MAIN


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       Collier County Hazard Mitigation Plan                                              April 15, 2005




       Description
The Lely Canal Basin - Main is another large drainage basin within the District No. 6 System
and includes the land areas from the southwestern corner through the central portion to the
northeast corner. The basin is approximately 9 square miles in size and contains residential
development, commercial, recreational, and undeveloped land uses. It is bound by the Golden
Gate Basin to the north, the Rock Creek and Haldeman Creek Basins to the west, the Dollar
Bay and Rookery Bay estuaries to the southwest, the Lely-Manor Canal Basin to the south, the
C-4 Canal Basin to the southeast and the Henderson Creek Basin to the east. Most of the
residential development in this basin has occurred in the southwest and central portions near
US-41 while the northeast corner has recently been the location of several development
activities. Some of the PUD's that have been or are being developed include Wildwood Estates,
Berkshire Lakes, Naples Lake (Moon Lake), West Crown Pointe (Loch Louise), Huntington
Woods, Sabal Lakes, Youth Haven, Riviera Colony Golf Estates, Lely Country Club, Brettone
Park (Glen Eagle), Crown Pointe, Shamrock Country Club (Naples Heritage), Royal Wood Golf
and Country Club, and East Naples Community Park. Some of the PUD's that are under
various stages of design and/or approval but have not begun construction include Twelve Lakes
(Madison Park) and Collier DRI (Villages of Sabal Bay). In addition to the PUD's, several older
subdivisions and/or residential areas have been built including Lely Golf Estates, Lely Villas,
Naples South, Riviera Colony, Naples Mobile Home Estates, Oak Hill Estates, and Pine View
Villas.

       Historical Background
Prior to the construction of any drainage systems in Collier County, the Lely Canal Basin - Main
was not identifiable as a separate system but was a part of a large coastal outfall system for
waters flowing from the northeast. With the construction of US-41 to the south, CR-951 to the
east and CR-856 (Radio Road) to the north, the upstream boundaries of this basin were
established and the historical sheetflow of surface water was altered greatly. As the large
residential and recreational developments began to be built in this basin, they excavated small,
shallow drainage canals to drain the land surface. Many of these developments allowed
residential structures to be built at natural grade elevations and did not consider the contributory
drainage effects from off-site lands. This created flooding situations when the small canal
systems were not able to sufficiently pass the volumes of water that occurred within the limits of
the entire Lely Canal Basin - Main.

      Description of Existing Facilities
As previously mentioned, most of the existing drainage facilities have been constructed as a
part of the numerous residential and recreational developments within the basin. There are
approximately 5 miles of secondary canals and no publicly maintained water level control
structures. Due to the extensive residential development in the areas of the canals, there are
many canal road crossings.

      Existing Condition/Capacity of Facilities
Most of the existing secondary drainage facilities are within the older developed areas and
generally are not adequate to provide an acceptable degree of flood protection. The newer
developments, and those now being proposed, have been designed using current water
management design standards and provide adequate protection for their internal drainage
needs. However, the overall canal system needs improvement to increase the efficiency of the
water management capabilities and provide increased flood protection for the entire basin. The
maintenance of the public drainage facilities within this basin is performed by the Collier County
Road Maintenance Department and primarily consists of the control and removal of aquatic


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       Collier County Hazard Mitigation Plan                                             April 15, 2005



vegetation when this becomes excessive and hinders the flow of stormwater through the
system. Some sediment removal work is also done to return the channels to approximate
original cross section when excess sediment accumulations become a problem. Maintenance
of the private drainage facilities is the responsibility of the owners.

       Proposed Improvements
The previously mentioned reports clearly indicate the need to improve the efficiency and
manageability of the water management system within the Lely Canal Basin - Main. To help
meet these needs, the County has undertaken efforts to implement some of the
recommendations of the Water Management District No. 6 study mentioned previously. The
County has been working since 1988 to obtain the necessary environmental permits for
improvements to the secondary canals within the Lely Canal-Main Basin. The proposed
improvements include the construction of a spreader lake at the outfall of the Lely Canal - Main
into the estuary to control and distribute the fresh water entering the salt water system at the
downstream end of the main canal, construct several water level control structures with
operable gates, and improve the conveyance capacity of the secondary canal system as well as
construct new canal reaches where needed. In 2004 the South Florida Water Management
District issued their Environmental Resource Permit for the proposed work, and the County
continues working toward obtaining the approved U.S. Army Corps of Engineers permit.

B4.   LELY-MANOR CANAL BASIN

      Description
The Lely-Manor Canal Basin is a drainage area of approximately 8 square miles located to the
southeast of the Lely Canal Basin. The most portions of the basin north of US-41 have been
developed for residential usage. There is also some residential development for a short
distance south of US-41 while the southern and eastern portions of the basin are undeveloped
coastal wetlands and mangrove forests. This basin is bound by the Lely Canal Basin to the
north and west , the Rookery Bay estuary to the south, and the C-4 Canal Basin to the east.
The ground elevations are generally low and the basin is subject to frequent local flooding
problems. The major development within this basin is the Naples Manor subdivision. The Lely
Palms PUD and a portion of the Lely Country Club PUD have been completed and the Lely
Square, Lely R. & D. Park, Wentworth Estates and Collier DRI (Villages of Sabal Bay) PUD's
are in various stages of design and/or approval for construction.

       Historical Background
Prior to the construction of any drainage systems in Collier County, the Lely-Manor Canal Basin
was not identifiable as a separate system but was a part of a wetland sough that transported
surface water flowing from the northeast. With the construction of US-41 to the south, CR-951
to the east, SR-84 (Davis Blvd.) to the north, and the older portions of the Lely residential
development area to the west, the boundaries of this basin were established and the historical
sheetflow of surface water was altered greatly. As the residential subdivision known as Naples
Manor began to be built in the middle of the slough that transects this basin, small, shallow
drainage canals and swales were excavated to drain the land surface. Most of this subdivision
was built at or near natural grade elevations and did not consider the low ground elevations of
the slough. This created flooding situations when the upstream and downstream portions of the
remaining slough filled with surface water. Additionally, the small canal systems were not able
to sufficiently pass the volumes of surface water that occurred within the limits of the Lely-Manor
Canal Basin.

      Description of Existing Facilities


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       Collier County Hazard Mitigation Plan                                            April 15, 2005



The drainage facilities that have been constructed for the Lely-Manor Basin consist of a network
of shallow ditches, swales, and small canals. These facilities were constructed in much the
same manner as described for the early drainage control canals for the Lely Basin. Since the
land is low in elevation, the surface water runoff from the basin is very slow in draining through
the shallow channels and therefore causes the frequent flooding as previously mentioned. The
outlet ends of the canals also do not have spreaders to evenly distribute the fresh water into the
salt water.

      Existing Condition/Capacity of Facilities
The condition and capacity of the drainage facilities within this basin are generally not adequate
to provide a desirable degree of flood protection. Many of the canals need to be deepened
and/or widened to improve the hydraulic efficiency of the system. Maintenance is systematically
performed by the Collier County Road Maintenance Department and primarily consists of the
control and removal of aquatic vegetation when this becomes excessive and hinders the flow of
stormwater through the system. Some sediment removal work is also done to return the
channel to its approximate original cross section when excess sediment accumulations become
a problem.

       Proposed Improvements
The previously mentioned engineering reports clearly indicate the need to improve the efficiency
and manageability of the water management system within the Lely Manor Basin. To help meet
these needs the County has undertaken efforts to implement some of the recommendations of
the Water Management District No. 6 study. The County has been working since 1988 to obtain
the necessary environmental permits for improvements to the secondary canals within the Lely-
Manor Canal Basin. The proposed improvements include the construction of spreader lakes at
the eastern and western outfalls of the Lely-Manor Canals into the estuary to control and
distribute the fresh water entering the salt water system at the downstream end of the main
canal, construct several water level control structures with operable gates, and improve the
conveyance capacity of the secondary canal system as well as construct new canal reaches
where needed. In 2004 the South Florida Water Management District issued their
Environmental Resource Permit for the proposed work, and the County continues working
toward obtaining the approved U.S. Army Corps of Engineers permit. Additionally, the proposed
plan incorporates the construction of a stormwater pump station to lift fresh water into an
existing wetland slough prior to discharging into the estuary to control and distribute the fresh
water entering the salt water system

B5.   HALDEMAN CREEK BASIN

      Description
The Haldeman Creek Basin is another small drainage area in the west and northwest portion of
the District No. 6 Area. It is approximately 3 square miles in area and is bound by the Rock
Creek Basin to the north, the Naples Bay estuary to the west, and the Lely Canal Basin-Main to
the northeast and southeast. This basin is highly developed for residential and commercial use
in accordance with the urban land use designation. Some of the existing developments include
the completed Glades and Lakewood subdivisions, the Cricket Lake, Pinebrook Lakes, Winter
Park, Largo Verde (Queens Park), Collier (Courthouse Shadows) and Kings Lake PUD's, the
Collier County Government Center, the Town Center and Town Center South shopping plazas.
There is also extensive commercial development along US-41 and Airport-Pulling Road.

      Historical Background



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       Collier County Hazard Mitigation Plan                                             April 15, 2005



The Haldeman Creek Basin was created by the constuction of residential developments as the
Naples community began to expand eastward in the 60’s and 70’s. Haldeman Creek is a
natural channel that has been dredged and altered years ago. A lack of maintenance has
allowed the channel to become restricted by sediments southwesterly of US-41. Upstream of
US-41, the channel depth was generally terminated when developers encountered a hard rock
strata which results in a varying channel profile. Existing culverted road crossings of the
channel take on many configurations.

      Description of Existing Facilities
Although the area of this basin is small, there are approximately 3 miles of secondary canals
and channels that have been constructed in accordance with the numerous residential and
commercial developments. These discharge into the natural Haldeman Creek channel which
discharges into Naples Bay. There is one County maintained water level control structure in
Haldeman Creek at the US-41 crossing which functions as a salinity barrier. A second County
maintained water level control structure is located near the Lakewood Country Club which is a
part of the Lakewood subdivision. An earthen weir has also been constructed as a part of the
Lake Kelly Outfall Ditch to prevent saltwater intrusion into the old Lake Kelly pit. This weir is
also maintained by the County.

      Existing Condition/Capacity of Facilities
The condition of the various facilities within this basin varies considerably depending on the age
and location. Maintenance is performed by the Collier County Road Maintenance Department
and/or the various homeowner associations of the residential developments. The maintenance
primarily consists of the control and removal of aquatic vegetation when this becomes excessive
and hinders the flow of stormwater through the system. Some sediment removal work is also
done to return the channel to its approximate original cross section when excess sediment
accumulations become a problem. Most of the water management facilities that have been
constructed in accordance with the newer developments are sufficient to pass the design storm
flows. The drainage facilities for the older developments, which often form the main canal
connectors to Haldeman Creek, are generally of insufficient capacity. Additionally, the lower
portion of Haldeman Creek has become restricted by excessive sediment deposition.

     Proposed Improvements
The County is in the midst of a design and permitting effort for removing sediments in the main
Haldeman Creek channel downstream of US-41. It is anticipated that dredging operations will
be contracted during 2005.

B6.   WINTER PARK OUTLET BASIN

      Description
The Winter Park Outlet Basin is a very small drainage area in the west portion of the District No.
6 Area. It is approximately 0.3 square miles in area and is bound by the Rock Creek Basin to
the north and west, and the Haldeman Creek Basin to the east and south. The Winter Park
Outlet Basin discharges into the Haldeman Creek Basin but is considered a separate basin.
This basin is highly developed for residential and commercial use in accordance with the urban
land use designation. Some of the existing developments include a portion of the completed
Glades subdivision, the Winter Park PUD, portions of the Collier County Government Center,
and the Home Depot and Wal-Mart retail establishments.

      Historical Background



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       Collier County Hazard Mitigation Plan                                           April 15, 2005



The Winter Park Outlet Basin is another drainage basin that was created by development
activities. In similar fashion to the Haldeman Creek Basin, the Winter Park Outlet Basin channel
is very small and shallow with older residences adjacent to it. This basin has seen newer
development activities in the headwaters that incorporate modern stormwater design practices.

      Description of Existing Facilities
Although the area of this basin is small, there is approximately 1 mile of secondary canal and
channels that have been constructed in accordance with the various residential and commercial
developments. There is one County maintained water level control structure at the point of
basin discharge into Haldeman Creek a short distance upstream from US-41.

       Existing Condition/Capacity of Facilities
The condition of the channels within this basin varies considerably depending on the age,
location, and degree of involvement in maintenance by the developments and included golf
course. Maintenance is performed by the Collier County Road Maintenance Department and/or
the various homeowner associations of the residential developments. The maintenance
primarily consists of the control and removal of aquatic vegetation when this becomes excessive
and hinders the flow of stormwater through the system. Some sediment removal work is also
done to return the channel to its approximate original cross section when excess sediment
accumulations become a problem.

      Proposed Improvements
There are no improvements planned within this basin at this time. Current County efforts to plan
improvements within the District No. 6 Area are focused within previously mentioned basins.
Assuming that current efforts are implemented, attention could then focus on other basins within
the District No. 6 area.

C.   COCOHATCHEE RIVER SYSTEM

The Cocohatchee River System encompasses a large basin of land in the north and
northwestern portion of Collier County. The western portion of the region is within the urban
designated area and is undergoing rapid development activity for both residential and
commercial usage. The eastern portion of the region is generally undeveloped or used for rural
and agricultural activities. There are extensive areas of wetlands within this region that also
include portions of the Corkscrew Regional Ecosystem Watershed (CREW) acquisition project
being undertaken by the South Florida Water Management District. The Cocohatchee River
System contains 7 separate drainage basins as follows:

     C1.     Cocohatchee River Basin
     C2.     Pine Ridge Canal Basin
     C3.     Palm River Canal Basin
     C4.     West Branch Cocohatchee River Basin
     C5.     East Branch Cocohatchee River Basin
     C6.     Airport Road Canal North Outlet
     C7.     951 Canal North Basin

     Previous Studies
A search of the Collier County Stormwater Management Department files identified two major
engineering studies that had been prepared for this drainage basin area. The first report,
"Master Plan, Water Management District No. 7 including the Cocohatchee and Gordon River
Basins, Collier County, Florida" by Black, Crow and Eidsness, Inc. in March, 1975, identified the


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       Collier County Hazard Mitigation Plan                                              April 15, 2005



drainage needs for the northern and western portions of the County. A second study,
"Cocohatchee Canal Salinity Control Structure Hydrologic Report" by Gee and Jensen
Engineers-Architects-Planners, Inc. in October, 1981, specifically addressed the size of the
main canal watershed and the need to construct a water level control structure near the western
end of this canal to prohibit the intrusion of salt water into the freshwater system and
groundwater. Both of these reports were principally concerned with the drainage of stormwater
from the basin and did not address the environmental effects to the downstream receiving
waters that now need to be considered in the basin design process.

In addition to the two above mentioned studies, two additional studies relating to groundwater
sources in this area were prepared by Missimer and Associates, Inc. The first study, entitled
"Groundwater Resources of the Cocohatchee Watershed, Collier County, Florida", was
principally concerned with the Coral Reef Aquifer and discussed the effects that the
Cocohatchee River Main Canal had on the available groundwater. This report showed that the
canal lowered the groundwater levels and proposed that a water level control structure be
constructed to increase the storage of groundwater and decrease the intrusion of salt water into
the aquifer system.

A second report by Missimer and Associates, Inc. entitled "Hydrogeologic Information on the
Water-Table Aquifer Adjacent to the Proposed Control Structure on the Cocohatchee Canal,
Collier County, Florida", took a more detailed look at the effects of the construction of a water
level control structure proposed in the "Groundwater Resources of the Cocohatchee
Watershed" report. While this report presented the same favorable discussion on the effects of
the water level control structure as a salinity control structure and the benefits of increasing the
groundwater storage, it also described some of the downstream effects that could be expected
to occur, especially the increase in salinity of the Cocohatchee River during the dry season.
This report also encouraged the use of additional upstream water level control structures to help
in the recharge of the Coral Reef Aquifer during the dry season.

C1.   COCOHATCHEE RIVER BASIN

      Description
The Cocohatchee River Basin is a large watershed area located in the north and northwest
section of the County. The total area of the basin is approximately 138 square miles and
functions as the outfall basin for the Cocohatchee River System. Subsequent to the completion
of the Stormwater Management Master Plan, staff from the Collier County Stormwater
Management Department has identified two small sub-basins within the urban area of this
basin. These two sub-basins are the Imperial Drainage Outlet with an area of approximately 4.4
square miles and the Imperial/FPL sub-basin with an area of approximately 0.4 square miles

Due to the existing natural drainage patterns of the extensive wetlands along the Collier County
northern border, including the Corkscrew Swamp, there are several areas where rainfall runoff
from Lee and Hendry Counties flows into Collier County and other areas where the runoff from
Collier County flows into Lee and Hendry Counties. The “Collier County Drainage Subbasins
Map” included in this Floodplain Management Plan identifies the locations of these areas as
they affect the existing drainage basins of Collier County. The proportionate capacity of runoff
contributed by these inter-County exchange areas is unknown and was estimated by the Collier
County Stormwater Management Master Plan. As a part of their evaluation of the Collier
County watershed, the Big Cypress Basin staff has developed more detailed information that
was input into their computer modeling efforts to quantify the available surface water resources
as a part of their stormwater facility improvements within this basin.


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       Collier County Hazard Mitigation Plan                                            April 15, 2005




This basin contains a variety of land uses including agriculture, vested residential (estates),
urban residential, and conservation/preservation area. Much of the recent residential
development in this basin has been in the form of planned unit developments (PUD's) including
Imperial West, Imperial Lakes, Quail II, Quail West, Huntington, Woodlands, Regency Village,
Mediterra, Tuscany Cove, Del a Sol, Carlton Lakes, Willoughby Gardens, Longshore Lake,
Northbrooke Plaza, Parklands, Dove Pointe, Olde Cypress, Heritage Bay, Bonita Bay, and Twin
Eagles. The PUD's are designed to incorporate a water management plan as a part of their
construction standards. These water management plans utilize the latest design storm
standards as required by the local regulatory agencies. Other developments within the basin
include Imperial Golf Estates, Willoughby Acres, Quail Creek, and Sleepy Hollow. The
Corkscrew Swamp Sanctuary is located in the northwest corner of the basin.

       Historical Background
The major stormwater management facility within this basin is the canal along the north side of
Immokalee Road (CR-846). This canal was dug many years ago as a linear borrow pit to
provide fill material for the construction of the road connecting Naples and Immokalee. The
canal was not sized for any specific conveyance capacity, and for the most part was just
scraped down to the rock layer. During the course of road construction, cross culverts were
periodically installed to allow for sheetflow from the north to south through existing wetlands.
Agricultural activities in the upland areas have for years utilized dikes and pumps to protect
fields from flooding. The large Corkscrew Swamp wetland area is still a major source of water
resources for the entire basin.

       Description of Existing Facilities
There are approximately 11 miles of primary canal and 4 miles of secondary canal within this
basin. The major stormwater management facility is the borrow canal created by the
construction of Immokalee Road. These canals help direct the flow of the surface drainage
toward the Cocohatchee River which outlets into the Gulf of Mexico through Wiggins Pass. In
the late 1990’s and early 2000’s, the Big Cypress Basin undertook a series of capital
improvement projects to reconstruct the Cocohatchee River Canal, install three water level
control structures, and replace several bridges to provide greater stormwater management and
flood control capabilities.

