HomeMy WebLinkAboutDocumentation_Environmental Advisory Committee_Tab 01_1/12/2022Agenda Item #1.
Environmental Advisory Committee (EAC)
STAFF MEMO
Meeting: Environmental Advisory Committee (EAC) - Jan 12 2022
Staff Contact: Matthew Hammond, Utilities Department: Utilities
Director
Draft Stormwater Manual Presentation
SUMMARY:
This document and any attachments may be reproduced upon request in an alternative format by completing
our Accessibility Feedback Form, sending an e-mail to the Village Clerk or calling 561-768-0443.
2022.01.12.EAC Stormwater Manual Presentation2
2022.01.12.EAC Stormwater Manual Presentation.ada
DRAFT. Residential Stormwater Guidelines.ada
DRAFT. Stormwater Manual.ada
Page 4 of 95
Agenda Item #1.
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'W66MItem #1.
in the Village of Tequesta
December 2021
A. Stormwater Management — an important element of the site plan ........ 2
B. Guidelines to prepare your site plan ...................................................... 3
C. Guidelines to address stormwater management in your site plan........... 4
D. Sample site plans.................................................................................. 7
E. Guidelines for expansion of existing homes ............................................ 12
Page 13 of 95
Agenda Item #1.
WHY all the fuss, you ask? Here's why...
The Village of Tequesta enjoys a waterfront environment between the Loxahatchee River and Indian River.
Most of the year, Tequesta enjoys a sunny, near -tropical climate; but there comes a rainy season, from May through
October. During the rainy months, frequent thunderstorms can last from a few minutes to a few days.
Heavy seasonal rains cause stormwater to flow from ("run off") commercial and residential rooftops, yards, and
streets. This stormwater normally collects in the streets and works its way toward the nearest drainage inlet and
waterway. Although street flooding is a temporary nuisance, the pollutants carried in the stormwater create a less
visible but longer -lasting effect. These pollutants include automobile oil and grease, lawn fertilizers and pesticides, a
variety of chemicals from commercial/industrial areas, and silt and fl Aig, debris from highways.
Continued pollution of Florida's coastal area has severely degraded one o ur mostNable resources, our
waterways. Pollution also has negatively affected the quality and claritur waters. It has reduced our fish and
wildlife populations.
Stormwater running off into the streets also wastes a val
months of November through April.
The Village of Tequesta has adopted a comprehe
le resource. After the rainy season comes the dry
ent plan that establishes specific goals for
sustainable growth and development without compromising the biodiversity and intrinsic value of its natural
resources. To achieve these goals and to begin reversing the current negative trends, we must significantly reduce
the potential pollution from new construction.
Our current Stormwater Management Practices Manual establishes guidelines for the safe management and
disposal of stormwater runoff from developed areas. The Stormwater Management Practices Manual is applicable to
all developments and requires that all applications for building permits must contain a stormwater management
plan.
The guidelines and recommendations in this Residential Stormwater Guidelines Brochure are designed to help you
address stormwater management in the site plan for your single-family residential lot. Sample engineering
calculations supporting the guidelines of the Brochure are available in the current version of the Village's
Stormwater Management Practices Manual.
Page 14 of 95
Agenda Item #1.
OKAY, what must I do to prepare a site plan for my single-family or duplex home?
To prepare a site plan, you must assess the existing site conditions, evaluate the proposed improvements, and make
provisions for stormwater management. This process begins with collecting site -specific data by performing a lot
survey. The lot survey is then used as a base to locate the proposed improvements and grade the lot to control
stormwater runoff. Grading is reshaping or sloping your land in a way that surface drainage from runoff is directed
away from the buildings and is controlled in a manner that eliminates or minimizes the impact on adjacent
properties and public rights -of -way. The following steps detail the data
information to be provided in the site plan.
STEP ONE — SURVEY DRAWING
J
Obtain a boundary survey and topographic information (from survey or
r the lot survey and the
light detecting and radar
[LiDAR] data) for your lot. The survey must be performed by a professional land surveyor licensed to practice in
Florida. The survey drawing must provide the followin ation:`
a. Legal description of lot.
b. Property line dimensions, bearings, and/or angles.
c. Location of existing improvements, to include adja t properties, street, and waterway (if any).
d. Three cross -sections, showing elevations from the street, across lot lines, and center of the property (LiDAR-
based elevations may be used if available).
e. Location and identification of trees.
f. Location sketch and identification of a nearby Mile Marker if run-off is directed toward the Indian River or
Loxahatchee River.
g. Drawing scale (1-inch = 10 feet, recommended) and a north arrow.
STEP TWO — SITE PLAN
Prepare a site plan showing the proposed improvements, utilities, landscaping, and site grading. The site plan, which
must meet the guidelines described later in this Brochure, should be prepared at a recommended scale of 1 inch =
10 feet and provide the following information:
a. Locations, dimensions, and types of construction materials of the building, roof, patio, screened porch, deck,
shed, pool, and driveway.
b. Proposed site grading showing existing and proposed elevations and/or contours (include proposed first
floor and garage elevations and top of foundation elevation).
c. Proposed drainage directions and areas draining to each retention system. Site grading must drain toward a
retention system. Your run-off must not impact your neighbor's property.
d. Locations, dimensions, and types of materials to be used in landscaping features, such as planters, walks,
privacy walls, fences, trees, and shrubs.
e. A cross-section (elevation view) across the center of the lot showing proposed improvements and site
grading.
Page 15 of 95
Agenda Item I,A,j2AFT
C. Guidelines to address stormwater management in your site plan
HOW do I address stormwater management in my site plan?
The Village of Tequesta's waterfronts are beautiful and ecologically sensitive to pollutants, many of which are
generated by stormwater runoff. The Village's goals are for sustainable growth and development without
compromising the biodiversity and intrinsic value of its natural resources and meeting state water -quality standards.
To achieve these objectives, the Village requires your new home or new extension to meet the following design and
construction guidelines:
• Preserve Roadside Swales (Plate 2)
1. Maintain the pervious cover of swales.
2. Preserve existing swale elevations.
• Reduce Lot Fill (Plate 2)
1. Carefully consider the need to import any fill for the lot.
• Flood Protection (Plate 3)
1. Elevate the finished flood floor above the Federal Eme k
gement Agency Rase Flood Elevation.
• Reduce Impervious Surfaces
1. Use pervious materials, such as gravel, pervious avers otive grasses, grass -covered porous
pavement, and wood for the construction of o anping improvements. Florida -Friendly
Landscaping'"" is encouraged.
