R25-140 RESOLUTION NO. R25-140
2
3 A RESOLUTION OF THE CITY COMMISSION OF THE CITY OF BOYNTON
4 BEACH, FLORIDA, ADOPTING THE BOYNTON BEACH WATERSHED
5 MANAGEMENT PLAN; AND FOR ALL OTHER PURPOSES.
6
7 WHEREAS, the 2017 Coordinator's Manual for the National Flood Insurance Program
8 (NFIP) Community Rating System (CRS) introduced a series of credit options for "community
9 efforts to anticipate" future flood risk in relation to climate change (FEMA 2017, pg. 110-15); and
10 WHEREAS, since sea-level rise is expected to be an increasingly critical issue for floodplain
11 management, many of the CRS credit options and assessment criteria for coastal communities
12 specifically refer to studies of sea-level rise impact on future hydrologic conditions and the local
13 drainage systems; and
14 WHEREAS, the 2017 Coordinator's Manual notes that a mandatory prerequisite for a
15 community to achieve CRS Class 4 status is that the community must"receive credit for managing
16 the impacts of a 100-year storm and/or sea level rise, where applicable, based on a watershed
17 management plan" (FEMA 2017, Credit 450, pg. 14); and
18 WHEREAS, each improvement in CRS Class rating (starting from a Class 10) translates into
19 a 5% premium discount on qualifying NFIP policyholders within the Special Flood Hazard Area
20 (SFHA), meaning that a CRS Class 4 status makes qualified policyholders within the community
21 eligible for a 30% total premium discount; and
22 WHEREAS, the City is currently rated as a CRS Class 5 community and achieving CRS Class
23 4 status would result in an additional 5% premium discount for qualified NFIP policyholders within
24 the SFHA; and
25 WHEREAS, a qualified watershed management plan is defined as a mandatory
26 prerequisite for CRS Class 4 status and any further NFIP premium discounts that Islamorada
27 residents may receive through the CRS program will likely require the development and adoption
28 of a watershed management plan that meets or exceeds the criteria outlined in the 2017
29 Coordinator's Manual; and
30
31
32 WHEREAS, the CRS Watershed Master Plan — Prerequisites for Section 452b require the
33 City to adopt a watershed master (or management) plan that evaluates the future conditions,
34 including the impacts of a median projected sea level rise (based on the National Oceanic and
35 Atmospheric Administration's (NOAA's) "intermediate-high" projection for the year 2100) on the
36 local drainage system during multiple rainfall events, including the 100-year rainfall event; and
37 WHEREAS, the City Commission, upon the recommendation of staff, has deemed it in the
38 best interests of the City's citizens and residents to adopt the Boynton Beach Watershed
39 Management Plan.
40
41 NOW, THEREFORE, BE IT RESOLVED BY THE CITY COMMISSION OF THE CITY OF BOYNTON
42 BEACH, FLORIDA, THAT:
43 SECTION 1. The foregoing "Whereas" clauses are hereby ratified and confirmed as
44 being true and correct and are hereby made a specific part of this Resolution upon adoption.
45 SECTION 2. The City Commission of the City of Boynton Beach, Florida, does hereby
46 adopt the Boynton Beach Watershed Management Plan as further detailed in Exhibit A, attached
47 hereto.
48 SECTION 3. This Resolution shall take effect in accordance with the law.
49
50
51
52 [SIGNATURES ON THE FOLLOWING PAGE]
53
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FINAL
CITY OF BOYNTON BEACH
WATERSHED
MASTER PLAN
March 20, 2025
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CITY OF BOYNTON BEACH
WATERSHED MASTER PLAN
Watershed Master Plan Under CRS Activity 450—Storm water Management
Prepared For:
City of Boynton Beach, Florida
100 E. Ocean Avenue
Boynton Beach, Florida 33435
Prepared By:
Collective Water Resources, Inc. /
250 S Australian Avenue, Suite 1110 (�41
West Palm Beach, Florida 33401
Collective
WATER RESOURCES
Lori Lehr, Inc.
3569 Stabile Road
St.James City, Florida 33956
Erin Deady, PA
54-1/2 SE 6th Avenue
Delray Beach, Florida 33483 ERIN L. DEADY, P.A.