      Existing Condition/Capacity of Facilities
The Cocohatchee River Main Canal (Immokalee Road Borrow Canal) has been in existence for
many years. The operation and maintenance of this primary canal is performed by the Big
Cypress Basin. Operation and maintenance of the secondary canals is performed by Collier
County Road Maintenance Department and primarily consists of the control and removal of
aquatic vegetation when this becomes excessive and hinders the flow of stormwater through the
system. Some sediment removal work is also done to return the channels to their approximate
original cross section when excess sediment accumulations become a problem. The freshwater
portions of the Cocohatchee River Main Canal have been enlarged by the Big Cypress Basin to
be of generally sufficient size to pass the design storm runoff.

      Proposed Improvements
In conjunction with the previously mentioned engineering studies, the Big Cypress Basin has
undertaken the task of making improvements to the Cocohatchee River Main Canal. These
improvements are complete and no additional capital work is currently proposed These facility
improvements have also been coordinated with ongoing roadway improvements to CR-846 by
the County.


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       Collier County Hazard Mitigation Plan                                            April 15, 2005




The County designed and constructed improvements to the secondary facilities within the
Imperial/FPL sub-basin and has recently completed a Master Plan analysis within the Imperial
Drainage Outlet sub-basin. It is anticipated that construction on some of the improvements
identified in this Master Plan will be initiated in 2005.

C2.   PINE RIDGE CANAL

      Description of Basin
The Pine Ridge Canal Basin is located at the southwest corner of the Cocohatchee River Basin
and encompasses the northern half of the residential area known as Pine Ridge Subdivision as
well as all land between Pine Ridge and CR-846. The drainage area is bounded by the
Cocohatchee River to the north, US-41 to the west, a natural drainage divide through the Pine
Ridge subdivision to the south, and Goodlette-Frank Road to the east. The total area of the
basin is approximately 4 square miles.

      Historical Background
The Pine Ridge Canal Basin was established many years ago by the construction of a railroad
and US-41. During the development of the Pine Ridge subdivision, the canal, then known as
the North Naples Drainage Canal, was excavated to provide drainage relief. This canal was
greatly modified in 1993 by construction activities within the Pelican Marsh PUD. Portions of the
canal have now been connected to small lakes or enclosed in pipes and covered with a restored
wetland system as part of the development’s environmental mitigation measures.

      Description of Existing Facilities
The major drainage facilities for this basin are approximately 2 miles of secondary canal and
large storm drains. There are two water level control structures to prevent over drainage of the
basin.

      Existing Condition/Capacity of Facilities
Due to the relatively small area of this drainage basin and the favorable gradient of the existing
canal and structures, the facilities are of generally sufficient size to pass the design storm
runoffs. Outside the boundaries of the Pelican Marsh PUD, the maintenance of this canal is
performed by the Collier County Road Maintenance Department and primarily consists of the
control and removal of aquatic vegetation when this becomes excessive and hinders the flow of
stormwater through the system. Some sediment removal work is also done to return the
channel to its approximate original cross section when excess sediment accumulations become
a problem. The County also operates and maintains the two control structures.

     Proposed Improvements
There are no plans for any major improvements within this basin.

C3.   PALM RIVER CANAL

      Description of Basin
The Palm River Canal Basin is located to the south of the Imperial Drainage Outlet Sub-Basin of
the Cocohatchee River Basin and includes the residential area known as Palm River Estates.
The drainage area is approximately 1.5 square miles and is bound by the Imperial Drainage
Outlet Sub-Basin to the north and the Cocohatchee River Canal Basin to the west, south, and
east.



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       Collier County Hazard Mitigation Plan                                             April 15, 2005



      Historical Background
The boundaries of the Palm River Canal Basin were established by the development of the
residential communities of Palm River Estates and Imperial Golf Course Estates. As Palm River
Estates was developed, the southern branch of a natural stream, Horse Creek, was channelized
through the middle of the development to create what is now called Palm River. The northern
branch of Horse Creek has also been somewhat channelized, though on a much smaller scale,
and forms the dividing drainage channel between Palm River Estates and Imperial Golf Course
Estates. A small weir structure made from sheet piles was also constructed on the Palm River
to restrict salt water intrusion.

      Description of Existing Facilities
The original drainage feature within the basin is the Palm River. Beginning in the northeast
corner of this basin, the drainage flows toward the southwest through a series of shallow
wetland drains, similar to a slough, until it develops into an identifiable streamflow known as the
Palm River. There are approximately 1.5 miles of secondary canal within this basin. The sheet
pile weir structure was reconstructed by the Big Cypress Basin several years ago and then the
operation and maintenance responsibility turned over to the County.

      Existing Condition/Capacity of Facilities
The condition of the drainage facilities within this basin is generally good. The outlet end of the
primary canal is subject to tidal influence and thus the water level fluctuates accordingly. The
sheet pile water level control structure uses stop logs to regulate the upstream water elevations.
The operation and maintenance of this weir and canal is performed by the Collier County Road
Maintenance Department. Canal maintenance primarily consists of the control and removal of
aquatic vegetation when this becomes excessive and hinders the flow of stormwater through the
system. Some sediment removal work is also done to return the channel to its approximate
original cross section when excess sediment accumulations become a problem.

       Proposed Improvements
The Stormwater Management Department completed the North Livingston Road Master Plan
that identified needed improvements in both the Palm River Canal and Imperial Drainage Outlet
basins. The design and construction of these improvements will occur over the next few years
as funding is provided and some drainage easements are obtained and dedicated to the
County.

C4.   WEST BRANCH COCOHATCHEE RIVER BASIN

      Description of Basin
The West Branch Cocohatchee River Basin is located south of the Cocohatchee River Canal
Basin and immediately east of the Pine Ridge Canal Basin. The drainage area is approximately
0.5 square miles and is bound by the Cocohatchee River Canal Basin to the north, the Pine
Ridge Canal Basin to the west and south, and the Airport Road Canal North Basin to the east.
Most of the land is used for the County’s North Wastewater Treatment Plant and the Victoria
Park subdivision at the southern end of this basin.

      Historical Background
The West Branch Cocohatchee River Basin utilizes a natural channel that was once part of the
south branch of Horse Creek to convey surface water northward into the Cocohatchee River
Basin. The boundaries of the basin were established by agricultural operations in the area
many years ago. Recent developments have converted the agricultural fields into residential or
commercial properties.


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       Collier County Hazard Mitigation Plan                                            April 15, 2005




       Description of Existing Facilities
This basin is generally a natural drainage basin centered around the West Branch of the
Cocohatchee River. The natural stream bed has been greatly modified through channelization,
construction of small lakes and stream enclosure into storm drain pipes. The length of the
flowpath is approximately 1 mile in length and produces a northward flowing stream that
effectively removes the excess stormwater. Due to the small size and location of the drainage
area, the system is classified as a secondary system. One water level control structure has
been constructed in this stream bed to keep the groundwater level sufficiently high and to
prevent the tidal inflow of salt water.

      Existing Condition/Capacity of Facilities
The condition of this drainage system is adequate to meet the drainage needs of this basin and
therefore no major work is proposed for improvements. The operation and maintenance of this
drainage system is performed by the Collier County Road Maintenance Department. This
consists of the control and removal of aquatic vegetation near the water level control structures
when this becomes excessive and interferes with the operation of the structures as well as
performing routine maintenance on the downstream structure.

     Proposed Improvements
There are no plans for any major improvements within this basin.

C5.   EAST BRANCH COCOHATCHEE RIVER BASIN

      Description of Basin
The East Branch Cocohatchee River Basin is located south of the Cocohatchee River Canal
Basin and immediately east of the West Branch Cocohatchee River Basin. The drainage area
is approximately 0.6 square miles and is bound by the Cocohatchee River Canal Basin to the
north, the West Branch Cocohatchee River Basin to the west and south, and the Airport Road
Canal North Basin to the east. Most of the land is developed within the Southhampton, and
Surry Place PUD’s.

       Historical Background
The East Branch Cocohatchee River Basin utilizes an ill-defined natural channel that was also
once part of the south branch of Horse Creek to convey surface water northward into the
Cocohatchee River Basin. The boundaries of the basin were established by agricultural
operations in the area many years ago. Recent developments have converted the agricultural
fields into residential or commercial properties.

      Description of Existing Facilities
This basin is generally a natural drainage basin centered around the East Branch of the
Cocohatchee River. The natural stream bed configuration is so ill-defined that no portions of it
are included in the County’s secondary channel inventory. The flow of surface water is
northward. Due to the small size and location of the drainage area, the system is classified as a
secondary system. One water level control structure has been constructed in this stream bed to
keep the groundwater level sufficiently high and to prevent the tidal inflow of salt water.

      Existing Condition/Capacity of Facilities
The condition of this drainage system is adequate to meet the drainage needs of this basin and
therefore no major work is proposed for improvements. The operation and routine maintenance



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       Collier County Hazard Mitigation Plan                                             April 15, 2005



of the water level control structure within this drainage system is performed by the Collier
County Road Maintenance Department.

     Proposed Improvements
There are no plans for any major improvements within this basin.

C6.   AIRPORT ROAD CANAL NORTH BASIN

      Description of Basin
The Airport Road Canal North Basin is located adjacent to the East Branch Cocohatchee River
Basin and provides a drainage outlet for the surrounding lands into the Cocohatchee River Main
Canal to the north. This sub-basin is bound on the north by the Cocohatchee River Canal
Basin, on the west by the East Branch Cocohatchee Basin, on the south by the Airport Road
Canal South Basin, and on the east by the I-75 Canal Basin. The total area of the basin is
approximately 3 square miles. Some residential and commercial developments including Four
Seasons and Sam’s Club plus the Green Tree Shopping Center, Crescent Lakes and portions
of the Pelican Marsh PUD’s have been constructed in this basin.

      Historical Background
The major stormwater management facility within this basin is the canal along the east side of
Airport-Pulling Road (CR-31). This canal was dug years ago as a linear borrow pit to provide fill
material for the construction of the original road and drain the land east of the road. The basin
boundaries were established through agricultural and other construction operations. Within the
past 15 years, much of the area has developed from agricultural operations into residential or
commercial developments.

      Description of Existing Facilities
This drainage basin encompasses approximately 3 square miles. As previously stated, the
main drainage feature of this basin is the existing canal along the east side of Airport-Pulling
Road (CR-31). This canal is excavated along the entire length of Airport-Pulling Road, but a
drainage divide located at the intersection of Vanderbilt Beach Road causes the water to drain
both northward and southward from this divide and thus creates the two basins for the one
canal. There are approximately 2.0 miles of primary canal and 1 primary water level control
structure. The basin also contains approximately 5 miles of secondary canal and 1 secondary
control structure plus a secondary pump station (Victoria Park). The primary water level control
structure functions in conjunction with an existing water level control structure in the Airport
Road Canal (S.) to maintain an increased water level across the area of the natural drainage
divide, particularly during periods of low rainfall.

      Existing Condition/Capacity of Facilities
The Airport Road Canal (N.) is in good condition to handle the storm runoff from this drainage
basin. The canal was renovated during the 4-lane upgrade construction of the Airport-Pulling
Road. There are several private road crossings along this canal that could restrict the flow of
water in the event of a major rainfall event, but these are being improved as the various new
proposed development projects are constructed. The operation and maintenance of the primary
canal and structures is performed by the Big Cypress Basin. Operation and maintenance of the
secondary canals and structure is performed by the Collier County Road Maintenance
Department. Operation and maintenance primarily consists of routine maintenance on the
structures and the control and removal of aquatic vegetation when this becomes excessive and
hinders the flow of stormwater through the system. Some sediment removal work is also done



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       Collier County Hazard Mitigation Plan                                            April 15, 2005



to return the channel to its approximate original cross section when excess sediment
accumulations become a problem.

      Proposed Improvements
No new improvements are proposed for the Airport Road Canal (N.) due to the renovation as
described above.

C7.   951 CANAL NORTH

       Description of Basin
The 951 Canal North Basin is a small rural drainage basin located in the southeast quadrant of
the intersection of Immokalee Road (CR-846) and CR-951. It encompasses an area of
approximately 2 square miles of urban fringe land use. Historic usage was predominantly rural
residential with some commercial nurseries, but urban redevelopment is rapidly filling the entire
basin. This basin is bound on the north by the Cocohatchee River Canal Basin, on the west by
the Harvey Canal Basin, and on the south by the 951 Canal Central Basin, and on the east by
the Cypress Canal Basin.

      Historical Background
The 951 Canal North Basin was established as a separate basin by the construction of CR-951
and CR-846. The initial construction of CR-846 severed the area’s historical sheet flow of
surface water from the northeast and created a wetland pocket surrounded by slightly elevated
uplands. The construction of CR-951 and it’s adjacent borrow canal provided a drainage outfall
connection back to the north into the Cocohatchee River Main Canal

        Description of Existing Facilities
The only stormwater management facility within the 951 Canal North Basin is the primary canal
along the eastern side of CR-951, of which approximately 2 miles are within this basin. At the
southern end of the 951 Canal North Basin a water level control structure established the basin
boundary divide at Vanderbilt Beach Road Extension. This water level control structure was
removed a number of years ago during construction of a temporary road crossing of the canal.
It is proposed for reconstruction, so the basin delineation is maintained although under current
conditions there is no physical separation between this basin and the 951 Canal Central Basin.
The primary canal was very shallow and provided a connection between the Cocohatchee River
Main Canal and the Golden Gate Main Canal. There were numerous private culverted
driveways crossing this canal that were undersized and created additional flow restrictions.
Under normal flow conditions, this canal had a divide in the vicinity of Vanderbilt Beach Road
Extension and surface water in this basin flowed northward. However, during the summer when
surface water elevations north of CR-846 are high, this canal reversed flow direction and
discharged into the Golden Gate Main Canal to the south.

In 2002 the Big Cypress Basin initiated a total reconstruction of the primary canal, including a
reduction in the number of private crossings and their replacement with bridges. This work was
completed in early 2004 and the capacity of the canal substantially increased to provide an
adequate level of flood protection. Additionally, the canal no longer flows northward, but always
flows southward into the 951 Canal Central Basin. The reconstruction of the water level control
structure at the Vanderbilt Beach Road Extension road crossing is scheduled for 2005 as a part
of the 6-laning of the road.

      Existing Condition/Capacity of Facilities



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       Collier County Hazard Mitigation Plan                                            April 15, 2005



With the recent reconstruction of the primary canal by the Big Cypress Basin, the canal provides
sufficient capacity for the 25-year/3-day design storm. The Big Cypress Basin is responsible for
the operation and maintenance of this canal. O & M consists primarily of the control and
removal of aquatic vegetation when this becomes excessive and hinders the flow of stormwater
through the system. Some sediment removal work will also be done to return the channel to its
approximate design cross section when excess sediment accumulations become a problem.

      Proposed Improvements
With the completion of the canal reconstruction and driveway crossings by the Big Cypress
Basin, there are no planned additional improvements. Any future planned improvements would
be included in the Big Cypress Basin’s 5-Year Plan.

D.    GORDON RIVER EXTENSION BASIN

      Description of Basin
The Gordon River Extension Basin is an approximately 8.4 square mile drainage basin
immediately east of the City of Naples. This basin encompasses the northern Gordon River
drainage area and has been altered in size by the construction of roads and development sites.
The area has a multitude of land uses within its boundaries including wetlands, recreation (golf
courses), residential, and commercial. Included within this basin are The Commons, River
Reach, Wilderness, Moorings Park, Moorings Park Estates, Forest Lakes Homes and part of the
Grey Oaks PUD's, the J. & C. (Pine Ridge) Industrial Park, the Poinciana Village subdivision,
and the Wilderness, Hole in the Wall, Royal Poinciana, and the Country Club of Naples golf
courses.

       Historical Background
The Gordon River has had an important part in the development of the City of Naples. The land
near the mouth of the Gordon River Extension consists of mangrove estuarine systems that
have helped to limit the extent of development in these areas. The upstream historical drainage
basin extended much farther to the east, but the construction of roads (principally Airport Road)
with the accompanying roadside canals created separate drainage basins that reduced the
runoff to the Gordon River Extension system.

      Description of Existing Facilities
The existing drainage facilities within the Gordon River Extension Basin have been built by a
varied group of developments. As a result, the overall drainage network is difficult to describe
and is not efficient in the removal of stormwater. There are approximately 18 miles of
secondary canals within this drainage basin. There is 1 secondary water level control structure
which functions as a salinity control structure located downstream of Golden Gate Parkway near
the mouth of the basin. Additionally, there are 5 water level control structures associated with
the drainage ditch along the west side of Goodlette-Frank Road.

One of the drainage feature considerations that must be addressed is the stormwater runoff
discharged from the City of Naples that is located along the western side of this basin. A
roadside ditch along the west side of CR-851 (Goodlette-Frank Road) receives drainage from
both Collier County and the City of Naples jurisdictional areas. Beginning at the north end of the
basin at the intersection of Goodlette-Frank Road and Carica Road and flowing southward, the
County contributes all of the inflow until the ditch enters the City limits at Creech Road. From
Creech Road southward to a weir structure (GRE-01-S0150) located approximately 2300' south
of Creech Road, the ditch collects runoff from CR-851 to the east and the various City drainage
basins between CR-851 and US-41 to the west. GRE-01-S0150 then directs the normal flow


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       Collier County Hazard Mitigation Plan                                           April 15, 2005



into a cross drain (GRE-03-S0100) which outlets to the east into a ditch (County jurisdiction)
leading to the Gordon River. This weir structure also raises the water levels in the Goodlette-
Frank Road ditch to allow additional discharge through the cross drains north of Creech Road
and thus reduce the amount of flow through the cross drain at GRE-01-S0150. During periods
of excessive flow, a bleeder notch in this weir allows some runoff to continue flowing southward
along CR-851.

From GRE-01-S0150 southward to a point approximately 800' south of Fleischmann Blvd. the
ditch continues collecting runoff from CR-851 to the east and the various City drainage basins
between CR-851 and US-41 to the west. At this point there is another cross drain (GRE-02-
S0100) which outlets to the east into the Gordon River watershed. The drainage in the roadside
ditch can either outlet through this cross drain into County jurisdiction or continue flowing
southward until it outlets through a series of pipes and ditches into the Gordon River in City
jurisdiction approximately 400' south of 7th Ave. N. No additional drainage is contributed to the
ditch from CR-851 but it must be noted that some of the roadside storm sewer does outlet into
some of the ditch cross drains. The drainage areas outletting into the cross drains are from
approximately 1350' north of 7th Ave. N. to 1100' south of 7th Ave. N. and from 1st. Ave. S. to
US-41 which is the endpoint for CR-851.

      Existing Condition/Capacity of Facilities
As mentioned previously, the condition of most of the drainage facilities within this basin
produces an inefficient stormwater removal system. Since almost all of these facilities have
been built by various private interests through a number of years of development, there is no
uniformity to their design. The maintenance of the canals is essentially the responsibility of
these private owners and past efforts to obtain County maintenance agreements have met with
poor response. As a result, the existing canals are inadequate in size and choked with
vegetation in many places and are generally insufficient to pass the design storm runoffs.

An analysis of the roadside ditch along CR-851 (Goodlette-Frank Road) provided the following
information. The outfall from GRE-01-S0150 receives approximately 33 cfs from the City
drainage areas. The outfall from GRE-02-S0100 located approximately 800' south of
Fleischmann Blvd. receives approximately 63 cfs from the City drainage areas. The outfall from
the City's cross drain located approximately 400' south of 7th Ave. N. receives approximately 16
cfs from the County drainage areas. The outfall from the City's cross drain located at the
intersection of CR-851 and US-41 receives approximately 9 cfs from the County drainage area.