2. Do not place impervious layers, such as roofing p
• Conserve Water (Plates 4 and 5)
1. Use cisterns to collect roof runof recy for no
2. Use native plant materials for la api
• Reduce Direct Discharges to Waterway a 6)
1. Use berms to contain ru dja waterways.
nder paved or landscaped areas.
otable water uses.
2. If your lot has an exi Awbulkheal welW adjacent ground to provide a minimum 6-inch difference
between the finishe and the to f the bulkhead.
• Eliminate Discharges to Adj3W Prope s
Grade site to contain runoTWrgffur lot onto adjacent properties.
• Reduce Discharges to Roadway
Use berms to contain runoff from your lot onto adjacent roadways.
2. Use traffic -rated trench drains across driveways to reduce discharges to the roadway. These trench drains
should be drained to an on -site retention area. Trench drains are not needed where the driveway is below
or at the same elevation as the roadway swale.
• Calculate required retention volume using the following steps:
1. Determine square footage of impervious area on the site that is directly connected to the proposed
retention system (typically this would be an on -site swale). Directly connected would be any area when
stormwater runoff passes over less than 20 feet on pervious area (e.g., grassed or landscaped area) before
entering the on -site retention system. Pervious pavers would not be considered an impervious area.
2. Determine square footage of the impervious area on the site that is unconnected to the proposed retention
system and has to drain over 20 feet or more of pervious area before entering the retention system. An
example of this would be an area of the roof that is drained from a downspout but flows over 20 feet of
landscaped area before reaching the on -site swale.
Calculate the total effective impervious area by summing the directly connected area with half the
unconnected area.
Determine the square footage of the lot.
4
Page 16 of 95
Agenda Mem Iff.
Calculate the ratio of the effective impervious area to the property area.
Use Table 1 to determine the required retention depth. The effective impervious area to the property area
ratio from Step 5 should be rounded to the nearest ratio in Table 1.
Determine the required retention volume (cubic feet) by multiplying the required retention depth in feet
(Step 6) by the property area in square feet (Step 4).
Table 1. Required Retention Depth
Effective Impervious Area to
Property Area Ratio (Step 5)
Required Retention Depth
(feet)
Required Retention Depth
(inches)
1
1 .
•
1
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row, TRAII&M
1
1 .•
If swale(s) are used, they must meet the f1 'V
ollowing criteria:
• Runoff from the site must bd to a swale.
• Swale length must be greater than its width.
• Swale side slope must be 4:1 (horizontal to vertical) or shallower.
• Swale must not disturb any natural areas.
• Swale must be 6 inches or deeper.
• Swales should be vegetated. If a swale is not vegetated, then a 6-inch layer of nutrient sorption soil
amendment media formulated to reduce nutrient loading must be installed directly below the swale.
Specifications and published nutrient reduction test results for the media must be provided for Village
review at the time of permitting. Examples of acceptable media are NutriGoneT" (distributed by EcoSense
International) and Bold and Gold® (distributed by Environmental Conservation Solutions).
5
Page 17 of 95
Agenda Item L,A,j2AFT
If exfiltration trenches or French drains are used on single-family or duplex lots they must meet the following
criteria:
• Minimum of 8 inches of cover.
• Use at least a 4-inch or greater perforated pipe. A prefabricated shallow vault or drainage well may be used.
• Inlets to exfiltration system must include a fabric filter.
• Exfiltration system must not be within 10 feet of a building.
• Exfiltration systems cannot be installed under driveways or other areas that may receive frequent vehicular
traffic, unless designed by a Florida -registered and -licensed professional engineer.
• Bottom of exfiltration system must be more than 12 inches above the wet -season water table. The wet -
season water table can be determined using the US Department of Agriculture (USDA) Web Soil Survey
(https:Hwebsoilsurvey.sc.egov.usda.gov), SoilWeb app available on Android or iPhone devices, or
determined by an appropriate Florida -registered and -licensed professional.
• Volume of an exfiltration trench in cubic feet can be approximated as: V = L x W x (D — 0.96) x 0.4, where
L = length in feet, W = average trench width, and D = average trench depth in feet.
TOP OF PAVEMENT OR FINISHED GRADE
cAGG GA O
FILTER
C O 0 V
FABRIC
0
O
REQUIRED
TRENCH
ERFO D O
TREATMENT
HEIGHT
R 8L0 D
PIPE 0 O
VOLUME
O
(RTV)
O
�0000
ERVOIRD
TRENCH WIDTH RTV RECOVERY BY
T I T T T i SOIL INFILTRATION
SEASONAL HIGH GROUND WATER TABLE (SHGWT)
■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■ ■■■■■■■■■■■■
CONFINING UNIT
TYPICAL "DRY" EXFILTRATION TRENCH X-SECTION
NOT TO SCALE
Generic DRY Exftren X Section m of 12 02 09.dwg
Source: Florida Department of Environmental Protection and Water Management Districts Environmental Resource Permit Stormwater Quality
Applicant's Handbook (March 2010— Draft).
The following diagrams illustrate the above design and construction guidelines and a sample site plan (Plate 7). If you
have other questions, call the Village of Tequesta Building Department at 561-768-0453.
6
Page 18 of 95
Agenda Item #1.
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Agenda Ite°mFb1.
E. Guidelines for expansion of existing homes
WHAT if 1 just want to expand my home?
Any impervious area expansion of existing lot coverage, that is roofs, decks, patios, pools, and pavements, must
provide for the retention of 2.5 inches of runoff from the expansion area. Typically, this retention requirement can
be met by constructing a shallow swale alongside the expansion area. However, other approaches to retaining
stormwater on the site will be considered. The following table shows the proportional stormwater retention storage
required for every 25 square feet of new impervious area:
Provisions for swales must be shown on the site plans submitted with your permit application. Remember, you
should still follow the steps outlined in this Brochure, but you do not need to meet all of the design and construction
criteria required for new homes.
Square feet of new
impervious area
Required cubic feF 3"
4 retention sto ge -.A
MoNWA61M
Lil
11
Page 23 of 95
Agenda Item #1.
FINAL DRAFT
VILLAGE OF TEQUESTA
STORMWATER MANAGEMENT PRACTICES MANUAL
To Be Used With
The Village of Tequesta Code of Ordinance
January 2022
Page 24 of 95
Agenda Item #1.