DIGITAL VERSION
See hard copy for official signed and sealed version
Elizabeth M Perez, P.E. Joel G.Jordan, P.E.
Florida P.E. No. 61023 Florida P.E. No. 51986
Project Manager, Watershed Master Plan Principal Engineer
City of Boynton Beach 2025 Watershed Master Plan
Table of Contents
Figure List 4
Table List 5
List of Appendices 6
Appendix A: Model Methodology 6
Appendix B: Summary of Data Collection and Structure Inventory 6
Appendix C: Summary of CRS Scoring for the City of Boynton Beach 6
Appendix D:Article VII 6
Appendix E: Environmental Resource Permits Used to Parameterize Model 6
Appendix F: ICPR Model Output(For All Simulations) 6
Appendix G: Current Conditions Floodplain Maps for All Design Storms 6
Appendix H: Future Conditions Floodplain Maps for All Design Storms 6
Acknowledgements 7
List of Acronyms 8
Glossary 10
1. Executive Summary 12
2. Introduction 14
3. City Profile and Location 15
4. Data Inventory and Collection 17
4.1 City Watersheds and Ground Characteristics 17
4.1.1 Topography 22
4.2 Soil Types (USGS Soils Data) 24
4.3 Impervious Surface 26
4.4 Wetlands and Natural Areas 28
4.5 City Stormwater Inventory and Infrastructure 30
4.6 Locations of Critical Facilities, Cultural/Historical Resources, and Other Places of Interest 33
4.7 Vulnerable Areas and Their Descriptions 35
4.7.1 Areas Prone to Flooding(City-Identified) 37
4.8 Natural and Constructed Drainage Systems and Channels 39
4.8.1 Canals and Surface Water Features 39
4.9 Existing Regulations and Plans in Place for Reducing Flood Risks 41
4.10 Inventory of Data Availability 52
Page 1 of 129
City of Boynton Beach 2025 Watershed Master Plan
4.10.1 Land Use and Land Classification 52
4.10.2 Groundwater 54
4.10.3 Environmental Resource Permits 57
4.10.4 National Oceanic and Atmospheric Administration (NOAA) Historical Trends and SLR Estimation 57
4.10.5 Southeast Florida Climate Compact 58
4.11 Studies of Existing Development and the Potential Impact of Redevelopment 60
5. Summary of ICPR4 Modeling 63
5.1 Boundary Conditions and Model Datum 65
5.2 Hydrology 65
5.3 Hydraulics 65
5.4 Special Notes on the Boynton Beach Watershed and Boundary Conditions 66
5.5 General Notes on Errors, Warnings, and Production Runs 69
6. Summary of ICPR4 Modeling for Current Conditions 69
6.1 Design Storms for Current Conditions 69
6.1.1 Detailed Tailwater Assumptions (Mean Tide, Mean High Water,etc.)for Current Conditions 70
6.2 System Response to the Current 3-, 10-, 25-,and 100-Year Storm Events 70
7. Summary of ICPR4 Modeling for Future Conditions 72
7.1 Future Land Use/Fully Developed Conditions 72
7.2 CRS-Compliant ICPR4 Model Run for 2100 using NOAA Intermediate-High 74
7.3 Future Rainfall 74
7.4 System Response to the Future 3-, 10-, 25-, and 100-Year Storm Events 75
8. Results 77
8.1 Change in Runoff from Current to Future, Fully-Developed Conditions 77
9. Strategy and Action Plan to Ensure that the Flood Hazard for the 3-, 10-, and 25-Year Events are Not Increased by
Future Development 78
9.1 Regulations 78
9.2 Structural Controls for Water Quality and Quantity 79
9.2.1 Ongoing(2025-2026) Projects 79
9.2.2 Recommended Structural (Infrastructure) Projects 83
9.2.3 Recommended Prioritization of Structural Projects 116
9.3 Non-Structural Controls for Water Quality and Quantity 118
9.3.1 Stormwater Manual 118