       Discussion of Previous Studies
Several studies have been performed to analyze the drainage problems and propose solutions
for this basin. One study, "Master Plan, Water Management District No. 7, Including the
Cocohatchee and Gordon River Basins, Collier County, Florida" by Black, Crow and Eidsness,
Inc. in March, 1975, presents a detailed engineering study of the drainage needs for this basin.
This report incorporates a series of excavated channels and water level control structures to
effectively remove excess stormwater during periods of wet weather yet maintain a high
groundwater elevation throughout the year to help replenish the Coastal Ridge aquifer that is a
vital source of potable water for the City of Naples. A more recent study, "Gordon River
Watershed Study" by CH2M Hill in February, 1980, considered these same problems and
solutions but evaluated them more from an economic standpoint.

Several studies have also been completed which considered the environmental impacts of any
modification to the Gordon River watershed. "An Environmental Evaluation of the Gordon River
of Naples, Florida and the Impact of Developmental Plans" by Howard T. Odum, Charles


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       Collier County Hazard Mitigation Plan                                            April 15, 2005



Littlejohn, and Wayne C. Huber in September, 1972, evaluated the work performed by a natural
system and made suggestions for maintaining and/or restoring the area to its natural state and
limiting the types of development to be allowed in the future. Two studies, "Hydrological Effects
of the Proposed Gordon River Canal, Naples, Florida" by Bertan W. Morrow and John A.
Stevens in October, 1971, and "Hydrological Study of the Effects of the Proposed Gordon River
Canal, Naples, Florida" by Black, Crow and Eidsness, Inc. in 1971, discussed the effects that
the construction of the Gordon River Extension canal system would have on the Coastal Ridge
aquifer which is a primary potable water source for the City of Naples.

       Proposed Improvements
A recently completed multi-year joint planning effort by the County, the City of Naples, and the
Big Cypress Basin identified the existing stormwater facilities within the basin and developed a
set of alternatives analyses to determine what stormwater management improvements are
needed within the Gordon River Extension Basin. Initial design and permitting is currently
budgeted in Fiscal Year 2004/05 for three of the twenty-two identified improvements. In 2003
the County acquired a vacant parcel of land of approximately 50 acres in size near the southern
(downstream) end of the Gordon River Extension Basin. This land will be utilized to construct a
stormwater detention facility that will benefit the entire basin and provide improved stormwater
quality and quantity discharges into Naples Bay. Upon completion of the construction of the
identified improvements, the Gordon River Extension Basin is anticipated to have better flood
protection and improved water quality discharge.

E. HENDERSON CREEK BASIN

      Description of Basin
The Henderson Creek Basin is a medium sized drainage area of approximately 49 square
miles. It is located in the south central portion of Collier County and is bound by CR-951 to the
west, the Rookery Bay estuary to the southwest, the US-41 Outfall Swale No. 1 and US-41
Outfall Swale No. 2 Basins to the south, the Seminole Park Outlet Basin to the southeast, the
Faka Union Canal System Basin to the east, and the Main Golden Gate System to the north.
There is very extensive development along the western edge of the basin adjacent to CR-951
and along the US-41 border The existing rock pits near the US-41 and CR-951 intersection are
currently being used as a potable water supply source for the City of Marco Island.

      Historical Background
The majority of the Henderson Creek Basin is identified as wetlands. This land is extremely flat
and any surface runoff is naturally directed toward the southwest where it enters the Rookery
Bay estuary via Henderson Creek. The boundaries of this basin were established by the
excavation of the Main Golden Gate Canal and the Faka Union Canal Systems and the CR-951
borrow canal, but little or no drainage systems have been created within the interior portions of
the basin.

       Description of Existing Facilities
There are 4 major constructed drainage facilities within this basin. They consist of
approximately 7 miles of primary canal, 4 miles of secondary canal, 1 primary water level control
structure, and 1 secondary water level control structure. The northern most facility is the I-75
(Alligator Alley) borrow canal. It is considered a secondary canal and directs some flow
westward to the CR-951 borrow canal while also allowing additional flow to pass beneath I-75
and continue in a southwesterly direction toward Henderson Creek. The CR-951 borrow canal,
which forms the western boundary, is considered a primary canal and collects water from the
basin and directs it southward into Henderson Creek. The one primary water level control


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structure (HEC-00-S0120) is located in this canal immediately upstream of the US-41 crossing.
The remaining facilities are secondary and consist of the US-41 borrow canal which intercepts
the flow of water and outlets either through the Henderson Creek water level control structure or
a secondary water level control structure (HEC-03-S0100) which eventually discharges into the
eastern branch of Henderson Creek.

      Existing Condition/Capacity of Facilities
The canals within the Henderson Creek Basin were constructed as road borrow canals and
have been in existence for many years. They primary canals and structures are maintained by
the Big Cypress Basin while the secondary canals and structures are maintained by the Collier
County Road Maintenance Department. The maintenance primarily consists of the control and
removal of aquatic vegetation when this becomes excessive and hinders the flow of stormwater
through the system. Some sediment removal work is also done to return the canals to their
approximate original cross sections when excess sediment accumulations become a problem.
While most of the canal system is well maintained, it is generally of insufficient size to rapidly
pass the volumes of surface water that enter the system during periods of excessive rainfall.
The two existing water level control structures are relatively new, in excellent condition, and,
although very controversial, are capable of passing the design storm flows of an improved canal
system.

       Discussion of Previous Studies
The Collier County Stormwater Management Department files contain a report, "Belle
Meade-Royal Palm Hammock Water Management Plan", prepared by CH2M Hill in July, 1982.
This report discusses the possible development of, and the environmental effects upon, the
wetland wilderness within this basin. A detailed water management plan was developed which
emphasized the need to preserve large portions of this wetland and adapt the method of
development to conform to the wetland environment. This plan has not been implemented and
very little additional development, other than along the 1-mile wide strip of urban fringe
designated land along the CR-951 Canal frontage, has occurred within this basin since the
report was written.

In 1990 Johnson Engineering, Inc. prepared a water management plan for the Henderson Creek
basin as a part of the design efforts to 4-lane CR-951. The report, "Watershed Analysis
Henderson Creek Basin", identified a need to modify the existing channel capacity by enlarging
the cross section, reconstructing many of the culverted road crossings, possibly constructing an
additional weir, and modifying the existing weir adjacent to US-41. When the road was 4-laned,
the canal was not extensively modified due to environmental permitting and right-of-way
constraints.

      Proposed Improvements
The Big Cypress Basin, with directional assistance from the County, has initiated a basin master
planning study for an area known as the Belle Meade Watershed that includes the Henderson
Creek, US-41 Outfall Swale No. 1, US-41 Outfall Swale No. 2, and Seminole Park Outlet basins.
This Belle Meade Watershed Master Plan may identify improvements for water quantity, water
quality, and environmental enhancement. However, the study was initiated in 2004 and
recommendations are not anticipated until late 2005 or early 2006. There are no proposed
improvements to the stormwater management systems of this basin at this time.




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F.    FAKA-UNION SYSTEM

The Faka-Union System is a large drainage area in central Collier County. This Basin was
created by the excavation of the Golden Gate Estates canal network in the 1960's and is
separated from the Main Golden Gate Canal Basin during normal flow situations by a water
level control structure. The total area served by this stormwater system is approximately 151
square miles and can be divided into four identifiable basins. They are as follows:

      F1.      Faka-Union Canal Basin
      F2.      Miller Canal Basin
      F3.      Merritt Canal Basin
      F4.      Prairie Canal Basin

The land use map identifies the principal land use in the Faka-Union System as residential
estates land use. An extensive roadway and canal system was installed throughout the basin
during initial construction and the land sold to private citizens with lot sizes typically ranging
from 1.25 to 5.00 acres. The northern half (north of I-75) of this basin is being developed by
numerous individual homeowners while the southern half (south of I-75) of this basin has almost
no residential development, and the State of Florida is completing acquisition of all the
properties as part of a program for the hydrologic restoration of the so-called “Southern Blocks”.

       Previous Studies
Numerous studies have been prepared to address the water management problems associated
with the Golden Gate Estates canal network. As has been previously mentioned, this network
consists of the Main Golden Gate Canal System and the Faka-Union System. The studies that
included discussions on the Main Golden Gate Canal System have been described previously in
this document.

The "Proposed Interim Modifications, Golden Gate Estates Canal System" report prepared by
CH2M Hill in November 1978, addressed the problem of excessive fresh water discharge into
the Naples Bay and Faka-Union Bay estuaries. This report recommended the permanent
physical separation of the two basins by the installation of two earth plugs in the canals which
connect the two systems. Installation of the two plugs would prevent runoff from the Faka-
Union System from flowing into the Golden Gate system and would result in a significant
decrease in outflow to Naples Bay. It also recommended that a flashboard system be
constructed on five weirs in the Faka-Union System, thus making it possible to raise the weir
crests an average of two feet. This would result in decreasing the runoff rate, raising surface
and groundwater levels and providing for additional storage of water during the dry season.

The U.S. Army Corps of Engineers prepared the “Golden Gate Estates, Reconnaissance
Report” in April 1980. The report addressed the environmental harm that the Faka-Union
System was doing to the surrounding land and estuary. The report recommended that the canal
system be modified to reduce the amount of fresh water being discharged into Faka-Union Bay
and restore the hydroperiod of the wetlands that existed prior to the construction of the canal
system. Since this was an overview type of report, it recommended that a more detailed study
be undertaken to develop definite solutions to the water management problems, but it did
recommend a plan called Alternative D. This plan recommended the construction and/or
modification of a number of weirs, water level control structures, and earth plugs to raise the
groundwater elevations and the construction of several water discharge spreaders to partially
restore the natural sheetflow of surface water to the Fakahatchee Strand area to the east and
the Faka-Union Bay to the south.


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The U.S. Army Corps of Engineers prepared a second report, “Golden Gate Estates, Draft
Feasibility Report”, in February 1986. This report also considered the feasibility of modifying the
existing water control system within the Faka-Union basin. It recommended that the plan known
as Alternative C be implemented. Alternative C is very similar to the previously described
Alternative D, but it does not incorporate the spreaders.

A report, "The Effect of the Faka Union Canal System on Water Levels in the Fakahatchee
Strand, Collier County, Florida" was prepared by the U.S.G.S. and recorded as Water
Resources Investigations 77-61 in September 1977. This study discussed the effects that the
Faka Union Canal System, principally the Merritt (aka "E") and Prairie (aka "F") Canals, had on
the removal of traditional surface water sheet flow from the western edge of the Fakahatchee
Strand. The water levels south of the weir at Janes Scenic Drive and Stewart Boulevard were
shown to slope from the Strand to the canal throughout the year. However, throughout the
winter and spring when the structure was closed, the gradient was flat and groundwater flow
toward the canal upstream of the weir was minimal. At the beginning of the rainy season, in
June, water levels rose in the canal north of the structure, and water flowed from the canal into
the aquifer and around the control structure.

F1.   FAKA-UNION CANAL BASIN

      Description of Basin
The Faka-Union Canal Basin is located immediately east of the Miller Canal Basin, extends
from CR-846 to US-41, and contains approximately 57 square miles of "estates" land use with
some mining and agricultural parcels also located in the northern portion. The basin is bound
by the Cocohatchee River Basin to the north, the Main Golden Gate Canal and Miller Canal
Basins to the west, the Faka Union Bay estuary to the south, and the Merritt Canal Basin to the
east. The Faka-Union Canal is the main canal of the Faka Union System.

      Historical Background
The excavation of the Faka-Union Canal created this basin. Prior to any construction, the land
was part of a wetland system between the Henderson Creek drainage area and the
Fakahatchee Strand area. The first major construction project within this basin was SR-84 (also
known as Alligator Alley which has now been reconstructed as I-75). Cross drains were
periodically installed so that there was only a minimal effect to the wetland system. Following
construction of the Faka-Union Canal, the groundwater level was lowered and the surface runoff
was intercepted by the canal instead of continuing as sheetflow toward the southwest.

      Description of Existing Facilities
There are approximately 29 miles of primary canal and 7 weirs in this sub-basin. This canal
directs the flow of water southward through the center of the Golden Gate Estates area and into
the Faka-Union Bay estuary. In addition to the 7 weirs, there are several box culverts or bridges
at the various road crossings. This canal also intercepts some discharge from the I-75 borrow
canal. There are two side secondary canals that discharge into the Faka-Union Canal. Their
combined length is approximately 2 miles.

     Existing Condition/Capacity of Facilities
The Faka-Union Canal was constructed many years ago. The Big Cypress Basin performs the
operation and maintenance of the primary canal and associated water level control structures.
The Collier County Road Maintenance Department is responsible for the maintenance of the
secondary canals. Operation and maintenance primarily consists of the control and removal of


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aquatic vegetation when this becomes excessive and hinders the flow of stormwater through the
system. Some sediment removal work is also done to return the canal to its approximate
original cross section when excess sediment accumulations become a problem. This canal,
when properly maintained, is generally of sufficient size to adequately pass the design storm
flows and provide a reasonable degree of flood protection. In 1983 the County modified 3 of the
water level control structures (weirs) by adding wooden flashboard facilities to reduce the
observed overdrainage of the area. From 1991 to 1994 the Big Cypress Basin updated these
modifications by converting the wooden flashboards to steel gates.

      Proposed Improvements
The Faka-Union Canal, north of I-75, is of sufficient size and condition so that no improvements
are presently planned for channel modification to increase capacity. The Big Cypress Basin has
developed a long-range plan for the hydrologic restoration of the entire Faka-Union System
south of I-75. State funding was utilized to purchase the land area south of I-75, and only two
private landowners remain. The restoration plan is undergoing final federal agency review for
approvals. It involves the construction of a large stormwater pumping station in the Faka Union
canal approximately two miles south of I-75, the installation of numerous earth plugs in the Faka
Union canal downstream of the pumping station, and the removal of many miles of existing dirt
roads to restore sheetflow through the southern half of the basin. Future planning and
improvements will involve funding from the Big Cypress Basin and coordination with the County
and State.

F2.   MILLER CANAL BASIN

      Description of Basin
The Miller Canal Basin is the westernmost basin within the Faka-Union System. It contains
approximately 30 square miles of mostly uninhabited Golden Gate Estates land and is bound by
the Main Golden Gate Canal Basin to the north and northwest, the Henderson Creek and
Seminole Park Outlet Basins to the west, and the Faka-Union Canal Basin to the south and
east.

      Historical Background
The excavation of the Miller Canal of the Faka-Union System created this basin. Prior to any
construction, the land was part of a wetland system between the Henderson Creek drainage
area and the Fakahatchee Strand area. The first major construction project within this basin
was SR-84 (also known as Alligator Alley which has now been reconstructed as I-75). Cross
drains were periodically installed so that there was only a minimal effect to the wetland system.
Following construction of the Miller Canal, the groundwater level was lowered and the surface
runoff was intercepted by the canal instead of continuing as sheetflow toward the southwest.

       Description of Existing Facilities
There are approximately 18 miles of primary canal and 2 miles of secondary canal within this
basin. The major drainage facility within the basin is the Miller Canal. It is the westernmost
canal in the Faka Union System and has its northern beginning at structure MJC-00-S0160 (aka
Miller 3) that separates the Miller Canal from the Main Golden Gate Main Canal. This weir is
designed to direct all normal flow through the Main Golden Gate Main Canal but allow for an
overflow to discharge into the Faka-Union System via the Miller Canal during periods of high
runoff. The Miller Canal directs surface discharge south over two existing weirs until it merges
with the other Faka-Union System canals and discharges into the Faka-Union Bay estuary.
This canal also receives some discharge from the I-75 borrow canal at the I-75 crossing.



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There are three weirs in the Miller Canal. The previously mentioned MJC-00-S0160 is at the
northern beginning, MJC-00-S0130 (aka Miller 2) is located just south of the I-75 crossing, and
MJC-00-S0120 (aka Miller 1) is located near the Stewart Blvd. crossing.

      Existing Condition/Capacity of Facilities
The Miller Canal was constructed in the 1960’s. The Big Cypress Basin performs the operation
and maintenance of the primary canal and associated water level control structures.
Maintenance of the secondary canal was performed by the Collier County Road Maintenance
Department. Operation and maintenance primarily consists of the control and removal of
aquatic vegetation when this becomes excessive and hinders the flow of stormwater through the
system. Some sediment removal work is also done to return the canal to its approximate
original cross section when excess sediment accumulations become a problem. This canal,
when properly maintained, is generally of sufficient size to adequately pass the design storm
flows and provide a reasonable degree of flood protection. In 1983 the County modified two of
the water level control structures (weirs) by adding wooden flashboard facilities to reduce the
observed overdrainage of the area. In 1994 the Big Cypress Basin updated one of these
modifications by converting the wooden flashboards to steel gates.

       Proposed Improvements
The Miller Canal, north of I-75, is generally of sufficient size and condition, and no
improvements are presently planned for channel modification to increase capacity. As
previously discussed for the Faka Union Canal Basin, the Big Cypress Basin has developed a
long-range plan for the hydrologic restoration of the entire Faka-Union System south of I-75.
State funding was utilized to purchase the land area south of I-75. The restoration plan is
undergoing final federal agency review for approvals. It involves the construction of a large
stormwater pumping station in the Miller canal approximately two miles south of I-75, the
installation of numerous earth plugs in the Miller canal downstream of the pumping station,
abandonment of the secondary canals south of I-75, and the removal of many miles of existing
dirt roads to restore sheetflow through the southern half of the basin. Future planning and
improvements will involve funding from the Big Cypress Basin and coordination with the County
and State.

F3.   MERRITT CANAL BASIN

       Description of Basin
The Merritt Canal Basin is located just east of the Faka-Union Canal Basin. It contains
approximately 47 square miles of agricultural, "estates", and wetland land use. Most of the land
is uninhabited due to the extensive agricultural operations and wetlands north of I-75 and the
lack of available facilities south of I-75. This basin is bounded by the Faka-Union Canal Basin
to the west, the Faka Union Bay estuary to the south, and the Fakahatchee Strand Basin to the
north and east.

       Historical Background
This basin was created during the construction of the Merritt Canal in the late 1960's in an
attempt to drain the surface water from the Picayune Strand south of I-75. Due to the natural
drainage features of the Picayune Strand and its connection to the Stumpy Strand to the north
of I-75, the drainage area is much larger than the relatively small amount of drainage canals
would seem to indicate.

      Description of Existing Facilities



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There are approximately 12 miles of primary canal and 2 primary water level control structures
within this basin. There are approximately 3 miles of secondary canal. All of these facilities are
located in the southern section of the basin, beginning approximately one mile north of I-75.
The water level control structure (EMC-00-S0120) is located a short distance north of Stewart
Boulevard. The Lucky Lake water level control structure (EMC-00-S0135), located
approximately 0.75 miles south of I-75, was constructed and is maintained by the Big Cypress
Basin. The Merritt Canal discharges into the Faka-Union Canal

       Existing Condition/Capacity of Facilities
The Merritt Canal is generally of sufficient capacity to meet the needs of the basin. There is a
published opinion that the capacity of the canal needs to be greatly reduced to minimize the
dewatering potential to the adjacent Fakahatchee Strand Preserve area. The Big Cypress
Basin is currently responsible for the operation and maintenance of the primary facilities within
this basin. Maintenance of the secondary canal is performed by the Collier County Road
Maintenance Department. Maintenance involves the control of aquatic vegetation and removal
of excess sediment deposits in the canal. The water level control structure used to be an
automatic mechanical gate. However this was removed many years ago and replaced with
flashboards because of excessive vandalism. The Big Cypress Basin places and/or removes
the flashboards as seasonal conditions require.