VILLAGE OF TEQUESTA
STORMWATER MANAGEMENT PRACTICES MANUAL
Prepared
Village o ques
345 Teque ve
Teq Florid 469
by:
Edmunds & Associates, Inc.
-L-
224WalIVach Lakes Boulevard, Suite 300
est Palm Beach, Florida 33409
Jones Edmunds Project No.: 20850-001-01
January 2022
Page 25 of 95
Agenda Item #1.
FINAL DRAFT
TABLE OF CONTENTS
1
2
3
4
INTRODUCTION............................................................................................ 1-1
APPLICABILITY............................................................................................. 2-1
CONTENTS OF A STORMWATER MANAGEMENT PLAN ..................................... 3-1
METHODS OF STORMWATER TREATMENT...................................................... 4-1
4.1 Wet Detention............................................................................................4-2
4.1.1 Definition.............................................................................................4-2
4.1.2 Requirements as Expressed in this Manual...............................................4-2
4.1.3 Method of Achievement.......................................................................4-3
.........4.2 Dry Retention............................................................................4-3
4.2.1 Definition .............................................. ...................................4-3
4.2.2 Requirements as Expressed in this Ma .............. 4-3
4.2.3 Method of Achievement ................ .................................................4-3
4.3 Low -Impact Development or Design.........................................................4-3
4.3.1 Definition .......................... ............................................4-3
4.3.2 Requirements as Expressed in is............................................4-4
4.3.3 Method of Achiever ............................................................4-4
CONTROL STRUCTURE ........ ............................................................. 5-1
5.1 Definition.............................................................................................5-1
5.2 Purpose.... ..........................................................................5-1
5.3 Types of C of Struct s..........................................................................5-1
CRITERIA FOR 4S LE-FAMILY/DUPLEX LOTS ............................................. 6-1
LIST OF FIGURES
Figure 1a Schematic of Basic Wet Detention Stormwater Management Systems ........ 4-1
Figure 1b Schematic of Basic Dry Retention Stormwater Management Systems ......... 4-2
Figure 2 Spreader Swale (Indirect Discharge).....................................................5-2
LIST OF TABLES
Table 1 Required Retention Depth for Single Family/Duplex Lots ..........................6-1
20850-001-01
January 2022
Table of Co tA& 26 of 95
Agenda Item #1.
FINAL DRAFT
APPENDICES
Appendix 1 Stormwater Management Plan Checklist
Appendix 2 Wet -Detention Facilities
Appendix 3 Dry -Retention Facilities
Appendix 4 Control Structures
Appendix 5 Single-Family/Duplex Lots Sample Calculations
Appendix 6 Bibliography
11
20850-001-01 " 27 of 95
January 2022 Table of Cor1tA
Agenda Item #1.
The Village of Tequesta enjoys a waterfront environment between the Loxahatchee River
and Indian River. Due to the importance of its aquatic environment, the Village has adopted
a Stormwater Management Manual to help protect these resources from the harmful effects
of unmanaged stormwater runoff. This manual is based on other municipal stormwater
manuals in Florida.
Stormwater results from a rain event. Runoff is the portion of stormwater that does not
infiltrate into the ground or evaporate and is not intercepted before reaching a stormwater
management system. Stormwater runoff from undeveloped lands usually does not present a
management problem since it is relatively clean with lower volumes and peaks due to
natural filtration and higher infiltration. When natural land is converted to higher intensity
land use, stormwater becomes a problem and should be managed. Soil is often paved over,
and impervious surfaces are created. Impervious surfaces prevent stormwater from
infiltrating into the ground and recharging local surficial aquifers. This reduces uptake by
plants and increases accumulation on the surface. This can create flooding in some areas.
These impervious areas also create an environment where pollutants can accumulate,
degrading the quality of stormwater runoff and r0ndering ifa pollution source. To combat
this, stormwater management practices are implemented in developed areas to help
mitigate potential increases in flood risk ( r quan�,tSnd pollution (water quality).
Stormwater runoff conveys many types of Iuta -he landscape to natural receiving
waters. The quality of stormwater runoff varies with land use. Pollutants in stormwater can
consist of excess nutrients, solid waste, Litter, lead, petroleum products (from automobiles),
chemicals, fertilizers, herbicides applied to lawns, and atmospheric deposition. Higher
nutrient loads are typically generated by residential and industrial land uses and
commercial, mixed urban, and roadw ys generate higher concentrations of metal
contamination. Heavy metals are of�ern because several are toxic to many aquatic plant
and animal species. Motor vehicles�and road surfaces are the main sources of heavy metals
in stormwater runoff. Nutrients and pesticides from lawn fertilizers and atmospheric
deposition can cause algal blooms and similar occurrences if untreated runoff is allowed to
enter surface waters. During a rainfall event, stormwater runoff flows over these surfaces
picking up pollutants and carrying them to surface waters.
Stormwater not only causes adverse environmental impacts but also economic impacts. An
increase in the number of impervious surfaces raises the potential for flooding and property
damage. Stormwater can also lead to reduced fisheries production because of the
degradation of water quality. For these reasons, stormwater management practices have
been implemented throughout Florida and the United States. This manual is designed as a
guide to best management practices (BMPs) for stormwater management in the Village.
A stormwater management practice is one that shapes and improves the quality and
quantity of stormwater runoff being discharged to receiving waters. BMPs for stormwater
are those that meet discharge quantity and quality criteria at a minimal cost (Wanielista and
Yousef, 1985).
20850-001-01 p1-1
January 2022 Introdpcct&e 28 of 95
Agenda Item #1.
FINAL DRAFT
Although this stormwater manual does have general criteria for water quantity and flood
protection, the main purpose is to provide guidelines related to the control of stormwater-
generated pollution and is therefore water -quality based.
The practices and procedures described in this manual are those in common use throughout
Florida and apply to the Village. This manual will be used to review and approve stormwater
management systems permitted by the Village and will be modified as appropriate
technology and regional stormwater rules dictate. The following appendices with more
detailed information have been included with the report:
Appendix 1 — Stormwater Management Plan Checklist
Appendix 2 — Wet -Detention Facilities
Appendix 3 — Dry -Retention Facilities
Appendix 4 — Control Structures
Appendix 5 — Single-Family/Duplex Lots Sample Calculations
Appendix 6 — Bibliography
20850-001-01 p1-2
January 2022 Introdpcct&e 29 of 95
Agenda Item #1.
FINAL DRAFT
2 APPLICABILITY
This manual supplements the Village of Tequesta Code of Ordinances and is incorporated
into the Village Code by Section 66-334. A Stormwater Management Plan will be required
as part of all building permit applications. The definitions used in this manual are consistent
with the Village of Tequesta Code of Ordinances.
20850-001-01 2-1 30 Of 95
January 2022 Apphcp0
Agenda Item #1.
A stormwater management plan is required to be submitted as part of the Village building
permit application pursuant to Section 66-334 of the Village Code. The plan will indicate
how a project design will incorporate the required stormwater treatment criteria. The
elements that may be required as part of a stormwater management plan are listed below.
Appendix 4 is a checklist of these elements that Village staff will use to determine which of
the elements a specific plan should or should not require for each site. Some of these
elements are required for other parts of a Village building permit, but also need to be
considered as part of the stormwater management plan. In these instances, specific criteria
are the same as those already required by the Village and are not discussed further in this
manual.
1. Site Information:
a. Detailed location map.
b. Description of existing vegetative cover includ' wetlan
c. Location and size of preservation or mitiga ' areas (if app ble).
d. Site paving, grading, and drainage plans.
e. Vegetation protection plan.
f. Soils map and percolation test re `
g. Wet -season water -table elevation.
h. Future wet -season water -tab eleva 0-ye r).
i. Description of measures e d du g construction to eliminate adverse off -site
impacts, such as incre d tur it or ation.
j. Recent aerial photograI
in ear that the photograph was taken.
k. Map of drainnnaaem
ies including any off -site areas.
I. Map of floodo
2. Master Stormwat Plan:
a. Location of all existiRWd proposed on -site waterbodies including wetlands.
b. Location of all off -site wetlands, water courses, and waterbodies affected by on -site
drainage patterns.
c. Location and detail of all major control structures and elevations. Preliminary
construction plans may be submitted for conceptual approval.
d. Right-of-way and easement locations for stormwater management systems including
all areas reserved for stormwater management purposes.
e. Location and size of on -site stormwater management facilities.
f. Square footages, acreages, and percentage of property proposed as:
(1) Impervious surface (excluding waterbodies).
(2) Impervious surface (waterbodies).
20850-001-01 p3-12 31 Of 95
January 2022 Contents of a Stormwater Management
Agenda Item #1.
(3) Pervious surface.
(4) Total square footage or acreage of the project site.
g. Proposed grading plan.
h. Treatment volumes and discharge rates (if applicable) for stormwater runoff.
3. Legal and Institutional Information:
a
Entity responsible for operation and maintenance of surface -water management
system.
If the operation and maintenance entity is to be a public body, a letter from the
public body confirming this must be submitted before staff approval. If the entity is a
homeowners' association, documents verifying the exist nce of such organization
and its ability to accept operation and maintenance r nsibility must be submitted
before staff approval.
1`
20850-001-01 p3- 2Age 32 Of 95
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4 METHODS OF STORMWATER TREATMENT
Stormwater treatment facilities are designed to treat stormwater runoff to a level that
results in the pollutant loads discharged after development being less than the pollutant
loads discharged before development (a net improvement) or that results in pollutant loads
being reduced by 95 percent. The volume to be treated depends on the type of stormwater
management facility(ies) used and the land use of the property. The two most used
methods of stormwater treatment are wet detention and dry retention. A detention facility
collects and temporarily stores a treatment volume to provide for treatment through
physical, chemical, or biological processes with subsequent gradual release of the
stormwater to a surface -water system. A retention facility is designed to prevent the
discharge of a given volume; however, it is slowly released from the facility through
infiltration and evapotranspiration. A retention or detention facility built above the
groundwater table is dry. A facility with the bottom below the control elevation is wet.
Figures la and lb conceptually illustrate the differences between each. The wet -season
water table plays an important part in the functioning of retention systems. To ensure that
stormwater facilities continue to function in the future, a stormwater design will need to
include a determination of the wet -season water table and an estimate of the future wet -
season water table. The future wet -season water table will be assumed to increase by the
difference in sea level in the year that the wet -season water table determination was made
and the projected sea level 30 years after permitting. The estimated sea -level rise
projections adopted by the Southeast Florida Climate Change Compact must be used for this
determination.
Figure is
Schematic of
n Stormwater Management Systems
20850-001-01 4-1 33 Of 95
January 2022 Methods of Stormwater TreaprA
Agenda Item #1.
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Figure lb Schematic of Basic Dry Retention Stormwater Management Systems
T.O.B.
Weir Crest Elevation
Treatment
Volume
Storage
Treatment Volume
Recovery by
Infiltration
Peak attenuation
Storage (It requlre_g)_
Seasonal high
groundwater
table elevation
Source: Adapted from the St. Johns River Water Management District Environmental Resource Permit
(ERP) Applicant's Handbook Volume II, 2018.
A newer approach to Stormwater management is called Low -Impact Development or Design
(LID). This approach seeks to replicate a more natural hydrologic function on the landscape
and uses several stormwater management practices to meet the objective stated above.
Some of these practices include pervious pavement, vegetated swales, vegetated filter
strips, bioretention systems, cisterns, and green rooms
A stormwater management system frequent orporates several treatment methods.
Describing all the possible combinations in thi anual is not feasible. The criteria for each
individual type of treatment are detailed to ens that the proper volume of runoff is
treated in an appropriate manner for the land frse. References to guidelines for LID
approaches to stormwater management are also provided.
Appendices 2 throu 'provide the design criteria for each type of management system.
4.1 WET DETENTI
4.1.1 DEFINITION
Wet detention is the collection and temporary storage of stormwater runoff — before
controlled discharge into receiving waters — in a permanently wet impoundment to provide
treatment through physical, chemical, and biological processes with subsequent gradual
controlled release of the stormwater. A wet -detention facility is a basin or pond with a
bottom elevation below the wet -season water table or control elevation.
4.1.2 REQUIREMENTS AS EXPRESSED IN THIS MANUAL
Stormwater designs must demonstrate a net improvement in nutrient loads or a 95-percent
reduction in pollutant loads. This can be demonstrated through methods that are accepted
by the South Florida Water Management District (SFWMD). An example of one of these
methods is using BMP Trains, modeling software that is freely available from the University
of Central Florida Stormwater Management Academy
(https://stars. library.ucf.edu/bmptrains/).