       Proposed Improvements
The Merritt Canal is generally of sufficient size and condition, and no improvements are
presently planned for channel modification to increase capacity. As previously discussed for the
Faka Union Canal Basin, the Big Cypress Basin has developed a long-range plan for the
hydrologic restoration of the entire Faka-Union System south of I-75. State funding was utilized
to purchase the land area south of I-75. The restoration plan is undergoing final federal agency
review for approvals. It involves the construction of a large stormwater pumping station in the
Merritt canal approximately one mile south of I-75, the installation of numerous earth plugs in
the Merritt canal downstream of the pumping station, and the removal of many miles of existing
dirt roads to restore sheetflow through the southern half of the basin. The Big Cypress Basin
has constructed also designing an additional water level control structure to be placed in the
upper end of the Merritt Canal to further reduce the current over drainage of lands upstream of
I-75. The exact location and final design are not yet determined. Future planning and
improvements will involve funding from the Big Cypress Basin and coordination with the County
and State.

F4.   PRAIRIE CANAL BASIN

      Description of Basin
The Prairie Canal Basin is the eastern most basin within the Faka-Union System. It contains
approximately 17 square miles of "estates", and wetland land use. Most of the land is
uninhabited due to the extensive wetlands and the lack of available facilities. This basin is
bounded by the Merritt Canal Basin to the north and west and the Fakahatchee Strand Basin to
the east and south.

       Historical Background
The Prairie Canal Basin was created during the construction of the Prairie Canal in the late
1960's in an attempt to drain the surface water from the Picayune Strand south of I-75. The
Prairie Canal was also supposed to provide a drainage outlet for the proposed community of
Golden Gate Gardens.



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       Description of Existing Facilities
There are approximately 10 miles of primary canal and 1 primary water level control structure
within this basin. There are approximately 4 miles of secondary canals. The water level control
structure is located in just north of Janes Scenic Drive where it connects to Stewart Blvd.. The
Prairie Canal discharges into the Merritt Canal that in turn discharges into the Faka-Union
Canal. None of the proposed drainage facilities for Golden Gate Gardens were ever
constructed.

       Existing Condition/Capacity of Facilities
The Prairie Canal is generally of sufficient capacity to meet the needs of the basin. There is a
published opinion that the capacity of the canal needs to be greatly reduced to minimize the
dewatering potential to the adjacent Fakahatchee Strand Preserve area. The Big Cypress
Basin is currently responsible for the operation and maintenance of the primary facilities within
this basin. Maintenance of the secondary canal is performed by the Collier County Road
Maintenance Department. Maintenance involves the control of aquatic vegetation and removal
of excess sediment deposits in the canal. The water level control structure used to be an
automatic mechanical gate. However this was removed many years ago and replaced with
flashboards because of excessive vandalism. The Big Cypress Basin places and/or removes
the flashboards as seasonal conditions require.

       Proposed Improvements
The Prairie Canal is generally of sufficient size and condition, and no improvements are
presently planned for channel modification to increase capacity. The Big Cypress Basin is
developing a long-range plan for the entire Faka-Union System south of I-75 and State funding
is being utilized to purchase the land area. Future planning and improvements will involve
funding from the Big Cypress Basin and coordination with the County and State.

G.    SOUTHERN COASTAL BASIN

The Southern Coastal Basin is a mostly undeveloped drainage area in the southern portion of
Collier County. The area consists of three separate drainage basins that account for surface
water near US-41 and between the southern portions of the Henderson Creek Basin and the
Faka-Union System. The three separate drainage basins are as follows:

      G1.      US-41 Outfall Swale No. 1
      G2.      US-41 Outfall Swale No. 2
      G3.      Seminole Park Outlet
      G4       Tamiami Trail Canal

      Previous Studies
Although the files of the Collier County Stormwater Management Department contain
engineering studies of the adjacent major drainage basins, there are no studies specifically
covering this area. Portions of the area were included in the “Belle Meade-Royal Palm
Hammock Water Management Plan” prepared by CH2M Hill in July, 1982.

G1.   US-41 OUTFALL SWALE NO. 1

      Description of Basin
The US-41 Outfall Swale No. 1 Basin is a small drainage area in the southwestern part of Collier
County. This basin is approximately 5 square miles in area and consists almost entirely of
agricultural operations. The West Wind Mobile Home and the Imperial Wilderness RV parks are


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       Collier County Hazard Mitigation Plan                                              April 15, 2005



located within the basin boundaries. A listing of the PUD's and their status can be found in
Appendix II of this Section. The basin is bound by the Henderson Creek Basin to the north and
west, US-41 and the Addison Bay estuary to the south, and the US-41 Outfall Swale No. 2
Basin to the east.

      Historical Background
The basin boundaries were created by the construction of dikes around the agricultural
operations in the area. The basin consists of very flat and low lying land that is subject to
frequent flooding from moderate to severe storms.

      Description of Existing Facilities
The major existing drainage facility within the US-41 Outfall Swale No. 1 is the borrow canal
along the north side of US-41. This borrow canal is considered as a secondary canal and is
approximately 2 miles long. Several cross drains allow for the borrow canal to discharge
stormwater beneath US-41. However, the existence of dikes around the agricultural operations
to the south of US-41 greatly hinders the southward flow of this stormwater. Old agricultural
ditches currently allow for the stormwater to slowly drain southward, but these vary in size and
capacity.

      Existing Condition/Capacity of Facilities
The entire drainage canal system within this basin is insufficient to provide the flood protection
needs for the residents and businesses. The Collier County Road Maintenance Department
performs the maintenance of the US-41 borrow canal. This maintenance primarily consists of
the control and removal of aquatic vegetation when this becomes excessive and hinders the
flow of stormwater through the system. Some sediment removal work is also done to return the
canal to its approximate original cross section when excess sediment accumulations become a
problem. The agricultural outlet ditches are maintained by the agricultural operations and are in
various stages of constriction.

      Proposed Improvements
Detailed engineering plans have been prepared to construct a minimal but adequate stormwater
management system for this basin. The plans propose to reconstruct the 2 miles of US-41
borrow canal to an appropriate cross section and connect it to an existing secondary canal
associated with the West Wind area. A water level control structure is proposed for construction
where the US-41 borrow canal discharges through a cross drain facility beneath the roadway. A
collector swale is proposed for the south side of US-41 to provide an improved discharge for the
cross drains. The collector swale is proposed to discharge into a larger swale which will replace
the use of the agricultural ditches and direct the stormwater to a spreader system prior to
discharge into the estuary. The new swale construction will be approximately 2 miles in length.
An additional one mile of secondary canal is also proposed to connect the spreader system to
the easternmost US-41 discharge point from the adjacent Henderson Creek Basin. Efforts to
implement these plans have been continually delayed by the inability to obtain the necessary
drainage easements from the property owners. Recent changes in ownership may allow for the
project to continue within the next five years.

G2.   US-41 OUTFALL SWALE NO. 2

     Description
The US-41 Outfall Swale No. 2 Basin is very similar to the US-41 Outfall Swale No.1 Basin.
The basin is approximately 4 square miles is size and contains some trailer parks and individual
houses in addition to extensive agricultural operations. A listing of the PUD's and their status


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can be found in Appendix II of this Section. The dikes from the agricultural operations have
established most of the basin boundaries. This basin is bound by the Henderson Creek Basin
to the north, the US-41 Outfall Swale No. 1 Basin to the west, US-41 and the Addison
Bay/Marco River estuary to the south, and the Seminole Park Outlet Basin to the east.

      Historical Background
In similar fashion to US-41 Outfall Swale No. 1 Basin the basin boundaries were created by the
construction of dikes around the agricultural operations in the area. Likewise, the basin consists
of very flat and low lying land that is subject to frequent flooding from moderate to severe
storms.

      Description of Existing Facilities
The major existing drainage facility within the US-41 Outfall Swale No. 2 Basin is the borrow
canal along the north side of US-41 which is included in the inventory for the Seminole Park
Outlet Basin. This borrow canal, considered as a secondary canal, is approximately 1 mile long
and discharges into cross drains beneath US-41. There are also some secondary roadside
ditches which discharge stormwater from the north into the US-41 borrow canal. South of US-
41 the flow of stormwater is restricted to a small roadside ditch and an old agricultural ditch.

      Existing Condition/Capacity of Facilities
The entire drainage canal system within this basin is insufficient to provide the flood protection
needs for the residents and businesses. The Collier County Road Maintenance Department
maintains only the US-41 borrow canal. This maintenance primarily consists of the control and
removal of aquatic vegetation when this becomes excessive and hinders the flow of stormwater
through the system. Some sediment removal work is also done to return the canal to its
approximate original cross section when excess sediment accumulations become a problem.
The small roadside outlet ditch and the old agricultural ditch are insufficient in size to pass much
flow and the landowners perform their maintenance.

       Proposed Improvements
Detailed engineering plans have been prepared to construct a minimal but adequate stormwater
management system for this basin. The plans propose to reconstruct the 1 mile of US-41
borrow canal to an appropriate cross section. Where the US-41 borrow canal discharges
through cross drains beneath the roadway, a collector swale is proposed for the south side of
US-41 to provide an improved discharge for the cross drains. The collector swale is proposed
to discharge into a larger swale that will transport the stormwater around the eastern side of the
agricultural operations south of US-41 and direct the stormwater to a spreader system prior to
discharge into the estuary. There is also a small swale proposed to improve drainage from the
Auto Ranch Road area. Efforts to implement these plans have been continually delayed by the
inability to obtain the necessary drainage easements from the property owners. There are no
proposed plans to implement construction of improvements in this basin at this time.

G3.   SEMINOLE PARK OUTLET BASIN

      Description of Basin
The Seminole Park Outlet Basin is a medium size drainage area of approximately 28 square
miles. It is bound by the Henderson Creek Basin to the north and northwest, the US-41 Outfall
Swale No. 2 Basin to the west, Palm Bay estuary to the south, and the Miller Canal Basin and
Tamiami Trail Canal Basin to the east. This basin contains some of the original watershed area
of the Blackwater River that flows into Blackwater Bay.



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       Collier County Hazard Mitigation Plan                                             April 15, 2005



Most of the northern and eastern portions of this basin are undeveloped wetland. The central
portion, primarily north of US-41, is divided into large agricultural tracts. This basin also
contains the Collier Seminole State Park. The Park is located in the southern portion of the
basin and provides the drainage outlet for the entire basin.

       Historical Background
Prior to the construction of US-41 or any of the dikes around the agricultural fields, the entire
basin functioned as a wetland that discharged into the estuaries to the south. Construction
projects soon directed the overland sheet flow into specific discharge points, principally through
cross drains under US-41 into West Palm Run. The construction of the Faka-Union System
also reduced the drainage area of the lands contributing surface water to the Seminole Park
Outlet Basin.

      Description of Existing Facilities
This basin contains approximately 5 miles of secondary borrow canal along the north side of
US-41. This canal outlets under a bridge near the intersection of US-41 and SR-92 into West
Palm Run which flows through the Collier Seminole State Park and discharges into Royal Palm
Hammock Creek and then into Palm Bay. An additional crossing under US-41 discharges the
surface runoff from the eastern wetland portion of this basin into the Blackwater River.

       Existing Condition/Capacity of Facilities
The existing canal and road crossings are generally adequate to meet the drainage
requirements for the basin. The Florida Department of Transportation has the responsibility to
maintain and keep the borrow canal and cross drains functioning properly. However, to insure
that the system is adequately maintained, the Collier County Road Maintenance Department
performs the maintenance. This maintenance includes the control and removal of aquatic
vegetation when it becomes excessive and hinders the flow of stormwater through the system.

     Proposed Improvements
There are no proposed improvements to the facilities in this basin at this time.

G4.   TAMIAMI TRAIL CANAL

      Description of Basin
The Tamiami Trail Canal Basin is a small pocket of predominantly wetlands north of US-41
(Tamiami Trail) between the southwest corner of the Faka-Union System and the Seminole
Park Outlet Basin. This basin encompasses approximately 6 square miles of rural land. There
is no known development within this basin.

      Historical Background
The north and east boundaries of this basin were established in the 1960’s by the construction
of the lower portion of the Miller Canal of the Faka-Union System. The Miller Canal severed the
wetlands in this basin from their historical sheetflow from the north. During the summer periods
of heavy rainfall the Miller Canal can still overflow its banks and provide stormwater into this
basin. The basin is bounded on the south by US-41 and on the west by a filled dirt roadway
(aka Miller Blvd. Extension) used by some people as a shortcut into the southern portion of
Golden Gate Estates from US-41.

      Description of Existing Facilities




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The only drainage facilities that have been constructed in this drainage basin are the borrow
canal that was excavated to provide the roadbed fill material for US-41 and the cross drains
beneath US-41 to allow for the stormwater to pass from the north to the south.

      Existing Condition/Capacity of Facilities
The borrow canal and roadway cross drains along US-41 were designed to approximate the
original sheetflow conditions of this area. The condition of the canal and cross drains is
generally good and the capacities sufficient to prevent major backup above the roadway surface
of any surface water from the typical storm events. The maintenance of this canal is performed
by the Florida Department of Transportation and primarily consists of the control and removal of
aquatic vegetation when this becomes excessive and hinders the flow of stormwater through the
system. Some sediment removal work is also done to return the channel to its approximate
original cross section when excess sediment accumulations become a problem.

     Proposed Improvements
There are no proposed improvements for this basin.

H.    BARRON RIVER SYSTEM

The Barron River Canal System is a large watershed area located in the central part of Collier
County. The western boundary of this area is approximately one half mile west and parallel to
State Route 29 (SR-29). This area consists primarily of wetlands and agricultural land and, for
purposes of analysis, is divided into the following four basins:

      H1.      Okaloacoochee Slough Basin
      H2.      Barron River Canal North Basin
      H3.      Urban Immokalee Basin
      H4.      Barron River Canal Basin

       Previous Studies
The only study within the files of the Collier County Stormwater Management Department that
has been completed for this portion of the County is titled "Final Report on the Augmentation of
Surficial Flow Through the Fakahatchee Strand, Collier County, Florida". William J. McElroy
with the Florida Department of Environmental Regulation, and Captain K. C. Alvarez with the
Florida Department of Natural Resources prepared it in September 1975. This report proposed
to construct a dike across the Main Barron River Canal approximately 3.5 miles north of SR-84.
The dike would divert the normal flow level of water under an existing bridge on SR-29 and into
the Fakahatchee Strand through the use of a spreader waterway. The dike would be
constructed so that it would allow excess water to be passed into the Main Barron River Canal
during storm events. The diversion of this water into the Strand would help restore the water
that had historically entered the system from the Barron River (N.) Canal and Okaloacoochee
Slough Basins prior to any construction.

H1.   OKALOACOOCHEE SLOUGH BASIN

       Description of Basin
The Okaloacoochee Slough Basin is a large drainage area located in north central Collier
County. The Okaloacoochee Slough is a natural drainage feature and functions, in conjunction
with the Main Barron River Canal Basin, as a major drainage divide to separate Hendry County
and eastern Collier County from western Collier County. This basin contains approximately 121
square miles of wetlands and agricultural land use with some isolated rock mining activities.


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       Collier County Hazard Mitigation Plan                                             April 15, 2005




The Okaloacoochee Slough Basin is bound by the Corkscrew Slough Basin and the Barron
River Canal North Basin to the west, the Fakahatchee Strand Basin to the southwest, the
Barron River Canal Basin to the south, and Hendry County to the east and north. This basin
contains approximately 20 square miles of Hendry County within its drainage area. Its
proportional capacity of the system is still unknown following the completion of the Collier
County Stormwater Management Master Plan.

      Historical Background
The boundaries of the Okaloacoochee Slough Basin are very vague due to the extensive
wetlands in the region and the numerous agricultural operations that have constructed dikes
and ditches for many years. The size of the slough and the amount of stormwater it contains
have limited the ability to utilize the land for anything but a water reservoir.

        Description of Existing Facilities
The Okaloacoochee Slough is a large natural drainage feature and very few man-made facilities
have been built within this basin. Approximately 9 miles of secondary canal have been
excavated in conjunction with the construction of County Line Road (CR-858). There are no
water level control structures, but there are several multiple pipe road crossings along this canal
prior to its discharging into the Slough. The agricultural Interceptor Canal is a poorly maintained
facility that discharges water from Hendry County into the Okaloacoochee Slough.

      Existing Condition/Capacity of Facilities
The County Line Road Canal has been in existence for many years. The maintenance of this
canal is performed by the Collier County Road Maintenance Department and primarily consists
of the control and removal of aquatic vegetation when this becomes excessive and hinders the
flow of stormwater through the system. Some sediment removal work is also done to return the
channel to its approximate original cross section when excess sediment accumulations become
a problem. The canal is of generally sufficient size to provide the desired level of service for
flood protection.

        Proposed Improvements
There are no major modifications or improvements proposed within this basin. The existing
facilities are all well established to meet the needs of the agricultural community.

H2.   BARRON RIVER CANAL NORTH BASIN

    Description of Basin
The Barron River Canal North Basin is located in north central Collier County to the east and
southeast of Immokalee. The basin generally follows the direction of SR-29 south from
Immokalee and terminates where the Okaloacoochee Slough flows westward under SR-29 and
into the Fakahatchee Strand. There are approximately 50 square miles of wetlands, agricultural
lands, and the isolated urban designated area of Immokalee within this basin.

The Barron River Canal North Basin is bounded on the west by the Corkscrew Slough Basin
and the Fakahatchee Strand Basin. The Okaloacoochee Slough Basin forms the northern,
eastern, and southern boundaries for this basin.

     Historical Background
The establishment of this basin began in the 1920’s with the construction of SR-29 and its
accompanying borrow canal between Immokalee and the City of Everglades. Agricultural dikes


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       Collier County Hazard Mitigation Plan                                             April 15, 2005



and ditches generally establish the boundaries to the east and west while drainage facilities
within Immokalee form the headwaters.

       Description of Existing Facilities
The major drainage facility within this basin is the Barron River Canal North that was excavated
in the 1920's during the construction of SR-29. This secondary canal is approximately 12 miles
in length with a branch secondary canal of approximately 4 miles in length extending around the
Immokalee Airport. The Barron River Canal North also receives runoff from approximately 3
miles of secondary canals within the Urban Immokalee Basin. The Barron River Canal North
discharges into the intersection of the Okaloacoochee Slough and the Barron River Canal.
There are currently no water level control structures within the canal system of this basin.

      Existing Condition/Capacity of Facilities
As previously mentioned, the Barron River Canal North and the secondary canals within
Immokalee have been in existence for many years. The maintenance of these canals is
performed by the Collier County Road Maintenance Department and primarily consists of the
control and removal of aquatic vegetation when this becomes excessive and hinders the flow of
stormwater through the system. Some sediment removal work is also done to return the
channel to its approximate original cross section when excess sediment accumulations become
a problem. The canals are of generally sufficient size to provide the desired level of service for
flood protection

       Proposed Improvements
There are no major modifications or improvements proposed for the canal. The County is
replacing several of the existing private culverted roadway crossings that are in various stages
of collapse along the canal. The County is also initiating the necessary engineering design and
plans preparation to replace one water level control structure at the Sunniland rock quarry
entrance that was destroyed by high water conditions in 1995.

H3.   URBAN IMMOKALEE BASIN

      Description of Basin
The Urban Immokalee Basin is a small area encompassing the urbanized community of
Immokalee in the north central portion of the County. This area contains the highest land
elevations in the northern portion of the County. The basin contains approximately 4 square
miles of urbanized land with various land uses including commercial, residential, and a portion
of vacant airport land. The Urban Immokalee Basin is bounded on the west and south by the
Corkscrew Slough Basin, on the east by the Barron River Canal North Basin, and on the north
by lands draining into Hendry County.

       Historical Background
Immokalee is an older community that centers on the agricultural industry. The ground
gradually slopes away from the community in all directions and the drainage swales excavated
with the gradual expansion of the urbanized area reflect this. Flows are directed in all directions
to the surrounding basins.

      Description of Existing Facilities
There are very few secondary canals within the Urban Immokalee Basin. Most of the basin’s
stormwater runoff is handled by numerous interconnected roadside swales. There are two
separate secondary canals identified within the basin with a total length of approximately 4
miles. There are no publicly maintained water level control structures within this basin.


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       Collier County Hazard Mitigation Plan                                           April 15, 2005




       Existing Condition/Capacity of Facilities
The secondary canal that provides a stormwater outfall for most of the northern half of
Immokalee discharges into the upper end of the Barron River Canal North. This small
secondary canal is generally insufficient in size to provide an adequate level of flooding
protection to the community in times of intense rainfall. Complicating this condition is the
amount of debris thrown into the canal by local residents. The maintenance of this canal is
performed by the Collier County Road Maintenance Department and primarily consists of the
control and removal of aquatic vegetation and debris when this becomes excessive and hinders
the flow of stormwater through the system. Some sediment removal work is also done to return
the channel to its approximate original cross section when excess sediment accumulations
become a problem.

The secondary canal that provides a stormwater outfall for some of the south central portion of
Immokalee discharges into the Corkscrew Slough Basin along the eastern side of Lake Trafford.
This small secondary channel is really nothing more that a slightly larger roadside swale and
pipe combination that is generally insufficient in size to provide an adequate level of flooding
protection to the community in times of intense rainfall. The Collier County Road Maintenance
Department and the Road and Bridge Section of the Transportation Department jointly perform
the maintenance of this channel. Maintenance primarily consists of the control and removal of
aquatic vegetation and debris when this becomes excessive and hinders the flow of stormwater
through the system. Some sediment removal work is also done to return the channel to its
approximate original cross section when excess sediment accumulations become a problem.

      Proposed Improvements
There are no major modifications or improvements proposed for the canals in this basin. The
County is replacing an existing culverted roadway crossings leading to the airport, and several
old culverts that were no longer needed have been removed.

H4.   BARRON RIVER CANAL BASIN

      Description of Basin
The Barron River Canal Basin is a large watershed area located in the south central part of
Collier County. The western boundary of this basin is approximately one half mile west and
parallel to SR-29 and the basin contains approximately 110 square miles of wetlands. The
basin is bound by the Okaloacoochee Slough Basin to the north, the Fakahatchee Strand Basin
to the west, the Everglades National Park estuary to the south, and the Turner River Basin to
the east.

The northern portion of the Barron River Canal Basin contains the East Hinson Marsh while the
southern portion contains the Deep Lake Strand and several prairie lands along SR-29. Most of
the basin is located within the boundaries of the Big Cypress National Preserve and the Big
Cypress Wildlife Management Area. There is very limited settlement within this basin and most
of this is located in the small communities along SR-29 including Copeland, Deep Lake,
Jerome, and Carnestown. The only development activities within this basin are a few rock-
mining pits, also located near SR-29.

     Historical Background
The establishment of this basin began in the 1920’s with the construction of SR-29 and its
accompanying borrow canal between Immokalee and the City of Everglades. The gradual slope



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       Collier County Hazard Mitigation Plan                                               April 15, 2005



of the land and the estimated region of sheetflow influence caused by the canal generally
establish the boundaries to the east and west.

       Description of Existing Facilities
The major drainage facility within this basin is the SR-29 borrow canal known as the Barron
River Canal. This canal is approximately 24 miles long, was excavated in the 1920's during the
construction of SR-29. Between I-75 and US-41 there are 8 flashboard type water level control
structures to reduce the over drainage of the adjacent land. This canal receives some
discharge from the Okaloacoochee Slough to the north as well as the surface drainage from the
wetlands within the basin. The canal eventually discharges into the Everglades estuary at the
incorporated community of the City of Everglades. The borrow canal along I-75 also discharges
into the Main Barron River Canal.

       Existing Condition/Capacity of Facilities
As previously mentioned, the Barron River Canal has been in existence for many years. The
maintenance of that portion of this canal north of I-75 is performed by the Collier County Road
Maintenance Department and primarily consists of the control and removal of aquatic vegetation
when this becomes excessive and hinders the flow of stormwater through the system. Some
sediment removal work is also done to return the channel to its approximate original cross
section when excess sediment accumulations become a problem. South of I-75 the Big
Cypress Basin is currently responsible for the maintenance and operation of the eight water
level control structures, but no agency is maintaining the canal. The canal and water level
control structures are of generally sufficient size to provide the desired level of service for flood
protection.

      Proposed Improvements
There are no major modifications or improvements proposed to the canal. The County is
currently attempting to gain the cooperation of a landowner for the replacement of a culverted
canal crossing that is in a bad state of repair. It is anticipated that the Big Cypress Basin will
also cooperate in this replacement activity. The National Park Service is expected to gain
control of the canal south of I-75 in the future, and a responsible agency may then be
determined for the canal maintenance.

I.    MISCELLANEOUS INTERIOR WETLAND SYSTEMS

The Miscellaneous Interior Wetland Systems is a generalized description of the various portions
of Collier County that cannot be included in any of the previously described basins. They are
generally located in the eastern portion of the County and are basins made up of wetlands and
other developed property. There are six basins that have been included within this system as
follows:

      I1.      Corkscrew Slough Basin
      I2.      Gator Hook Strand Basin
      I3.      L-28 Tieback Basin
      I4.      Turner River Canal Basin
      I5.      Fakahatchee Strand Basin




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       Collier County Hazard Mitigation Plan                                            April 15, 2005



Previous Studies
In the past, some of these basins have been studies for special purposes or applications.
Therefore, any references to studies will be included as a separate section within the
descriptions of the basins.

I1.   CORKSCREW SLOUGH BASIN

      Description of Basin
The Corkscrew Slough Basin, located in the northern portion of Collier County west of
Immokalee, is a very large drainage area that also includes portions of Lee County. This basin
is approximately 45 square miles in area and contains large areas of designated wetlands as
well as agriculture and some small amounts of residential and commercial land use, principally
in Immokalee. The major land feature of the basin is the Corkscrew Swamp. This drainage
basin is bound by a meandering natural drainage divide along the north, the Cocohatchee River
Basin to the west, CR-846 (Immokalee Road) to the south and southeast, and various drainage
controls in Immokalee. A listing of the PUD's and their status can be found in Appendix II of this
Section.

      Historical Background
The Corkscrew Slough Basin receives stormwater runoff from the Immokalee high area.
Various attempts have been made in the past to utilize some of the land for agriculture, but the
continual presence of large amounts of surface water has kept most of the basin undeveloped.
The large natural Lake Trafford provides some revenue for the area from the sport fishing
interests.

       Description of Existing Facilities
The principal identifying drainage feature of this drainage basin is the topography. The land
surface is generally a large shallow depression area that drains into Lake Trafford and ultimately
into the Corkscrew Swamp. Since this is a depressed area, the stormwater collects and pools
in the wetland areas for extended time periods until it either percolates into the groundwater
system or returns to the atmosphere via evaporation or transpiration. Only during extended
periods of excessive rainfall does this drainage basin overflow in a southwesterly direction into
the Cocohatchee River Canal Basin. There are no sizable man made drainage facilities within
this basin and all flow is directed by natural wetland drainage systems.

      Existing Condition/Capacity of Facilities
Since this drainage basin is almost entirely controlled by natural wetland drainage systems
there is very little maintenance required to be performed by the Collier County Road
Maintenance Department. Some minor drainage swales and canals in Immokalee are also
maintained for aquatic vegetation control and sediment removal when necessary. The natural
systems easily handle the volumes of stormwater runoff, and occasional aquatic vegetation
control is performed at Lake Trafford by the Big Cypress Basin.

     Proposed Improvements
There are no plans for any major improvements within this sub-basin.

I2.   GATOR HOOK STRAND BASIN

      Description of Basin
The Gator Hook Strand Basin is a very large drainage basin located in the far southeast corner
of Collier County and also extending into Broward, Dade, and Monroe Counties. Approximately


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       Collier County Hazard Mitigation Plan                                            April 15, 2005



153 square miles of Collier County are included in this basin. The land is typically a wet marl
prairie with scattered islands of pinelands. There is a very limited amount of development in this
basin within Collier, Broward, Dade, and Monroe Counties.

Within Collier County the Gator Hook Strand Basin is separated from the Turner River Canal
Basin by a slight change in elevation that is imperceptible to the eye, but discernable by aerial
views of the vegetative communities. The basin is bounded to the north by the L-28 Tieback
Basin and is separated from this northern basin by minor elevation changes and the L-28 Canal.
Sheetflow out of this basin either passes southward beneath US-41 into the Miscellaneous
Coastal Basin area or eastward into Broward and Dade Counties where it enters into the
Everglades National Park. Most of the Collier County portion of the Gator Hook Strand Basin
can be described as an inaccessible wilderness.

     Historical Background
The majority of the Collier County portion of this basin has had almost no settlement influence
by man. The construction of US-41 provided access through the basin and there was an
attempt to construct a large airport in the southeastern corner of the basin. Overall, there has
been very minimal impact on the natural drainage conditions of the basin.

       Description of Existing Facilities
The only drainage facilities that have been constructed in this drainage basin are the borrow
canal that was excavated to provide the roadbed fill material for US-41 and the drainage
excavation associated with the proposed airport. There are many cross drains beneath US-41
to allow for the stormwater to pass from the north to the south, but since the average ground
slope in this area is approximately 4 inches per mile, the movement of water is almost
imperceptible.

      Existing Condition/Capacity of Facilities
The borrow canal and roadway cross drains along US-41 were designed to approximate the
original sheetflow conditions of this area. The condition of the canal and cross drains is
generally good and the capacities sufficient to prevent major backup above the roadway surface
of any surface water from the typical storm events. The maintenance of this canal is performed
by the Florida Department of Transportation and primarily consists of the control and removal of
aquatic vegetation when this becomes excessive and hinders the flow of stormwater through the
system. Some sediment removal work is also done to return the channel to its approximate
original cross section when excess sediment accumulations become a problem.

       Discussion of Previous Studies
The three engineering studies described in the Turner River Basin section of this Sub-Element
also include the Gator Hook Strand Basin. No additional studies have been prepared since
1963 and no significant developmental improvements have taken place in this basin since then.

      Proposed Improvements
The Collier County portion of the Gator Hook Strand Basin is essentially a wilderness area and
there are no current plans to create any new drainage improvements.

I3.   L-28 TIEBACK BASIN

      Description of Basin
The L-28 Tieback Basin is a very large drainage basin located in the east northeast corner of
Collier County and also extending into Hendry and Broward Counties. Approximately 177


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       Collier County Hazard Mitigation Plan                                               April 15, 2005



square miles of Collier County are included in this basin. The land is typically a wet marl prairie
with scattered islands of pinelands. There is a very limited amount of development in this basin
within Collier, and Broward Counties. The northern portion of the basin, located in Hendry
County, has been more highly developed for agricultural purposes.

Within Collier County the L-28 Tieback Basin is separated from the Turner River Canal Basin by
a low ridgeline in an area known as the "stairsteps". This ridgeline diverts the sheetflow of
stormwater toward the east into Broward and Dade Counties from where it then flows south into
the Everglades National Park. The L-28 Tieback Basin is bounded on the south by the Gator
Hook Strand Basin. The “stairsteps and the L-28 Canal forms the division between the L-28
Tieback and Gator Hook Strand Basins. Most of the Collier County portion of the L-28 Tieback
Basin can be described as an inaccessible wilderness. Since most of the L-28 Tieback Basin is
located outside the Collier County limits and the portion of Collier County that is within this basin
is undevelopable at this time, there does not appear to be any need to determine the
proportional capacity analysis for any shared systems at this time.

       Historical Background
The majority of the Collier County portion of this basin has had almost no settlement influence
by man. As a part of the extensive canal system created by the old Central and Southern
Florida Flood Control District, a section of the L-28 Canal and Levee extends from Broward
County into the northeast corner of the basin within Collier County. The construction of I-75
(Alligator Alley) provided east/west access through the center of the basin. There are some
Indian reservation settlements, but these have had very minimal impact on the natural drainage
conditions of the basin.

       Description of Existing Facilities
The only publicly maintained drainage facilities that have been constructed in this drainage
basin are the borrow canal that was excavated to provide the roadbed fill material for I-75
(Alligator Alley) and the short section of the L-28 Canal extending from Broward County. The
L-28 Canal is a part of the South Florida Water Management District (SFWMD) flood control
program for Broward and Dade Counties.

      Existing Condition/Capacity of Facilities
The condition of the canal is good and the capacity sufficient to prevent major flooding. The
L-28 Canal was designed to provide flood protection for the neighboring counties and exceeds
any level of service standards for the Collier County water management requirements. The
maintenance of this canal is performed by the SFWMD and primarily consists of the control and
removal of aquatic vegetation when this becomes excessive and hinders the flow of stormwater
through the system. Some sediment removal work is also done to return the channel to its
approximate original cross section when excess sediment accumulations become a problem.

       Discussion of Previous Studies
The three engineering studies described in the Turner River Basin section of this Sub-Element
also include the L-28 Tieback Basin. No additional studies have been prepared since 1963 and
no significant developmental improvements have taken place in this basin since then.

      Proposed Improvements
The Collier County portion of the L-28 Tieback Basin is essentially a wilderness area and there
are no current plans to create any new drainage improvements.

I4.   TURNER RIVER CANAL BASIN


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       Collier County Hazard Mitigation Plan                                             April 15, 2005




       Description of Basin
The Turner River Canal Basin is located in the southeastern portion of Collier County and much
of this basin is within the boundaries of the Big Cypress National Preserve Area. The land is
typically a wet marl prairie with scattered islands of pinelands. There is a very limited amount of
development or the establishment of dwellings within this basin and most of the area can be
classified as an inaccessible wilderness. The total area of this basin is approximately 362
square miles of which approximately 44 square miles is in Hendry County. The proportional
capacity of the system contributed by Hendry County is still unknown even after the completion
of the Collier County Stormwater Management Master Plan.

      Historical Background
Except for the Ochopee area, this basin has had almost no settlement influence by man and
except for the construction of I-75 and US-41, the area is essentially an uninhabited wilderness
crisscrossed by numerous swamp buggy trails.

      Description of Existing Facilities
The only drainage facilities that have been constructed in this drainage basin are the borrow
canals that were excavated to provide the roadbed fill material for I-75 (Alligator Alley), US-41
(Tamiami Trail), and CR-839 (Turner River Road). I-75 and US-41 are east-west roads and
there are many roadway cross drains beneath each of these roads that allow for the stormwater
to pass from the north to the south, but since the average ground slope in this area is
approximately 4 inches per mile, the movement of water is almost imperceptible. CR-839 is a
north-south road that extends from US-41 to approximately 3 miles north of I-75. The borrow
canal along the east side of this road provides a drainage outlet for the western edge of the
Turner River Basin.

      Existing Condition/Capacity of Facilities
The borrow canals and roadway cross drains along both I-75 and US-41 were designed to
approximate the original sheetflow conditions of this area. The condition of the canals and
cross drains is generally good and the capacities sufficient to prevent major backup above the
roadway surface of any surface water from the typical storm events. Any maintenance to these
canals or cross drains is performed by the Florida Department of Transportation.

The Turner River Canal is being allowed to slowly return to the pre-construction status of
vegetation stand. One set of corrugated metal cross drains was installed in cooperation with the
National Park Service to try to route the stormwater flow back into the original Turner River
stream bed. This section of the river is being allowed to accumulate excessive aquatic
vegetation growth and thus restrict the flow of stormwater from the land into the estuary. Its
capacity will eventually return to that of the surrounding lands.

      Discussion of Previous Studies
A search of the Collier County Stormwater Management files lists three engineering studies that
have been prepared for the portion of the County included in the Turner River Canal Basin. The
study that best describes this area is titled "Exploratory Drainage Study of Eastern Collier
County" and was prepared by Smally, Wellford, and Nalven in June 1962. Smally, Wellford, and
Nalven also prepared the other two studies and are titled "Report on Proposed Drainage and
Road Improvements in Southeastern Collier County" prepared in November 1962, and "Water
Management in Western Collier County and a Proposed Water Conservation District" prepared
in June 1963. All three studies emphasized the extreme flatness of the drainage area and the



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       Collier County Hazard Mitigation Plan                                              April 15, 2005



lack of development or habitation. Since the time of these studies, little or no significant
developmental improvements have taken place in the Turner River Basin.

      Proposed Improvements
Almost all of the area of Collier County contained in the Turner River Canal Basin is a part of the
Big Cypress National Preserve. This is a wilderness area and there are no current plans to
create any new drainage improvements.

I5.   FAKAHATCHEE STRAND BASIN

      Description of Basin
The Fakahatchee Strand Basin is a large, natural drainage basin located in the south central
portion of Collier County. This basin encompasses approximately 197 square miles of wetland
with some extensive agricultural operations located in the northern part of the basin. The basin
is bound by the Corkscrew Slough Basin and the Barron River Canal North Basin to the north,
the Faka-Union System basins to the west, US-41 and the Fakahatchee Bay estuary to the
south, and the Barron River Canal Basin, the Okaloacoochee Slough Basin, and the Barron
River Canal North Basin to the east. The Fakahatchee Strand State Preserve and most of the
Florida Panther State Wildlife Preserve are also contained within this basin.

       Historical Background
Prior to any alteration of the drainage patterns within Collier County, the Fakahatchee Strand
was a major flow way for surface waters from most of central Collier County and western
Hendry County. The Okaloacoochee Slough was a major contributor to the stormwater supply
to the Strand. Stormwater traveled as sheetflow through vast forests of cypress and other
wetland environments and eventually discharged into the Fakahatchee Bay estuary.

The first major change in the Fakahatchee Strand area occurred with the construction of SR-29
along what is now the eastern boundary of the basin. This highway and accompanying borrow
canal (the Barron River North and Barron River Canals) acted as a dike and diversion channel
to reduce the inflow of water from the Okaloacoochee Slough area. The construction of CR-846
(Immokalee Road) also diverted some traditional southward flows from the Lake
Trafford/Corkscrew Swamp area. The construction of the Faka-Union System by the Gulf
America Corporation further reduced the inflow of any water from the west and, as recent
studies have shown, actually worked to withdraw stormwater from the Strand. Thus the present
basin boundaries of the Fakahatchee Strand have essentially been limited by the various
construction projects for surrounding areas.

Within the Fakahatchee Strand Basin, extensive timbering operations in the 1950's were
conducted to harvest the cypress forests. This timbering utilized logging trams and the
numerous railroad grades created by these operations have also contributed to a diversion of
the traditional sheetflow of surface water so that artificial uplands have been created.

      Description of Existing Facilities
The Fakahatchee Strand is a large natural drainage flow way that has not been developed for
residential purposes. The only development has been for some large agricultural operations in
the northern limits of the basin. No drainage facilities have been constructed within this basin
except for the borrow canal along I-75 (Alligator Alley). This canal intercepts the southerly
sheetflow and passes it beneath I-75 through various cross drains where it resumes the
sheetflow toward the estuary.