20850-001-01 4-2 34 Of 95
January 2022 Methods of Stormwater TreaprA
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4.1.3 METHOD OF ACHIEVEMENT
Constructed ponds on the site are generally used for wet detention. These ponds must meet
the design criteria in Appendix 2 of this manual. The retention volume can be achieved
using the guidelines in Sections 4.2 and 4.3 of this manual.
4.2 DRY RETENTION
4.2.1 DEFINITION
Dry retention is a stormwater system designed to prevent the discharge of a given volume
of stormwater runoff into surface waters by complete on -site storage of that volume. A dry -
retention facility has a bottom elevation at least 1 foot above the future wet -season water
table and is usually dry. Stormwater is released only during times of heavy rainfall or
flooding.
4.2.2 REQUIREMENTS AS EXPRESSED IN THIS MANUAL
Stormwater designs must demonstrate a net improv
reduction in pollutant loads. This can be demonstra
by SFWMD. An example of one of these methods
that is freely available from the University of Cen
Academy
4.2.3 METHOD OF ACHIEVEMENT
Examples of dry -retention faciliti
bioretention systems) and seep
and exfiltration vaults). Of th
attenuation. The vegetation tak
stormwater runoff. Mo
potential for theme ing the
it in nutrient loads or a 95-percent
rough methods that are accepted
(MP Trains, modeling software
da Stormwater Management
1
Ldein tion systems (e.g., vegetated swales and
( , exfiltration trenches, pervious pavement,
o systems provide better pollution
perc age of the nutrients commonly found in
bind with the soils above the water table and the
kater is reduced.
Seepage systems con f an uffierground facility that relies on a mostly outward
dispersion of stormwater facility to the groundwater. These structures are
constructed a minimum of ° o'ot above the future wet -season water table. These systems
are most suitable for areas where the soil has high transmissivity. However, they do not
provide the nutrient uptake that is offered with vegetated infiltration systems.
Infiltration systems and seepage systems need a highly permeable substratum to allow the
stormwater runoff to percolate into the ground. Seepage systems do not require as much
land area as infiltration systems since they can be installed underground. However, the
future wet -season water table at the project site must be at least 1 foot below the seepage
structure.
4.3 LOW -IMPACT DEVELOPMENT OR DESIGN
4.3.1 DEFINITION
LID is an approach to stormwater and land use management that aims to replicate a more
natural hydrologic function by promoting infiltration, filtration, storage, and evaporation of
stormwater runoff. This approach focuses on conservation, use of on -site natural features,
20850-001-01
January 2022
Methods of Stormwater Trea
tPrAlae 35 of 95
Agenda Item #1.
site planning, and distributed stormwater management practices that are integrated into a
project's design especially its landscaping and open space. Stormwater management
through LID often includes a treatment train consisting of several different stormwater
management practices that combine to meet the stormwater quality objectives for the site.
Examples of practices that are often included in LID are:
Minimizing clearing, grading, soil disturbance, and compaction on a site.
Minimizing the impervious area on site.
Constructing pervious pavement.
■ Installing shallow bioretention systems.
■ Providing vegetated or grassed swales.
■ Providing vegetated filter strips.
■ Minimizing directly connected impervious areas.
■ Installing cisterns.
Harvesting stormwater.
4.3.2 REQUIREMENTS AS EXPRESSED IN THIS MANUAke(
Using a LID approach for stormwater managemenraged i e Village. However,
stormwater designs must demonstrate a net imp r 95-percent reduction in
pollutant loads. This can be demonstrated through that are accepted by SFWMD.
An example of one of these methods is us' MP Todeling software that is freely
available from the University of Central Flo a Management Academy
4.3.3 METHOD OF ACHIEVEME
A LID approach to stormwaterl
and continues throuCtctreatment practicesdetain, recharge, fildesign manuals in Fbut are not limited
its during the planning and site evaluation
nd design of the most appropriate stormwater
e I of stormwater management should be to retain,
mu stormwater as possible on a site. A variety of LID
this approach to stormwater management. These include
Low -Impact Development and Green Infrastructure: Pollution Reduction Guidance for
Water Quality in Southeast Florida (FDEP).
Sarasota County Low -Impact Development Guidance Document (Sarasota County).
Duval County Low -Impact Development stormwater Manual (Duval County).
Pinellas County Stormwater Manual (Pinellas County).
The manuals listed above provide design guidelines for a variety of LID stormwater
practices including:
Grassed conveyance swales.
Shallow bioretention.
Pervious pavement.
Stormwater harvesting.
Green roofs.
20850-001-01 4-4 36 Of 95
January 2022 Methods of Stormwater TreaprA
Agenda Item #1.
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Rainwater harvesting (cisterns).
Detention with biofiltration.
The Village will generally accept the LID practices and design considerations described in the
LID manuals referenced above, although the performance curves and tables provided in
these manuals do not necessarily apply to the Village's hydrologic conditions. Pollutant -load
reductions and sizing will need to be determined by the appropriate Florida- registered and
licensed professional.
20850-001-01 4-5 37 Of 95
January 2022 Methods of Stormwater TreaprA
Agenda Item #1.
A control structure is a device through or over which water is discharged from a stormwater
management system. Direct discharge occurs when stormwater is released through a
control structure to the receiving waterbody. If the discharge from the stormwater
management system is by a means other than a control structure (e.g., sheet flow or
spreader Swale), it is considered indirect discharge.
The primary purpose of a control structure in a detention facility is to release the calculated
runoff volume slowly over a specified period. Ina retention fa y, the control structure
allows for volumes exceeding the calculated retention volu o leave the system in a
manner that provides adequate downstream flood prote
5.3 TYPES OF CONTROL STRUCTURES
Direct discharge from a water management facile t eceiving body is usually achieved
through control structures such as weirs and orifice a following criteria must be met for
all methods of direct discharge:
1. Trash -collecting gratings must be on th
waters.
2. Detention facilities dischar
3. If a non -single-family resi4
contains a system with inlet
skimmer, or other Su
MP%
discharged.
4. Direct discharge will only be
configuration are able to ab;
res that discharge to surface
iust IF abo\A&he permanent pool.
al reater than 50-percent impervious or
Ile
areas, discharge structures must include a baffle,
ism for preventing oil and grease from being
wed to those areas that due to their large capacity or
concentrated discharges without erosion.
When using indirect discharge to release stormwater, a spreader Swale is commonly used.
The Swale is positioned parallel to the receiving body, and the side adjacent to the receiving
body is lower than the side opposite the receiving body. Figure 2 illustrates this form of
discharge. The Swale allows the water to flow into the receiving body but not flood the
adjoining property. This method works well when trying to maintain a proper water level in
wetlands that are used for stormwater management. The spreader Swale is also a treatment
facility for stormwater runoff. Runoff exceeding the first flush is allowed to enter the
wetland system via sheet flow.
20850-001-01 p5-1 38 Of 95
January 2022 Control Stru tpif�r
Agenda Item #1.
FINAL DRAFT
Figure 2 Spreader Swale (Indirect Discharge)
B
LEVEL LI
SWALE
FOREB�
INFLUENT
STORMWATERNEIIIIII
RECEIVING
WATERBODY
20850-001-01
January 2022
Control Structt&!& 39 of 95
Agenda Item #1.
Single-family and duplex homes that are not part of a master stormwater drainage system
may provide a Stormwater Management Plan following the guidelines established in the
Village of Tequesta Residential Stormwater Guidelines Brochure. The Stormwater Brochure
and the following design criteria generally use vegetated swales. However, other retention
practices may be used. The retention volume specified in these design criteria will provide
adequate stormwater treatment on a single-family/duplex lot to meet the Village
stormwater treatment requirements. However, calculations demonstrating a net
improvement or 95-percent reduction in nutrient loads may be submitted as an alternative
to using the retention volume specified in these design criteria. The stormwater calculations
must be completed by an appropriate Florida -registered and licensed professional.
The retention volume depends on the lot size and the stormwater management system
used. Stormwater treatment can also be provided using of retention systems such as
pervious pavement, exfiltration trenches, or shallow storm a vault systems.
Table 1 provides the required retention depths for single-family/d x lots that are not part
of a master stormwater treatment system. These are based on the e fective impervious
area, which is the sum of all the directly connected impervious areas and half the
unconnected impervious area. Unconnecte impervious area is an impervious area that
must drain over more than 20 feet of pe?fongle
before entering the stormwater system
or retention system. Directly connected im impervious area where stormwater
runoff is conveyed directly to ^onD
erwithout an opportunity to infiltrate.
Required Reteth Family/Duplex Lots
Effective Impervious Area Required Retention Depth Required Retention Depth
to Property Area Rati (feet) (inches)
0.20 0.138 1.66
0.25 0.142 1.70
0.30 0.15 1.80
0.35 0.161 1.93
0.40 0.175 2.10
0.45 0.186 2.23
0.50 0.201 2.41
0.55 0.214 2.57
0.60 0.228 2.74
0.65 0.242 2.90
0.70 0.256 3.07
0.75 0.269 3.23
0.80 0.283 3.40
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January 2022 Criteria for Single-Family/Duple;t L�
Agenda Item #1.
If swale(s) are used, they must meet the following criteria:
Runoff from the site must be drained to the swale.
The Swale length must be greater than its width.
The Swale side slope must be 4:1 (horizontal to vertical) or shallower.
The swale must be placed so that any natural areas to be preserved are not disturbed.
The swale must be at least 6 inches deep.
Swales should be vegetated. If a swale is not vegetated, a 6-inch layer of soil
amendment formulated to reduce nutrient loading must be installed directly below
the swale. Specifications and published nutrient -reduction test results for the soil
amendment media must be provided at the time of testing. Examples of acceptable
media are NutriGoneTM (distributed by EcoSense International) and Bold and Gold°
(distributed by Environmental Conservation Solutions).
Retention systems must discharge off site to prevent flooding, but should not discharge onto
adjacent private property. For retention systems, a control structure will allow runoff
exceeding the volume of the swale to be discharged to the receiving body. More than one
retention system may be on the property provided that each meets these criteria and the
total volume of the retention is at least the calculated volume. Vegetated swales may be
incorporated into the set -back area of land required by the Village. Appendix 5 contains
sample calculations for single-family/duplex lots. Florida -Friendly LandscaipingTM is
encouraged for vegetated swales. t***&, i
20850-001-01 p6-2 41 Of 95
January 2022 Criteria for Single-Family/Duple;t L�
Agenda Item #1.
FINAL DRAFT
Appendices
The Appendices contain the specific design criteria
for the BMPs discussed in this manual. These
criteria are based o est available knowledge in
stormwater manng ment. As technology dictates,
criteria will change.
Page 42 of 95
Agenda Item #1.
FINAL DRAFT
Stormwl
Checklist
Page 43 of 95
Agenda Item #1.
FINAL DRAFT
APPENDIX 4 — STORMWATER MANAGEMENT PLAN
CHECKLIST
20850-001-01 1-1 44 of 95
January 2022 Appendix 1 — Stormwater Management Plan Ch cl€Ri
Agenda Item #1.
FINAL DRAFT
Required Not Required Sufficient
A. Site Information
Detailed location map
Description of vegetative cover
■ Location and size of
preservation or mitigation areas
Vegetation protection plan
Soils map
■ Percolation test results
■ Current wet -season high-water
table
■ Future wet -season water table
Measures to be taken to
eliminate off -site adverse
impacts, such as turbidity,
flooding, etc.
Recent aerial photo (with year
aerial was taken)
Map of drainage basin
boundaries including off -site
areas
Map of floodplain and
elevations
B. Master Stormwater Management Plan
Location of all existing and
proposed on -site waterbodies
(including wetlands)
Location of all off -site wetlands
and waterbodies to be affected
by on -site drainage patterns
Location of all major control
structures and elevations
(preliminary construction plan
may be submitted for
conceptual review)
Right-of-way and easement
locations for stormwater
management systems,
including all areas reserved for
stormwater management
purposes
Location and size of on -site
water management facilities
20850-001-01 1-2 45 Of 95
January 2022 Appendix 1 — Stormwater Management Plan Ch cl€�i
Agenda Item #1.
Square footages, acreages, and
percentage of property
proposed as:
• Impervious surface
(excluding waterbodies)
■ Impervious surface
(waterbodies)
■ Pervious surface
■ Total square footage or
acreage of project site
Proposed grading plan
Treatment volume and
discharge rate (if applicable) for
stormwater management
system -4
C. Legal and Institutional Information
■ Entity responsible for operation
and maintenance of stormwater
management facility*
* If the operation and maintenance entity is to be a public boMW letter from the public body
confirming this must be submitted before staff approval. If the e tity is a homeowners' association,
documents verifying the existence of such organization and itstability to accept operation and
maintenance responsibility must be submitted before staff approval.