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      Existing Condition/Capacity of Facilities
The existing borrow canal along I-75 and the accompanying cross drains were designed to
approximate the original sheetflow conditions of this area and provide adequate capacity for the
passage of surface water through the Fakahatchee Strand. The condition of the canal and
cross drains is generally good and the capacities sufficient to prevent major backup above the
roadway surface of any surface water from the typical storm events. Any maintenance to this
canal or the cross drains is performed by the Florida Department of Transportation.

       Discussion of Previous Studies
Several studies have been completed to evaluate the impacts to the Fakahatchee Strand which
may have been caused by the development of surrounding lands. Some of these studies were
listed in the Faka-Union System section of this Sub-element. Two additional reports are
mentioned at this time.

The first report, "Final Report on the Augmentation of Surficial Flow Through the Fakahatchee
Strand, Collier County, Florida", was prepared by William J. McElroy with the Florida
Department of Environmental Regulation, and Captain K. C. Alvarez with the Florida
Department of Natural Resources in September, 1975. This report is also discussed in the
Barron River Canal Basin section of this Sub-element.

The second report, "The Effect of the Faka-Union Canal System on Water Levels in the
Fakahatchee Strand, Collier County., Florida", was prepared by the U.S. Geological Survey,
Water Resources Investigations 77-61 in September, 1977. This report evaluated the effects
that the eastern canals of the Faka-Union System were having on the surface and groundwater
profiles along the western boundary of the Fakahatchee Strand. The drawdown and removal of
stormwater from the Strand were demonstrated and the limited beneficial effects of the one
water level control structure were identified. This report identified the need to conduct further
studies into the use of flow blocks in the eastern Faka-Union System canals to raise and restore
water levels in the Strand.

     Proposed Improvements
There are no plans to improve the existing drainage facilities within the Fakahatchee Strand
Basin at this time.

J.    MISCELLANEOUS COASTAL BASINS

The Miscellaneous Coastal Basins is a generalized description of the various portions of Collier
County that are generally along the coastal estuarine region and have not been included in any
of the previously described basins. At this time this descriptive term includes a collection of the
following five areas:

      J1.      Miscellaneous Coastal
      J2.      Wiggins Bay Basin
      J3.      Naples Park North
      J4.      Naples Park South
      J5.      Collier-Seminole Park

As the County continues to update the database of stormwater management facilities, this
grouping is likely to increase in number.




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J1.   MISCELLANEOUS COASTAL

      Description of Basin
The region encompassed by this basin description varies but generally includes all drainage
areas between the coastal waters and the first major road inland. The greatest land covered by
this basin is in the southeastern portion of the County south of US-41, but there are no facilities
within this large area.

Along the coastline, the estuarine areas are divided into several hypothetical basin areas. Due
to tidal influences, no distinct boundaries can be established and the term basins is applied
loosely because no distinct flow directions or patterns can be established. These hypothetical
estuarine basins are the same as those established by the Collier County Department of Natural
Resources in their Technical Report 84-3 and 84-4. Intense development has occurred within
several of these estuarine basins and includes portions of the City of Naples, the City of
Everglades, Marco Island, Isle of Capri, the communities of Chocoloskee and Goodland, and
many existing and proposed PUD's including Barefoot Beach Condo, Little Hickory Bay, Bonita
Shores, Audubon Country Club, Bay Forest, Waterglades, Hawks Nest, Wiggins Bay, Vanderbilt
Villas, Vanderbilt Beach Estates, Vanderbilt Beach Community Center, portions of Pelican Bay,
Park Shore, Windstar, Jackson Gateway Harbor, portions of the Collier DRI, Treetops, Venician
Residence, Riverbend, Marco Shores, Marco Shores Country Club, Naples Shores, and Port of
the Islands. A listing of the PUD's and their status can be found in Appendix II of this Section.

      Historical Background
The history on the establishment of the various drainage facilities within this region is as diverse
as the facilities themselves. Much of the work was done by individual development activities
and/or attempts to control mosquitoes to surrounding regions. Where information is known, it is
included in the discussion of each individual set of facilities.

      Description of Existing Facilities
Generally speaking, the only public drainage facilities located within these areas are small
ditches, culvert pipes, or some canals excavated to obtain fill material for the construction of
roadways. These are all located in the estuarine basins where the discharge is affected more
by tidal influence than by rainfall intensity. The numerous developments and PUD's contain
internal drainage facilities which, depending upon the age of the development, are designed
either for a 10-year or 25-year storm event.

As was stated previously for the Gordon River Basin, there are some very small areas that have
been identified where drainage transfers from the County to the City of Naples. One area is
along Sandpiper Street that is located on the east side of Naples Bay in the southern portion of
the City limits. A series of roadside swales or some short sections of storm sewer control
drainage along this street in the Royal Harbor area. The City limit extends to approximately
150' east of Sandpiper Street from the intersection of US-41 to Blue Point Ave. A small swale
along the back limits of the private lots prevents any drainage crossing into different
jurisdictional areas. From Blue Point Ave. to Marlin Drive the City limit is along the centerline of
Sandpiper Street. There are four (4) storm sewer inlets that collect runoff from the City and
County area near the intersection of Blue Point Ave. and Sandpiper Street. This short section of
storm sewer outlets into Naples Bay. A similar collection system is also located near the
intersection of Jewel Box Ave. and Sandpiper Street. From Marlin Drive southward, Sandpiper
Street is totally outside the City limits and all drainage flows into a swale leading to Haldeman
Creek.



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Another very small area where drainage crosses the City/County boundary is located along the
northern City limit line. Seagate Drive, borders this area on the north on the east by US-41, on
the south by the Naples City limit north of Neapolitan Way, and on the west by the Naples City
limit along West Blvd. There is an existing County storm sewer along the 4-lane portion of
Seagate Drive. This storm sewer receives the drainage from Seagate Drive and a small portion
of all the properties fronting on it. It also receives the drainage from the Seagate Elementary
school building and frontage area that is City property. This storm sewer empties into the bay
inlet west of Sand Dollar Ave. The interior portion of this area is very flat and drainage is poor in
some parts. The flow patterns are not easily defined but eventually outfall into Lake 1 within the
Naples City limit by means of small roadside swales and storm sewers along West Blvd. and
Neapolitan Way.

      Existing Condition/Capacity of Facilities
Generally, the drainage facilities are adequate to prevent flooding except when tidal conditions
disrupt or prohibit discharge into the Gulf. Very little maintenance is required on the roadside
canals except for cleanup of any blockages after a major storm.

An analysis of the drainage/water management facilities that affect both the County and the City
of Naples in the areas of Sandpiper Street and Seagate Drive produced the following
information. The drainage areas along Sandpiper Street are very small and difficult to define
near the existing storm sewer inlets. Due to the flat and very low lying terrain, the runoff
contributed by the County to City storm sewer drainage facilities in only approximately 1 cfs for
each of the inlets. The volume of runoff contributed by the City to County drainage facilities is
approximately 2 cfs and occurs at the intersection of Sandpiper Street and Marlin Drive.

In the Seagate Drive area, the volume of runoff contributed to the County storm sewer drainage
controls along Seagate Drive from the City drainage areas is approximately 3 cfs. The volume
of runoff contributed to the City drainage controls from the interior portions of this area is
approximately 18 cfs.

      Proposed Improvements
The only improvements planned for the drainage facilities within any of these areas are those
within the various proposed developments. As these proposals are submitted for permit review
and approval they will be evaluated for their effects on the existing drainage facilities and the
incorporation of any major basin outfalls that may be applicable.

J2.   WIGGINS BAY BASIN

      Description of Basin
The Wiggins Bay Basin is a small, but separate drainage area located northwest of the
Cocohatchee River Basin in northwestern Collier County. This basin is approximately 2.4
square miles in size and is bound by the Cocohatchee River to the south, old US-41 and the
Cocohatchee River Canal Basin to the east, natural drainage divide features to the north, and
Vanderbilt Drive to the west. Several residential PUD's are developed or proposed for this
basin including The Retreat, Bentley Village, Wiggins Lake, Tarpon Cove, Cypress Head, part of
Audubon Country Club, Lawmetka Plaza and Village Place. A listing of the PUD's and their
status can be found in Appendix II of this Section. Except for the PUD's, the land within this
basin is a mixture of undeveloped coastal pineland and wetland.

      Historical Background



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The boundaries of the Wiggins Bay Basin were established by construction of roads and
developments in the area. It appears that the existing small drainage canal that traverses
through the basin was excavated at about the time of the modification of US-41.

      Description of Existing Facilities
The only drainage facility, other than the water management facilities within the limits of the
PUD's, is a small secondary canal, approximately 1 mile in length, which discharges into the
Cocohatchee River via the Gulf Harbor development canal system. There are no water level
control structures within this basin.

        Existing Condition/Capacity of Facilities
The condition of the drainage facilities within this basin are generally insufficient to meet the
water management needs of this basin. The Collier County Road Maintenance Department is
responsible for the performance of maintenance to the one canal to control and remove aquatic
vegetation when this becomes excessive and hinders the flow of stormwater through the
system. However, at this time, no maintenance is being done, due to the inaccessibility of the
facility for lack of a drainage easement.

       Proposed Improvements
The County is currently developing a Basin Master Plan for the Wiggins Bay Basin to provide
direction for the stormwater needs of future development activity. Additionally, developer
contributions are helping provide the necessary drainage easements to allow for necessary
maintenance activities to the facilities.

J3.   NAPLES PARK NORTH BASIN

      Description of Basin
The Naples Park North Basin is a small drainage basin in northwestern Collier County. This
basin is approximately 0.6 square miles in size and is composed of urban residential and
commercial land uses. It contains the northeast quarter of the Naples Park Subdivision and the
land due north to the Cocohatchee River. The basin is bounded by US-41 to the east, the
Cocohatchee River to the north, a natural drainage divide to the west of and parallel to 7th
Street, and a second natural drainage divide along 101st Avenue to the south which separates
the Naples Park North and Naples Park South Basins. A listing of the PUD's and their status
can be found in Appendix II of this Section.

      Historical Background
The Naples Park North Basin was established in the late 1950’s when the subdivision was laid
out and the drainage swales created.

      Description of Existing Facilities
The Naples Park Subdivision is constructed with roadside swales along the avenues which
discharge into collector ditches along the streets. The major collector ditch is located along 8th
Street. For the Naples Park North Basin, the outlet canal for the collector ditches is
approximately 0.5 miles in length, is located at the northern end of 8th Street, and discharges
through an area proposed for a PUD. The ultimate discharge of the proposed PUD will be
through a spreader system into the Cocohatchee River.

      Existing Condition/Capacity of Facilities
The present capacity of the Naples Park North drainage outfall system is generally insufficient to
pass the volume of stormwater required by the level of service standard for this basin. One of


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       Collier County Hazard Mitigation Plan                                              April 15, 2005



the major problems is the restriction caused by small culvert pipes and flat topography. The
maintenance of this outfall system is performed by the Collier County Road Maintenance
Department and primarily consists of the control and removal of aquatic vegetation when this
becomes excessive and hinders the flow of stormwater through the system. Some sediment
removal work is also done to return the channel to its approximate original cross section when
excess sediment accumulations become a problem.

      Proposed Improvements
In September 1996, the County contracted to install a major storm sewer system to replace the
ditched outfall system along 8th Street North. This work will enable the basin to provide a 10-
year design storm level of service. Additional swale maintenance is currently scheduled to
follow up after completion of the storm sewer installation in April 1997. The northern outfall
channel is being increased in size to provide sufficient outlet capacity until such time that the
PUD planned for the area is constructed.

J4.   NAPLES PARK SOUTH BASIN

      Description of Basin
The Naples Park South Basin is another small drainage basin in northwestern Collier Oounty.
This Basin is approximately 0.9 square miles in size and is composed of urban residential and
commercial land use. It contains the southern half of the Naples Park Subdivision, and the
Beachwalk, Pavilion Commercial, and Pavilion Lake PUD’s. A listing of the PUD's and their
status can be found in Appendix II of this Section. The basin is bounded by US-41 to the east, a
natural drainage divide along 101st Avenue to the north that separates the Naples Park North
and Naples Park South basins, Vanderbilt Drive to the west, and Vanderbilt Beach Road to the
south.

      Historical Background
The Naples Park South Basin was established in the late 1950’s when the subdivision was laid
out and the drainage swales created.

       Description of Existing Facilities
The Naples Park Subdivision was constructed with roadside swales along the avenues which
discharge into collector ditches along the streets. The major collector ditch is approximately 0.6
miles long and is located along the east side of 8th Street. For the Naples Park South Basin,
the outlet for the collector ditches is a large ditch between 91st and 92nd Avenues. This outlet
ditch is approximately .8 miles in length and discharges into Vanderbilt Lagoon through a cross
drain consisting of a twin 3' x 7' box culvert beneath Vanderbilt Drive. The Pavilion PUD
discharges into this outlet ditch at 8th Street and the Beachwalk PUD discharges into the outlet
ditch at Vanderbilt Drive.

       Existing Condition/Capacity of Facilities
The present capacity of the Naples Park South outlet ditch, because of its size, is generally
insufficient to pass the volume of water required by the level of service standard for this basin.
The maintenance of this outlet ditch is performed by the Collier County Road Maintenance
Department and primarily consists of the control and removal of aquatic vegetation when this
becomes excessive and hinders the flow of stormwater through the system. Some sediment
removal work is also done to return the channel to its approximate original cross section when
excess sediment accumulations become a problem.

      Proposed Improvements


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       Collier County Hazard Mitigation Plan                                             April 15, 2005



In September 1996, the County contracted to install a major storm sewer system to replace the
ditched outfall system along 8th Street North and between 91st Avenue North and 92nd Avenue
North. This work will enable the basin to provide a 10-year design storm level of service.
Additional swale maintenance is currently scheduled to follow up after completion of the storm
sewer installation in April 1997.

J5.   COLLIER SEMINOLE PARK

       Description of Basin
This coastal basin is essentially the same as most of the other Miscellaneous Coastal Basins
except that it is located directly downstream from the Collier Seminole State Park. The basin is
all coastal wetland and has no definitive eastern or western boundaries. It is bounded on the
north by the Collier Seminole Outlet Basin and on the south by the Gulf of Mexico.

      Historical Background
The decision to define this area as a separate basin was made by the consultant engineering
firm when preparing the Collier County Stormwater Management Master Plan.

      Description of Existing Facilities
This basin is bisected by SR-92 and contains one cross drain and the typical roadside borrow
canal. Maintenance to these roadway drainage facilities is provided by the Florida Department
of Transportation. Maintenance primarily consists of removal of sediments when these become
a hindrance to flow. With the tidal flushing, accumulation of aquatic vegetation is generally not a
problem.

      Existing Condition/Capacity of Facilities
The one cross drain generally provides adequate capacity for the passing of stormwater from
the upstream Collier Seminole Outlet Basin.

     Proposed Improvements
There are no proposed improvements to the drainage facilities within this basin.

K.    OTHER MINOR AREAS OUTLETTING DIRECTLY INTO ADJACENT COUNTIES

      Description of Basin
This section contains a generalized description of additional small portions of Collier County that
cannot be included in any of the previously described basin sections. These areas can be
located on the Major Drainage Basins, Collier County, Florida map located in the Appendix of
Section 1 of this Element. There are two small areas along the northern County line near Lake
Trafford where surface water flows from Collier County into Hendry County and eventually into
Lee County. There is also a small area along the northwest northern County line between I-75
and US-41 where surface water flows from Collier County into Lee County. These areas are
wetlands that have not been developed at this time.

      Historical Background
The establishment of these small isolated wetlands has occurred through agricultural and other
development activity. These wetlands are connected to wetlands in adjacent counties and are
so minor in comparison to the overall adjoining wetlands that their contributory impact is
negligible.




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Description of Existing Facilities
There are no publicly maintained drainage facilities located within these areas.

     Existing Condition/Capacity of Facilities
There is no information that can be inserted into this section.

     Proposed Improvements
There are no proposed improvements within these small areas.

L.     CITY OF NAPLES DRAINAGE SYSTEM

The City of Naples drainage system consists primarily of swales, ditches, canal basins located
in twelve drainage basins. In 1991, a Stormwater Utility Tax was implemented to ensure the
system remained functional and reliable. Currently the tax generates $1.4 million annually to
fund the operation of the Stormwater Maintenance Department, routine inspections,
maintenance and repair of equipment and operation of the City street sweeper. In addition, the
stormwater tax funds the annual lake maintenance program for the control of aquatic weeds and
vegetation on 28 lakes throughout the City to ensure they continue to function as detention
areas.

All of the City’s stormwater facilities are inspected every six months and repairs are made
accordingly with concurrence from the Utility Director.

Daily operation of the City street sweeper reduces the amount of debris accumulation in the
storm water system.

City of Naples
Major Basin and Sub-Basin Identification

In order to determine the hydrology of a given area, it is necessary to determine the major storm
water basin boundaries. This was accomplished in the1990 draft report of the Storm Water
Master Plan. The City’s major stormwater system boundaries were depicted in the major storm
water drawing.

Each of the boundaries were field verified and compared to existing system locations and, in
some cases, were modified to reflect current conditions. The City’s inventory of storm sewer
system was also added on a storm water facility inventory map. Minor basin boundaries and
sub basin boundaries were added from current available information, and then crossed checked
and revised to agree with the storm sewer system inventory. The boundaries were modified
based on field review, storm sewer pipe and inlet location, and stormwater management design
experience. Drainage Sub-Basin boundaries were also determined from roadway drainage
maps (U.S. 41 Goodlette Frank Road, etc.) as well as from storm sewer pipe inlet location and
storm water management design experience.

The major basin descriptions are as follows:

Basin I:
This basin is bounded by the Gulf on the west, Seagate Drive on the north, US-41 on the east
and a line that extends from Doctors Pass through the Moorings country Club to US-41 on the
south. The land is characterized primarily by residential development in the Park Shore Area.



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The basin’s storm water runoff is routed via a series of swales, inlets, pipes and detention lakes
that discharge into Moorings Bay.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin II:
This basin is bounded by the Gulf on the west, Basin I on the north, US-41 and Basin V on the
east, and a line that runs from the intersection of 4th Ave. South and the beach northeasterly to
the southeasterly corner of the Naples Beach Club Golf Course on the south. The land use is
characterized primarily by residential development with commercial development along the US
41 corridor and multi-family high-rise residential and hotel development along the Gulf beaches.
The northern portion of the basin discharges its stormwater runoff via swales, inlets, pipes and
detention lakes to the Gulf of Mexico.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin III:
This basin is bounded by the Gulf on the west, Basin II and Basin VI on the north, Naples Bay
on the east, and a line running from the Naples Pier southerly to Naples Bay on the south. The
land use is characterized primarily by residential development with commercial development in
the 5th Avenue South, 3rd Street South and Crayton Cove areas. Additionally, Naples City Hall
and Fire Station 1 are located in this basin. The basin’s stormwater runoff is routed via swales,
inlets and pipes and one detention lake to the Broad Avenue south storm water pump station for
discharge into Naples Bay.

Proposed Improvements:
Basin III:
Recommended Alternative No. 3: Total Probable Construction Cost $6.3 Million:
The scope of stormwater infrastructure improvements consists of additional storm sewers for
increasing flow capacity to reduce street flooding, and also upgrades to the existing pump
station with the pump capacity remaining status quo. With one exception, the improvements
associated with Alternative 3 will keep floodwaters at least 2 inches below the road crown under
the 2-year 24-hour design storm event. The one exception occurs at the intersection of 9th
Avenue South and 10th Street South because the crown of the road at this junction is at the
same elevation as the tide conditions modeled for Naples Bay. As a slight modification to
alternative 3, the City could elect to reconstruct the subject intersection and adjoining street
segments to attain the prescribed level of service for the entire basin area.