20850-001-01 1-3 46 Of 95
January 2022 Appendix 1 — Stormwater Management Plan Ch cl€�i
Agenda Item #1.
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'S
Page 47 of 95
Agenda Item #1.
A wet -detention facility is usually wet and allows for 1/2 inch of the required detained
volume (1 inch or the total of 2.5 inches times the percent of impervious area, whichever is
greater) to be discharged through a control structure in no less than 24 hours. Catch basins,
pipes, swales, or channels are used in areas with large amounts of impervious surface to
collect runoff and convey it to the detention facility. The required design criteria of a wet -
detention facility are detailed below:
The pond must be at least 0.25 acre and at least 50 feet wide for lakes exceeding
100 feet in length.
Irregularly shaped lakes may be narrower than 50 feet in some portions but should
average 50 feet in width.
Projects with single -owner entities or entities with a full-t' maintenance staff with
obvious interests in maintaining the areas for water-q purposes may have the area
and width criteria waived.
The lake slopes should be at least 4:1 (horizonta vertical) depth of 2 feet for
safety reasons and to allow a littoral habitat to m.�
The control structure is at one point in the detention Itility. Trash collection screens are
required on structures discharging to surface waters.
The control structure must be opposit the runoff entry into the facility to prevent
hydraulic short-circuiting and to ensure II n .
Wet detention cannot be used as the sole form of stormwater treatment. If wet detention
is used, at least 2.5 inches of dry -retention pre-treatment must be providled before
discharging into a wet -detention facility.
Guidance on sizing, designing, and permitting wet -detention facilities or exfiltration trenches
can be found in the SFWMD ERPApplicant's Handbook.
20850-001-01 2-1
January 2022 Appendix 2 - Wet -Detention Fa ilie 48 of 95
Agenda Item #1.
FINAL DRAFT
S
Page 49 of 95
Agenda Item #1.
Two types of dry -retention facilities exist — infiltration facilities and seepage facilities. The
most common form of infiltration is vegetated swales or dry -retention basins. Runoff is
routed to a vegetated swale or dry -retention basin directly or through a catch basin and
conveyance system. A control structure, usually a rectangular weir, is at one end of the
swale or basin to allow excess runoff to be discharged to a receiving body. A spreader swale
can also be used with this form of treatment. This type of discharge is most often used to
release water through sheet flow to wetland areas or to prevent erosion.
The seepage method of dry retention involves allowing the water to disperse outward from
an underground facility. The runoff is routed to a catch basin and is conveyed to a seepage
system. Exfiltration trenches are the most used type of seepage systems. They are used
with catch basins and consist of a perforated pipe surrounded coarse rock. Figure A4
shows that the system is in the ground, but above the fut ondition wet -season water
table. The length of the pipe depends on several factors ume of runoff to be
treated, the width of the trench, the depth to the wa table, a e hydraulic conductivity
of the soils.
An overflow system allowing for volumes exceeding theOtained volume is usually at the
end of the trench opposite the point where the runoff erritters the system and discharges to
the receiving waters. Although exfiltration trenches provide adequate stormwater treatment
and allow more land for development, they must be inspected regularly and periodically
cleaned. The pipe can become clogged and not allow proper seepage. When this occurs, the
pipe acts like a conduit for untreated stormwater. Ensuring that the upstream catch basins
are well maintained is one way f preventing failure of the trench.
Guidance on sizing, designing, and permitting dry -retention basins or exfiltration trenches
can be found in the I
D ERP Applicant's Handbook.
20850-001-01 3-1
January 2022 Appendix 3 — Dry -Retention Fa ilie 50 of 95
Agenda Item #1.
FINAL DRAFT
Figure A4 Typical Exfiltration Trench
TOP OF PAVEMENT OR FINISHED GRADE
MBANKMENTj�
cAGG REGATE
00 0 0 0 0
TRENCH 0 PERFORATED ^ 0
HEIGHT OR SLOTTED
0 PIPE 0
00' 0
0 0
0 0 r 0 0
RESERVOIRD
FILTER
I I FABRIC
REQUIRED
TREATMENT
VOLUME
TRENCH WIDTH" r.�
RTV RECOVERY BY
1 t T i SOIL INFILTRATION
SEASONAL HIGH GROUND WATER TABLE (SHGWT)
N TRENCH X-SECTION
.ion - of 12-02-09.d,,g
Source: Florida Department of Environmental Protection and Water Management Districts
Environmental Resource Permit Stormwater Quality Applicant's Handbook (March 2010 - Draft).
20850-001-01 3-2
January 2022 Appendix 3 - Dry -Retention Fa ilite 51 of 95
Agenda Item #1.
FINAL DRAFT
Page 52 of 95
Agenda Item #1.
FINAL DRAFT
APPENDIX 4 — CONTROL STRUCTURES
This Appendix contains design details for four types of control structures: a circular orifice, a
triangular orifice, a v-notched weir, and a rectangular weir.
Orifices and V-notched weirs are generally used with control structures associated with
detention facilities. These structures are commonly referred to as bleed -down mechanisms
and allow controlled release of a portion of detained volume over a specified period (usually
1/2 inch in 24 hours). Rectangular weirs are commonly used with detention and retention
facilities. In retention facilities, a rectangular weir allows excess runoff of the retained
volume to leave the facility. Rectangular weirs serve the same purpose as detention
facilities, using a circular or triangular orifice as the bleed -down device. Figures Al through
A3 (adapted from the SJRWMD ERP Applicant's Handbook Volume II, 2018) illustrate these
different types of control structures and their use. The retained (permanent pool) and
detained (attenuation storage) volumes used in deter ining the dimensions of the control
structures are calculated from the equations follow' ach drawing.
Figure Al Orifice Weirs
Emergency Q%rorflow *1111h1h,_X
Peak dlsehorge
alteakrollon storing■
(3f r1qulred) 0
9leeddown Drltloe
"WL .—..-. -.
_I_
Permoneni
P4;01 valume
Q
A = 4.8H3/2
FRONT VIEW
Where: Q = discharge (cubic feet per second [cfs]).
A = Area of orifice (square feet).
H = Head above orifice centroid* (feet).
*Centroid for a circular orifice is the center; centroid for a triangular orifice is two-thirds the distance
from the vertex.
20850-001-01 `FA4-1 53 of 95
January 2022 Appendix 4 — Control Stru qq
Agenda Item #1.
An orifice is a device that allows discharge from the center of the control structure. Simply,
it is an opening in the structure that lets water slowly pass. Detention facilities use orifices.
The rate that water is discharged depends on the cross -sectional area of the orifice.
Figure Al shows a circular -type orifice.
The circular orifice, as the name and illustration imply, is a round opening. The bottom of
the opening is at the control elevation. In the case of dry detention, the bottom of the circle
is at ground elevation. The most common method for constructing a circular orifice is
placing a polyvinyl chloride (PVC) pipe in the control structure. This pipe then discharges to
the receiving body or to a conveyance system discharging to the receiving body.
For maintenance purposes, the cross -sectional area of the orifice in any control structure
must be more than 6 square inches to ensure that the structure allows free flow of water
and does not become clogged. The formula following Figure Al is used to calculate the
cross -sectional area of the orifice.
Below is an example calculation for an orifice in a contro re that is part of a wet -
detention facility. The following assumptions are mad
H = 3 feet.
One-half inch of retained stormwater = 400,000 is feet.
• The discharge rate (Q) must be cal a
I_ 0,00 t3 1 hour
Q x 3600 sec
Q=4.63cfs
A = Q 1
4.8Hz
4.63
A = 11
(4.8 x 3a l
4.63
A — 8.31
A=0.56ft2
This meets the minimum dimensional criteria for orifices in detention facilities.
20850-001-01 `FA4-2 54 of 95
January 2022 Appendix 4 — Control Stru qq
Agenda Item #1.
E.nmarganor overflow
PEak dlaohorgr
qll*n�al��n ��ora��
(II r►qulrld)
Bland down vt
P�
Poo
V-notched weirs (Figure A2) are used With wet- and dry -detention facilities. The
configuration of the opening allows slow discharge of detained water over time. The rate of
discharge depends on the angle of the V-notch. When designing a control structure with a
V-notch weir, the angle is calculated using the formula below. Vdet refers to 1/2 inch of the
detained volume that must be discharged within 24 hours.
For maintenance and functional purposes, the angle of the V-notch should not be less than
20 degrees, that being the minimum to allowed for adequate flow of water and to prevent
blockage of the weir.
The following is an example calculation for a V-notched weir, which is part of a 2-foot-deep
dry -detention facility, making the following assumptions:
H = 2.0 feet (depth of detention facility).
Vdet = 500 f tZ , therefore, Vdet = 0.01 acre foot.
0 = 2 arctan 9_(0.492)((V_det/HA2.5 ))S.
0 = 2 arctan [f(0.492)((0.01/2A2.5 )),Y.
0 = 2 arctan(0.03).
0 = 3.19 degrees.
20850-001-01 4-3 55 of 95
January 2022 Appendix 4 — Control Stru ttfgi
Agenda Item #1.
Since the calculated angle is less than 20 degrees, and the angle of the V-notch must be at
least 20 degrees, this facility will need a 20-degree angle. Since most of the stormwater
management facilities reviewed by Village staff will be small, calculations in which the angle
of the notch is less than 20 degrees will be common.
S
I
Pook dl191,orgo
Oftntrollah ilorepe
(1.l roqulre F - -
Mad Uowi
control
elevation
A rectangular weir (Figure A3) is a structure that allows excess volumes of water to leave a
stormwater management facility. A rectangular weir is used with retention facilities to
discharge runoff exceeding the retained volume. A rectangular weir can also be used with a
detention facility that has an orifice for the delayed release of stormwater runoff. The
rectangular weir allows the discharge of excess runoff during severe rain events. The weir is
constructed on top of the control structure. Rectangular weirs are used in areas where a
receiving waterbody exists for excess runoff or a method of conveying excess runoff to a
receiving waterbody.
Control structures can be made of several different types of materials. Those commonly
used include concrete, aluminum, and earthen material. PVC pipe is often used as a bleed -
down mechanism (circular orifice).
All control structures must discharge to a receiving body of water that has the capacity to
handle the discharge without causing erosion. If no receiving waterbody exists adjacent to
the stormwater management facility, some system for conveying the stormwater must be
provided and is commonly achieved by using swales, culverts, or similar mechanisms.
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APPENDIX 5 — SINGLE-FAMILY/DUPLEX LOT SAMPLE
CALCULATIONS
An 8,000-square-foot lot with a house, patio, and driveway using dry -retention swales:
House 1,600 square feet (800 directly connected and 800 unconnected).
Driveway 560 square feet.
Concrete Patio 840 square feet.
Total impervious 3,000 square feet.
Effective Impervious (sum of directly connected impervious and half the unconnected
impervious) 2,600 square feet.
Total lot size = 8,000 square feet.
Ratio of effective impervious area to lot area = 32.5
Required retention depth = 0.161 feet (from Tabl
The following equation is used to size the Swale:
Required Swale volume (cubic feet) = effectiv
0.161-foot required retention depth (fe
Required Swale volume = 2,600 square f
Required Swale volume = 418.6 cubic feet.
ous area (square feet) x
Assuming a 4:1 (horizontal to vertical) slope for the swales to a 1-foot depth and a 2-foot
bottom width, the cross- Tonal area (A) of the Swale is 6.0 square feet.
Therefore, the requ' length oQJhe Swale is determined as follows:
■ Required length of Swale (fe = required volume/A.
■ Required length of Swale 18.6 cubic feet/6 square feet.
■ Required length of Swale — 69.8 feet.
In areas where a receiving waterbody is adjacent to the property, a rectangular weir should
be placed at one end of the Swale for discharge of excess runoff. To reduce the required
length of the swale, explore opportunities to reduce the directly connected impervious area
by replacing impervious surfaces with pervious surfaces and evaluate minimizing the site
disturbance. These changes would reduce the required Swale length.
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January 2022 Appendix 5 —Single Family/Duplex Lot Sample Calcul ti
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Page 59 of 95
Agenda Item #1.
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Water Management District, Technical Publication 87-5, West Palm Beach, Florida.
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January 2022 Appendix 6 — BibliogaRqe
Agenda Item #1.
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Beach, Florida.
South Florida Water Management District (SFWMD). 2020. Environmental Resource Permit
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St. Johns River Water Management District (SJRWMD). 2018. Environmental Resource
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Whalen, PJ, and Cullum, MG. 1988. As Assessment of Urban Land Use/Stormwater Runoff
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January 2022 Appendix 6 — BibliogaRqe