Storm sewer construction involves replacement of existing pipelines and additionally the
installation of new storm sewers adjacent and parallel to existing pipelines. Storm sewer sizes
range from 24-inch diameter to 5 foot by 8-foot box culverts.

Basin IV:
This basin is bounded by the Gulf on the west, Basin III on the north and Naples Bay on the
east and south. The land use is characterized by the Port Royal and Aqualane Shores


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residential developments. The basin’s stormwater runoff is routed via swales, inlets and pipes
to the canals of the basin, which flow to Naples Bay. There is a stormwater pump station
located on Lantern Lane in Port Royal.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin V:
This basin is bounded by US-41 and Basin II on the west, Creech Road on the north, Goodlette-
Frank Road on the east and a line that runs from the intersection of US-41 and 3rd Ave. North,
northerly to Goodlette-Frank road on the south. The land is characterized by commercial
development along the US-41 corridor including the Coastland Mall area with residential
development throughout the basin. The basin’s stormwater runoff is routed via swales, inlets,
pipes and several detention lakes to a storm sewer pipe system along the west right-of-way of
Goodlette-Frank Road. This system discharges into the Gordon River.

Proposed Improvements

Basin V: Study In Progress –
Final Recommended Alternative Not Yet Issued. Cost Evaluation Not Complete But Currently
Ranges Between $5-$8 Million:

The scope of stormwater infrastructure improvements consists of additional storm sewers and
water level control structures for increasing system flow capacity and attaining water quality
requirements.

This basin is under final engineering analyses with two alternatives being developed. Alternative
No. 1 involves capacity and water quality improvements as set forth in the Phase IV Gordon
River Extension Study with a prescribed level of service standard equating to a maximum of 6
inches of flooding above the road crown for rainfall depths resulting from a 25- year 72-hour
design storm event. Improvements designated under Alternative No. 1 are being developed to
principally address stormwater problems within the easterly Collier County drainage basins and
also along Goodlette-Frank Road. Notwithstanding that the Phase IV Gordon River Extension
Study improvements were not developed to specifically address Basin V flooding problems in
the City of Naples, the stormwater improvements under this alternative do have a significant
positive impact on the hydraulic performance of the Basin V system since proposed capacity
improvements to the channel along Goodlette-Frank Road comprise the primary outfall for Basin
V. Alternative No. 1 comprises of 21 distinct locations for replacement of existing storm sewers
and culverts within and east of the Goodlette-Frank road channel, widening segments of the
existing Goodlette-Frank road channel and also constructing a 27 acre stormwater detention
pond.

Alternative No. 2 provides for system wide stormwater improvements within Basin V to achieve
the City’s preliminary level of service goals for 25 drainage problem areas. Stormwater
infrastructure improvements under this alternative are intended to provide a Class B level of
service benefit or no overtopping of road crown for the 25-year 72-hour design storm event. This
level of service standard is more stringent that Alternative No. 1 which permits flooding of up to
6 inches above the road crown.



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Storm sewer construction under the Alternative No. 2 scenario involves extensive replacement
of existing pipelines and installation of new storm sewers within Basin V west of Goodlette-
Frank Road with no improvements within the channel adjacent to Goodlette- Frank Road as
such capacity improvements are designated in Alternative No. 1. The scope of work under
Alternative No. 2 comprises of 22 distinct locations for replacement of existing pipelines and
installation of new storm sewers adjacent and parallel to existing pipelines. Storm sewer sizes
range from 24-inch diameter to 4-foot by 10-foot box culverts.

Basin VI:
This basin is bounded by Basin II on the west, Basin V on the north, Goodlette-Frank Road on
the east, and Basin III on the south. The land use is characterized by primarily commercial
development on the US-41 corridor and downtown Naples area with residential development
interspaced throughout. The majority of the basin’s stormwater runoff is routed via swales,
inlets and pipes to the Goodlette-Frank Road stormwater pump station near the Police
Department. This system discharges into the Gordon River. A portion of the basin’s stormwater
run-off is routed via swales, inlets and pipes to a ditch and pipe system along the west right-of-
way along Goodlette- Frank Road. This system discharges into the Gordon River.

Proposed Improvements

Basin VI:
Recommended Alternative No. 3: Total Probable Construction Cost $3.2 Million:
The general scope of stormwater infrastructure improvements for Basin VI is similar in content
to that described for Basin III consisting of additional storm sewers along City streets for
increasing flow capacity to reduce wet season flooding. Stormwater improvements include
replacing existing storm sewer pipes to achieve greater flows such as along 2nd Avenue North
and 10th Street North, and also involve re-directing the storm sewer collection system along
Goodlette-Frank Road to the pump station system. A 4-foot by 8-foot box culvert is required as
the main trunk line from 10th Street to the relocated pump station and along 12th Street between
1st Avenue South and Central Avenue a 2-foot by 4-foot box culvert is proposed.

No locations within Basin VI would have system capacity less than that required to convey
rainfall resulting from a 10-year design storm event.

Basin VII:
This basin is bounded by Naples Bay on the west, U.S. 41 on the north, Sandpiper Street on the
east, and Naples Bay on the south. The land use is characterized by Royal Harbor, some multi
family residential development in the north portion of the basin, and some commercial
development along the US-41 corridor. The basin stormwater runoff is routed via swales, inlets
and pipes to canals of the basin, which flow to Naples Bay.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin VIII:
This basin is bounded by Goodlette-Frank Road on the west, an east west line that would be the
westerly extension of the north boundary of Naples Airport on the north and the Gordon River
on the east and south. The land use is characterized by some residential development in the
north portion of the basin with commercial development along the Goodlette-Frank Road


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       Collier County Hazard Mitigation Plan                                         April 15, 2005



corridor. The City Police and Emergency Services Department and the Goodlette-Frank Road
stormwater pump station are located within the basin. The basin’s stormwater runoff is routed
via swales, inlets and pipes into the Gordon River.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin IX:
This basin is bounded by Goodlette-Frank Road on the west, the Gordon River and Airport-
Pulling Road on the east and Basin VIII on the south. This basin is the City’s portion of the
Collier County “Gordon River Extension Stormwater Basin ”which extends well into the County.
The land use is characterized by residential development, some commercial development along
the Goodlette-Frank Road corridor and undeveloped land/preserve. The basin’s stormwater
runoff is routed via swales and overland sheet flow to the Gordon River.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin X:
The Gordon River bounds this basin on the west, the north boundary of Naples Airport (north),
Airport-Pulling Road on the east, and the south boundary of the Naples Airport and US-41 on
the south. Primarily the Naples Airport and some residential and commercial development
characterize the land use. The basin’s runoff is routed by swales, inlets, pipes, and overland
sheet flow to the Gordon River.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin XI:
This basin is bounded by Naples Bay on the west, Basin VII on the north, and the City limits on
the east and south. The land is undeveloped except for Bayview Park. The basin’s stormwater
runoff is routed via overland sheet flow to Naples Bay.

Proposed Improvements
An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

Basin XII:
This basin is the portion of Key Island within the City limits. The land is mostly undeveloped
with some residential development. The basin’s stormwater runoff is routed via overland sheet
flow to Naples Bay and the Gulf of Mexico.

Proposed Improvements



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       Collier County Hazard Mitigation Plan                                          April 15, 2005



An assessment of existing stormwater facilities and proposed improvements, including
provisions for water quality shall be performed as part of an upcoming Integrated Stormwater
Management Program and Master Plan.

There are two major basins within the county that directly affect the City of Naples. These are
the Gordon River Extension (GRE) and main Golden Gate (MGG). Both of these watersheds
are a major contributor of runoff which discharge unto the Gordon River and Naples Bay and
they both include land that is within the City. The GRE watershed is the number one priority for
the County with the MGG watershed being number two.




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      Collier County Hazard Mitigation Plan          April 15, 2005



City of Naples Drainage Basin Map:




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       Collier County Hazard Mitigation Plan                                           April 15, 2005



Principle Flood Problem Areas Identification:




Data Sources Basin III
The 1990 Study reviewed flooding compliant files from January 1985 through June 1990.
Various City staff was interviewed and the following flooding problems areas were identified.
   • All of Gulfshore Blvd. within Basin III
   • 13th Avenue South from 4th Street South to 7th Street South
   • Southwest corner of 3rd Avenue South and 6th Street South
   • Intersection of 5th Avenue South and 6th Street South
   • Intersection of 5th Avenue South and Park Street
   • 8th Street South from 3rd Avenue South to North of the Basin III Boundary
   • 9th Street South from 10th Avenue South to 6th Avenue South
   • 10th Street South from 10th Avenue South to North of the Basin III Boundary
   • 10th Avenue South from 9th Street South to Naples Bay
   • Southeast corner of 11th Street South and 8th Avenue South

The 1996 Master Plan identified the following problem areas:
   • 5th Avenue South from 3rd Street South to 7th Street South
   • 9th and 10th Street from 10th Avenue South to 5th Avenue South

In the 2000 interviews, City staff noted problems in the following areas
    • 5th Avenue South from the Eastern Basin Boundary to 3rd Street south
    • Southeast corner of 11th Street South and 8th Avenue South as well as most of the areas
        bordering the Naples Bay. This is a tidal problem; extreme high tides are sometimes
        higher than the existing ground.
    • Gulf Shore Boulevard from 2nd South to 12th Avenue South



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         Collier County Hazard Mitigation Plan                                          April 15, 2005



    • 13th avenue South from 4th Street South to 7th Street South
 Figure 3-1 illustrates the location of the reported flooding problem areas within Basin III.
 The lines indicate areas with widespread problems. The dots (boxes) represent areas with
 more localized flooding problems.

 Basin VI Assessment Report
 In the 1981 Study, observed street flooding locations in Basin VI as follows:
     • 5th Avenue north, from 19th Street North to 11th Street North
     • 10th Street North, from 3rd Avenue south to 5th Avenue South
     • Intersection of US-41 and Central Avenue. City staff noted that chronic flooding
          problems continue to affect this area.
 In 1990 various staff members were interviewed and the following flooding problem areas were
 identified within basin VI:
     • 10th Street. This includes the entire length of 10th street within the basin boundary, a
          substantial increase over what was reported in the 1981 Citywide Drainage Study. This
          continues to be a high priority flooding problem area.
     • Central Avenue, from 7th Street to 10th Street.
     • 8th Street, from 3rd Avenue south to 2nd Avenue North
 In 1998, staff members were interviewed and the following problem areas were identified:
     • Intersection of US-41 and 5th Avenue South
     • Central Avenue, from US-41 to Goodlette-Frank Road. This area extends further east
          than was previously reported in the 1990 Study.
     • 10th Street from 5th Avenue North to 5th Avenue South.

 Figure 3-1 shows the flooding problem areas.

 Additional Flood Prone areas were identified by staff:
   • Gordon Drive from Bay Road to 32 Avenue South and surrounding areas.
   • Lantern Lane from Kingstown Drive,
   • 13th Ave South from 4th Street to 7th Street,
   • 10th Avenue South from 9th Street South to Naples Bay,
   • 10th Street from 10th Avenue south to 7th Avenue North, including the intersection,
   • 10th Street from 7th Avenue North to Fleischmann Blvd. and East,
   • Central Avenue from 7th Street to 10th street,
   • 8th Street from 3rd Avenue South to 2nd Ave. North
   • 13th Street from 12th Avenue North including 14th Avenue north,
   • 15th Avenue North
   • Intersection of Crayton Road and Spyglass Lane and surrounding areas,
   • Gulfshore Blvd. from 1900 to 400 Mooring Line Drive and surrounding areas,
   • Intersection of Rivera Drive and US-41 to Goodlette-Frank Road,
   • Northeast intersection of Goodlette-Frank Road and Golden Gate Parkway.

 The areas identified by City staff have chronic drainage problems and are predominately located
along major roadways (10th Street, Central avenue, Goodlette-Frank Road, Golden Gate
Parkway, Gulfshore Blvd. and US-41).

Figure 4-1 shows additional flood prone areas.




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M.     CITY OF MARCO ISLAND DRAINAGE SYSTEM

The City of Marco Island Stormwater Drainage System generally directs runoff into man-made
and natural water bodies, which are in turn connected to natural bays, and tidal water bodies.
The existing drainage system relies on open swales that discharge into catch basins with
subsequent short runs (less than 170 feet) of small diameter pipe (15 to 30 inches) that outfall
directly to interior waterways.
In November of 1999, the Marco Island Drainage Atlas was produced. Because stormwater
runoff discharges directly or through short runs of pipe into man-made and natural water bodies
there are no identifiable major drainage basins.
To provide a thorough analysis of the existing system and conditions, a Drainage Report was
commissioned and completed in March 2000.
Through field observations and computer modeling existing conditions with their resultant
problems were identified and solutions produced.

                                 Stormwater Drainage Existing Conditions

     EXISTING DRAINAGE                                 RESULTED                 SOLUTIONS TO
         CONDITIONS                                   PROBLEMS                   PROBLEMS
                                                 Pavement Settlement,
  Deteriorated Outfall Pipes                                               Replace Deteriorated Pipe
                                                        Sinkholes
                                                Inhibit Maintenance and    Replace/cut down drainage
 Raised Concrete Drainage
                                               Inspection, and Roadside    structures; arterial/collector
        Structures
                                                       obstructions              roads are priority
                                                                           System inspection with de-
     Blocked Swales, Non-                         Nuisance Ponding
                                                                          silting and clean out, replace
      connected Outfalls
                                                                                 deteriorated pipes
                                                                          Eliminate swale intersection,
      Swale Inspections                           Nuisance Ponding
                                                                          provide additional inlets and
                                                                                        pipes
                                               Nuisance Ponding, Dam         Re-grade swales; create
         Swale Drive
                                                       Effect                    additional outfalls

Marco Island has maintenance and capital improvement programs in place that address the
above deficiencies. Over the next few years, these programs will correct the drainage problems
and create a system free of nuisance ponding.

The direct drainage of stormwater runoff into associated canals and adjacent waterways could
impact water quality, fishing, and recreational uses. Through the “Conservation And
Recreational Land” initiative (CARL program of FDEP), lands are being acquired to preserve
access, recreational value, and stormwater filtration for these fragile environments.

A Marco Island Drainage Map has been included, showing the infrastructure of the system with
associated catch basins and drainage piping.




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                                     Regulations and Programs
   1.      Land Development Code: The City of Marco Island originally adopted the Collier
           County Land Development Code on November 6, 2000. Following this, the City
           adopted a new Land Development Code. The Code facilitates adequate and proficient
           provisions of drainage systems and, at the same time, protects, conserves, and
           appropriately utilizes natural resources within the City’s incorporated limits.
   2.      South Florida Water Management District (SFWMD): South Florida Water
           Management District’s manual “Basis of Review” provides the rules and regulations
           required for water quantity and quality discharge.
   3.      Florida Department of Environmental Protection (FDEP): The FDEP is involved
           with standalone marina and multi-family projects. Their regulations are found in the
           above-mentioned Basis of Review manual.
   4.      Florida Department of Transportation (FDOT): FDOT has jurisdiction over S.R. 951
           and any drainage issues that occur within its right-of-way. FDOT has developed a
           Drainage Connection Permitting Manual for drainage projects occurring within any
           FDOT right-of-way.
   5.      Collier County: The City of Marco Island has adopted the Collier County Land
           Development Code. The County’s Stormwater Ordinance *90-10 should be consulted
           whenever changes are proposed to the Land Development Code (LDC) for the design
           and construction of stormwater drainage facilities.
   6.      United States Corps of Engineers (Corps): The Corps does not typically regulate
           stormwater discharges. The Corps may need to be contacted and permit applications
           pursued should construction of drainage facilities require fill in federal jurisdictional
           wetlands.

                                                Conclusion
The City of Marco Island’s stormwater drainage system is a dynamic program of maintenance
and capital improvements. The system’s objectives are to create a viable comprehensible
drainage system capable of eliminating stormwater normal and event related incidents.

N. REFERENCES

An Environmental Evaluation of the Gordon River of Naples, Florida, and the Impact of
     Developmental Plans, Howard T. Odum, Charles Littlejohn, and Wayne C. Huber,
     September 1972.

An Initial Report on the Augmentation of Surficial Flow Through the Fakahatchee Strand, Collier
      County, Florida, William J. McElroy (Florida Department of Environmental Regulation) and
      Captain K. C. Alvarez (Florida Department of Natural Resources), Sept., 1975.

Belle Meade-Royal Palm Hammock Water Management Plan, CH2M Hill, July, 1982.

Cocohatachee Canal Salinity Control Structure Hydrologic Report,Collier County, Florida, Gee
     and Jensen Engineers-Architects-Planners, Inc., October, 1981.

Collier County Stormwater Management Program, Phase I -- Master Plan, Post, Buckley, Schuh
      & Jernigan, Inc., 1990.

D-2 Canal Drainage System Study, Hole, Montes and Associates, September, 1984.




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Exploratory Drainage Study of Eastern Collier County, Smally, Wellford, and Nalven, June,
     1962.

Final Report on the Augmentation of Surficial Flow Through the Fakahatchee Strand, Collier
      County, Florida, William J. McElroy (Florida Department of Environmental Regulation) and
      Captain K. C. Alvarez (Florida Department of Natural Resources), Sept. 1975.

Golden Gate Estates, Draft Feasibility Report, U.S. Army Corps of Engineers, February 1986.

Golden Gate Estates, Reconnaissance Report, U.S. Army Corps of Engineers, April, 1980.

Golden Gate Water Management Study, Johnson Engineering, Inc. December 1981.

Gordon River Watershed Study, CH2M Hill, February 1980.

Groundwater Resources of the Cocohatchee Watershed, Collier County, Florida, Missimer and
     Associates, Inc., July, 1984.

Hydrogeologic Information on the Water-Table Aquifer Adjacent to the Proposed Control
     Structure on the Cocohatchee Canal, Collier County, Florida, Missimer and Associates,
     Inc., July, 1984.

Hydrologic Effects of Storm of Sept. 1-3, 1983, in Golden Gate City, Collier County, Florida,
     Johnson Engineering, Inc., Sept., 1983.

Hydrologic Study of the G.A.C. Canal Network, Collier County, Florida, Black, Crow and
     Eidsness, Inc., October, 1974.

Hydrological Effects of the Proposed Gordon River Canal, Naples, Florida, Bertran W. Morrow
     and John A Stevens (University of Miami), 1971.

Hydrological Study of the Effects of the Proposed Gordon River Canal, Naples, Florida, R.
     David G. Pyne and J. I. Garcia-Bengochea (Black, Crow and Eidsness, Inc.), 1971.

Hydrology of Western Collier County, Florida, Jack McCoy (U.S. Geological Survey), 1972.

Lely Outfall Surface Water Management System, CH2M Hill, Dec., 1979.

Master Plan for Water Management District No. 6, Collier County, Florida, Black, Crow and
     Eidsness, Inc., February, 1974.

Master Plan Update for Water Management District No. 6, Wilson, Miller, Barton, Soll, and
     Peek, Inc., October, 1985.

Master Plan, Water Management District No. 7 Including the Cocohatchee and Gordon River
     Basins, Collier County, Florida, Black, Crow and Eidsness, Inc., March, 1975.

Natural Resources of Collier County, Florida, Technical Report 84-3, Coastal Estuarine
     Resources, Collier County Natural Resources Management Department, 1984.




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Natural Resources of Collier County, Florida, Technical Report 84-4, Coastal Zone
     Management Units: Data Inventory and Analysis, Collier County Natural Resources
     Management Department, 1984.

Phase 1, Golden Gate Estates Redevelopment Study, Collier County, Florida, Golden Gate
     Estates Study Committee, June, 1976.

Preliminary Study, Water Management in North Naples and East Naples Area, County of
      Collier, Florida, Smally, Wellford and Nalven, March, 1961.

Proposed Boundary for the Big Cypress Basin, South Florida Water Management District,
     Black, Crow and Eidsness, Inc., Sept., 1976.

Proposed Interim Modifications, Golden Gate Estates Canal System, CH2M Hill, November,
     1978.

Proposed Lely Canal Water Control Structure, Collier County, Florida, CH2M Hill, December,
     1978.

Regional Water Resources Study, Big Cypress Basin Program No. 2201, Gee and Jensen
     Engineers-Architects-Planners, Inc., Nov., 1980.

Report on Proposed Drainage and Road Improvements in Southeastern Collier County, Florida,
     Smally, Wellford, and Nalven, Nov., 1962.

Report on Water Management in Collier County, Florida, Smally, Wellford, and Nalven, May,
     1961.

Surface Water Conservation Study, C-31/Golden Gate Canal System, Johnson Engineering,
     Inc., May, 1986.

The Big Cypress Watershed, A Report to the Secretary of the Interior, Everglades-Jetport
     Advisory Board, April 19, 1971.

The Effect of the Faka Union Canal System on Water Levels in the Fakahatchee Strand, Collier
     County, Florida, U.S. Geological Survey Water Resources Investigations 77-61,
     September, 1977.

Water Management in Western Collier County and a Proposed Water Conservation District,
     Smally, Wellford, and Nalven, June, 1963.

Water Resources Data and Related Technical Information to Assist Local Government Planning
     in Collier County, South Florida Water Management District, February 1, 1987.

U.S.G.S. Water Resources Data--Florida, Water Year 1980, Vol. 2A, U.S. Geological Survey,
     October 1981.

U.S.G.S. Water Resources Data--Florida, Water Year 1981, Vol. 2A, U.S. Geological Survey,
     October 1982.




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U.S.G.S. Water Resources Data--Florida, Water Year 1983, Vol. 2A, U.S. Geological Survey,
     October 1984.

U.S.G.S. Water Resources Data--Florida, Water Year 1984, Vol. 2A, U.S. Geological Survey,
     July 1, 1986.

U.S.G.S. Water Resources Data--Florida, Water Year 1985, Vol. 2A, U.S. Geological Survey,
     May 27, 1987.

Watershed Analysis Henderson Creek Basin, (Draft), Johnson Engineering, Inc., May, 1990.

City of Naples References:
City of Naples Utility Department
City of Naples Major Basin and Sub-Basin Identification by Camp, Dresser and McGee

City of Marco Island References:
City of Marco Island Community Development Department
City of Marco Island Utility Department
Marco Island Drainage Atlas produced by RWA, Inc. Civil Engineers Developmental and
Environmental Consultants




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O. COLLIER COUNTY DRAINAGE BASIN MAP

The following map provides a color-block view of the various drainage basins within Collier
County. This information is taken from the Collier County Geographical Information System as
a part of the Stormwater layering system. Information about this map can be obtained by
contacting the Collier County Stormwater Management Department.




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7.2.2   COLLIER COUNTY’S FLOODPLAINS

The Flood Insurance Rate Map (FIRM) for Collier County identifies the base floodplain identified
as flood zones beginning with the letters “A” or “V”. The base floodplain is also known as the
Special Flood Hazard Area (SFHA). However, for Collier County, the FIRM currently only
provides an analysis for coastal flooding. There is an ongoing Flood Insurance Study being
performed by Collier County and the City of Naples to produce information for a new FIRM that
analyzes both coastal flooding and inland flooding. This Flood Insurance Study will utilize the
latest LIDAR topographic mapping and it is expected to be completed in 2005.

With the extremely flat topography in Collier County, flooding tends to be shallow and slow
moving. During typical intense rainfall events certain areas within the County have been
observed to experience street and yard flooding. The “Collier County Areas of Poor Drainage”
map included in this section provides approximate “bubbles” of repeated urban flooding areas
that are not necessarily within the SFHA. The causes of the flooding include, but are not
necessarily limited to, older designs with lesser standards, inadequate or total lack of
maintenance of stormwater system facilities, and lack of understanding regarding the overall
drainage basin. Outside of the urban area, observed flooding typically occurs in shallow natural
depression areas that years ago functioned as sheetflow areas before the construction of
streets, ditches, and canals.

Current development standards requiring a minimum floor elevation equal to the base flood
elevation from the FIRM, the 100-year zero discharge design elevation for a development, or
18” above the road grade, whichever is higher, generally function to prevent structure flooding.
However, older structures built to lower standards and development on formerly vacant land can
impact the severity of structure flooding.




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                          Collier County Hazard Mitigation Plan                                                              April 15, 2005




7.2.3                     TROPICAL CYCLONES

Please refer to Appendix 1 of Annex A in this Collier County Hazard Mitigation Plan for a
thorough discussion on the effects of tropical cyclones within Collier County.

7.2.4                     SEVERE STORMS

Please refer to Appendix 2 of Annex A in this Collier County Hazard Mitigation Plan for a
discussion on the effects of severe storms within Collier County. A discussion on the effects of
tornadoes within Collier County can be found in Appendix 4 of Annex A. Collier County’s
location in a sub-tropical climate greatly reduces the potential for severe storms that are not
associated with tropical cyclones.

7.2.5                     FLOODING

Flooding in Collier County is a factor of the amount and timing of rainfall and the tide cycle
elevation. The following bar chart illustrates the average annual monthly rainfall totals for
coastal Collier County. As can be readily seen, Collier County experiences a summer “wet”
season and a winter “dry” season. These “average” monthly totals are from measured rainfall
extending back to 1940 and represent some fairly wide ranges from very dry years to very wet
years.


                                                             Collier County Average Annual Rainfall


                        10.00
                                                                                                       9.00
                         9.00                                                   8.44
                                                                                       8.24    8.24
                         8.00

                         7.00
   Inches of Rainfall




                         6.00

                         5.00
                                                                         3.87                                  3.78
                         4.00

                         3.00
                                                     2.20         2.11
                                  1.89     1.97
                         2.00                                                                                         1.73
                                                                                                                             1.42

                         1.00

                         0.00
                                  Jan.      Feb.     Mar.         Apr.   May    June    July    Aug.   Sept.   Oct.   Nov.   Dec.
                                                                                   Month


The same amount of rainfall occurring in March would not have the same flooding effect as if it
occurred in September. During the “dry” season the water table elevation typically drops to
several feet below natural ground elevations. This creates a large storage volume in the soil,
lakes, ditches and swales. However during the “wet” season the water table elevation is often
very near the natural ground surface, lakes are filled, and ditches are flowing. The rainfall



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added to this “wet” season condition creates much more stormwater runoff that must be handled
by the stormwater system facilities, creeks, rivers, and natural flowways.

The elevation of the tide cycle can have a substantial effect on the potential for flooding. High
tide elevations of +2.0’ NGVD can greatly restrict the discharge capacity of stormwater systems
discharging into the coastal brackish waters. Some developed areas of Collier County have
ground surface elevations of approximately +3’ NGVD. Ditches and storm drains backfill with
brackish water from the high tide stages, and thus have greatly reduced discharge capacities.

While each 24-hour duration rainfall event is different, during a wet “wet” season (meaning an
above average wet season rainfall amount) a 3 to 4 inch event will typically produce only limited
yard and street flooding; a 5 to 6 inch event will typically produce moderate to substantial yard,
street and major roadway flooding with an occasional structure flooding; and a 7 inch or more
event will typically produce extensive yard, street and major roadway flooding with increased
probability of structure flooding.

As was previously stated in the discussion on floodplains, the extremely flat topography creates
shallow flooding conditions with slow moving waters. The fine-grained sandy soils in Collier
County are readily impacted by erosion and scour at flow velocities above 2 feet/second. With a
few occasional exceptions around some culverts and storm drains discharging into canals or
areas where shallow berms are overtopped, the drainage systems do not exhibit extensive
scour or erosion. To the general observer, it appears as though the water is simply standing in
the swales and ditches and not flowing.

The depth and duration of flooding varies with each intense rainfall event.

Please refer to Appendix 5 of Annex A in this Collier County Hazard Mitigation Plan for an
additional discussion on the effects of flooding within Collier County.

7.2.6   TSUNAMIS

An analysis of the potential destruction to Collier County from tsunamis is discussed in
Appendix 11 of Section 2.0 Hazard Identification and Vulnerability Analysis of the Hazard
Mitigation Plan.

7.2.7   REPETITIVE LOSSES

Within the political boundaries of Collier County, which includes the incorporated municipalities
of Naples, Marco Island and Everglades City, there were thirty-seven (37) properties identified
as repetitive loss properties and two (2) properties listed as former repetitive loss properties that
had been mitigated as of February 29, 2004. Of these 37 properties, the owners have
demolished two and one address could not be documented as ever being valid. This
information was provided to FEMA in October 2004 on the AW-501 RL Update Worksheets.
The jurisdictional responsibility for the remaining 34 repetitive loss properties is as follows:

Collier County                                  25
City of Naples                                   7
City of Marco Island                             1
City of Everglades                               1




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A map showing the approximate locations of the repetitive loss properties is included as
Attachment 3 to Appendix 5 (Flooding) of Section 2.0 Hazard Identification and Vulnerability
Analysis of the Hazard Mitigation Plan.

Analyzing the Repetitive Loss Property Claims Payments provides the following information:
   Total Number of Paid Claims                95
   Total Building Payments              $1,176,873.15
   Total Contents Payments                $192,136.22
   Total of Building and Contents       $1,369,009.37

Of the payments made, the largest payments came from two claims to a house at Morgan
Beach/Cape Romano. These amounted to a total of $500,000 but recent observations of the
house do not indicate that the funds were used to restore the house to a habitable condition. A
total of $57,893.94 was paid in claims to structures that have now either been mitigated,
demolished, or the address determined not to exist.

Generally speaking, the locations of the repetitive loss properties are in older developed
portions of the community. Two areas, Naples Park and the Gateway triangle, contain 15 of the
repetitive loss properties. The Naples Park area has been evaluated for drainage
improvements and a recommended plan developed. However the majority of residents have
repeatedly expressed their opposition to construction of the improvements due to the cost and
method of proposed payment through a special taxing district. The Gateway Triangle area is
currently being evaluated and a stormwater management system design being developed that
will provide improved flood protection and improved water quality discharge.

7.3    EVALUATE THE PROBLEM

7.3.1 SUMMARY OF EACH HAZARD IDENTIFIED

Section 2.1.1 of the Hazard Mitigation Plan identified Flooding and each of the other hazards
that were studied. Appendix 5 specifically reviewed Flooding Hazards.

7.3.2 DESCRIPTION OF THE IMPACT OF THE HAZARD TO LIFE, SAFETY, AND HEALTH

Section 2.6 Type of Losses/Damages Anticipated in the Hazard Mitigation Plan, and Appendix 5
describes the impact of flood hazard to life, safety, and health.

7.3.3 IMPACT THE HAZARD WILL HAVE ON CRITICAL FACILITIES

Section 2.5 Essential Facilities of the Hazard Mitigation Plan identify five categories of buildings
and facilities that are based on their loss potential. Annex B identifies the location of these
Essential Facilities in a series of four maps.

7.3.4 NUMBER AND TYPES OF BUILDINGS SUBJECT TO HAZARDS

Potentially every building within Collier County could be affected by flood hazards from tropical
cyclones, severe storms, and tsunamis. Areas along the Gulf Coast, which are identified as a
Special Flood Hazard Area (SFHA) are at greatest risk. Appendix 5 of Annex A in the Hazard
Mitigation Plan illustrates the scope of Coastal Flooding.




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An assessment of the number and type of building uses subject to flooding hazards was
undertaken using the County’s GIS and information from the Collier County Property Appraiser
database as of November 2004. Three zones were considered from the information entered
into the database. Acreage numbers were rounded to the nearest whole acre. For each zone
tabular data plus a map have been provided below.

Coastal High Hazard Zone:
    Total Land Value                           $13,011,976,199
    Total Improvements Value                    $5,389,419,838
    Total Summed Value                         $18,401,396,037
    Total Taxable Value                        $13,366,007,207

     Total Number of Parcels                              35,768
     Total Number of Parcels w/Structures                 20,286

     Total Acres                                         228,362
     Total Acres of Improved Land                         20,556




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      Collier County Hazard Mitigation Plan                      April 15, 2005




FEMA VE Zone
    Total Land Value                            $845,682,455
    Total Improvements Value                     $233,790,664
    Total Summed Value                         $1,079,473,119
    Total Taxable Value                          $682,794,214

    Total Number of Parcels                              1,581
    Total Number of Parcels w/Structures                   462

    Total Acres                                         32,953
    Total Acres of Improved Land                           668




FEMA AE Zone
    Total Land Value                          $13,580,146,205
    Total Improvements Value                   $7,333,716,671
    Total Summed Value                        $20,913,862,876
    Total Taxable Value                       $15,535,895,932




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     Total Number of Parcels                           49,407
     Total Number of Parcels w/Structures              28,986

     Total Acres                                      284,129
     Total Acres of Improved Land                      34,589




7.3.5 NATURAL AND BENEFICIAL FUNCTIONS

Collier County is situated in a unique, sensitive and intensely interactive physical environment.
Natural Resources are abundant: a subtropical climate with annual wet and dry seasons:
enormous groundwater productivity; vast wetland areas; large ranges of habitat with diverse and
unique flora and fauna, including many species that are Federally and/ or State listed,
warranting special protection: extensive and highly productive estuarine systems; and, many
miles of sandy beach. In addition to their habitat value, these natural resources perform
functions that are vital to the health, safety and welfare of the human population of the County,
and serve as a powerful magnet to attract and retain visitors and residents. Therefore,
protection and management of natural resources for long-term viability is essential to support
the human population, ensure a high quality of life, and facilitate economic development.




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7.3.6 DEVELOPMENT, REDEVELOPMENT, AND POPULATION TRENDS

Section 2.3 Land Use Patterns of the Hazard Mitigation Plan describes the development and
redevelopment patterns in Collier County. Section 2.4 Demographics of the Hazard Mitigation
Plan provides a summary of the population trends.

7.3.7 SUMMARY OF THE IMPACTS ON THE COMMUNITY

Section 2.7 Risk Summary of the Hazard Mitigation Plan provides a summary of the flood and
other hazards studied, as well as, the anticipated impacts.

7.4     SET GOALS

The Local Mitigation Strategy Working Group developed goals and objectives based on the
County’s Comprehensive Plan and codes. These goals and objectives are identified in Section
3.0 Local Mitigation Strategy Goals and Objectives of the Hazard Mitigation Plan.

7.5     REVIEW MITIGATION STRATEGIES

7.5.1   PREVENTATIVE ACTIONS

Maintenance of the existing storm water management system will be the primary preventative
action for the County. The cooperation of Federal and State Conservation Agencies, the South
Florida Water Management District, County and Municipalities, and Private Property Home
Associations will each be encouraged to facilitate a scheduled maintenance of their storm water
management facilities.

7.5.2   PROPERTY PROTECTION ACTIVITIES

Property protection activities will be incorporated through: Building Codes, Land Development
Code Standards, Growth Management Plan, and Flood Plain Management Ordinance of the
county and the municipalities. The Flood Warning Program, as identified in Collier County
Comprehensive Emergency Management Plan’s Annex E, will be the foundation for public
awareness and emergency evacuation procedures for flood hazards.

7.5.3   NATURAL RESOURCE PROTECTION ACTIVITIES

As mandated through National and State regulations, the county will provide natural resource
protection activities. The Growth Management Plan’s Goals and Objectives particularly, the
Conservation and Coastal Management Element identify specific environmental resource
protection activities. In the Land Development Code, in Chapter 3 identify specifications, which
need to be addressed for new development within the unincorporated area of Collier County.

7.5.4   EMERGENCY SERVICES ACTIVITIES

As identified previously, the Collier County Flood Warning Program –will be the foundation for
public awareness and emergency evacuation procedures for flood hazards. The All Hazards
Guide – 2005 Edition is standard public information tool, which the county publishes and
distributes annually.

7.5.5   STRUCTURAL PROJECTS


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The proposed structural projects to mitigate the flood hazards within the county have been
provided in the Hazard Mitigation Plan - Annex G. This plan is reviewed annually, and new
structural project can be submitted and evaluated annually, based upon the procedures
established in Section 4 of the Hazard Mitigation Plan.

7.5.6   PUBLIC INFORMATION ACTIVITIES

An integral component of a quality Flood Plain Management Plan is the participation of the
general public. Section 1, and Annex E of the Hazard Mitigation Plan describes the process
that was provided to incorporate public participation in the development of the Flood Plain
Management Plan and the Hazard Mitigation Plan. These plans call for the continued
participation by the general public. The publication and distribution of over 10,000 copies of the
All Hazard Guide has been an out reach effort by the county since 2000. Flood Hazard
information is posted on the county’s web site and is also mailed out to over 1,000 property
owners that have property in the Special Flood Hazard Area. In times of emergencies, the City
of Naples, the City of Marco Island, and the City of Everglades all participate in the County’s
Flood Warning System (identified in Annex E of the Collier County Comprehensive Emergency
Management Plan) which utilizes the broadcasting services of WNOG 1270 AM and 93.5 FM
and other local radio and television stations. Warnings from the National Weather Service, the
National Hurricane Center and Collier County Emergency Management can be heard on these
stations. Additionally, police and fire officials will also notify residents of evacuations.

7.6     MITIGATION STRATEGIES

7.6.1   ACTION PLAN

The Action Plan will consist of the implementation of the adopted Collier County Hazard
Mitigation Plan. The Action Plan provides for the participation of a Local Mitigation Study
(LMS) working group, and the use of a Community Rating Systems Subcommittee to identify the
various Hazards and Plans for the Mitigation of those hazards. A listing of “Goals and
Objectives” from the Growth Management Plan that are related to Hazard Mitigation have been
provided. A procedure for prioritizing Hazard Mitigation Initiatives has been provided. A list of
current proposed mitigation funding sources has been prepared. A plan for maintaining the
Hazard Mitigation Plan has been provided.

7.6.2 POST-DISASTER MITIGATION POLICIES AND PROCEDURES

A Post-Disaster Mitigation Policies and Procedures outline has been prepared and is identified
as the 2004 Collier County Flood Warning Program and Comprehensive Emergency
Management Plan.

7.7     ADOPT THE PLAN

The adoption of the Flood Hazard Mitigation Plan will be in conjunction with the adoption of the
Collier County Hazard Mitigation Plan. Annex D of the Hazard Mitigation Plan identifies that
each of the three participating Collier County governments will be adopting the updated Collier
County Hazard Mitigation Plan following the approval of the revised document by the Florida
Division of Emergency Management and Federal Emergency Management Agency.




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7.8    IMPLEMENTATION, EVALUATION, REVIEW

Section 6.0 Revision/Update Procedures and Incorporation of Hazard Mitigation plan into Local
Government Comprehensive Plans provides format by which the Hazard Mitigation Plan, as well
as the Flood Hazard Plan will be monitored.




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