Page 2 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.3.2 Maintain and Strengthen Collaboration and Partnerships 119
9.4 Protection of Sensitive Natural Areas 121
9.4.1 Protection of Lake Ida and the Greater Central Palm Beach County Chain-Of-Lakes 121
9.4.2 Protection of Existing Preserves and Wetlands 123
9.5 Public Engagement 123
9.6 Revised Level of Service 124
9.7 Low Impact Development and Green Infrastructure 126
9.8 Stormwater Retrofits—Make them Routine 126
10. Citations 127
Page 3 of 129
City of Boynton Beach 2025 Watershed Master Plan
Figure List
Figure 1. City of Boynton Beach Location and Municipal Boundaries 16
Figure 2. City of Boynton Beach Major Watersheds (SFWMD, 2021) 18
Figure 3. SFWMD AHED Major Watersheds (SFWMD, 2021) 20
Figure 4. SFWMD and LWDD Watershed Boundaries and Natural Areas (2023) 21
Figure 5. Topography and Generalized Ground Surface Features of Boynton Beach, Florida 23
Figure 6. City of Boynton Beach SSURGO Soil Map Units (NRCS, 2022) 25
Figure 7. Impervious Surface near and within the City of Boynton Beach 27
Figure 8. Florida Conservation Lands-Florida Natural Areas Inventory (FNAI, October 2023) 29
Figure 9. City of Boynton Beach Stormwater Inventory and SFWMD ERPs 32
Figure 10. City of Boynton Beach-Other Areas of Interest(FGDL, 2023) 34
Figure 11. FEMA DFIRM Panels, Palm Beach County (FEMA, 2024) 36
Figure 12. City-Identified Areas Prone to Flooding 38
Figure 13. SFWMD Canals and Structures (AHED, 2021) 40
Figure 14. Boynton Beach Study Area Land Use and Land Classification (SFWMD, 2017-2019) 53
Figure 15. Depth to Water Table, inches (USGS NRCS, 2022) 56
Figure 16. Lake Worth Pier SLR (1970-2022, NOAA) 58
Figure 17. CDM Smith Model for Boynton Beach (Downtown Study, 2023) 62
Figure 18.The City of Boynton Beach and WMP-Defined Watershed Boundary 64
Figure 19. ICPR4 Model Schematic for Boynton Beach 68
Figure 20. Future Land Use for the City of Boynton Beach 73
Figure 21. Stormwater Projects Currently Underway 80
Figure 22. City Outfalls with Recently Installed Pollution Control Boxes 82
Figure 23. Final Areas of Concern from the Boynton Beach WMP 84
Figure 24. Area of Concern M-1 87
Figure 25. Area of Concern M-2 89
Figure 26. Area of Concern M-3 91
Figure 27. Area of Concern M-4 93
Figure 28. Area of Concern M-5 95
Figure 29. Area of Concern M-6 97
Figure 30. Area of Concern MDS-7 100
Figure 31. Area of Concern MDS-8 104
Figure 32. Area of Concern MDS-9 106
Figure 33. Area of Concern MDS-10 108
Figure 34. Area of Concern MDS-11 110
Figure 35. Area of Concern MDS-12 112
Figure 36. Area of Concern MDS-13 114
Figure 37: Unincorporated Areas with Flooding 120
Figure 38. Interaction of Palm Beach County's Eastern Chain-of-Lakes and Boynton Beach 122
Page 4 of 129
City of Boynton Beach 2025 Watershed Master Plan
Table List
Table 1. City of Boynton Beach Stormwater Inventory Summary 31
Table 2: Land Use(2017-2019)for Boynton Beach Study Area (SFWMD, Quality Controlled by Collective Water
Resources, LLC) 54
Table 3: Study Area ERPs and CUPs Summary(SFWMD) 57
Table 4: Adjusted MHHW for NOAA Lake Worth Pier Gauge 59
Table 5: Storm Surge Minimum and Maximum Elevations with SLR from 2017 NOAA Intermediate-Low and Intermediate-
High Curves (ft, NAVD88) 59
Table 6: Selected Design Storm Depths (in inches) and Durations for Current Conditions 69
Table 7: Extent of Flood Inundation for Existing Conditions Across All Design Storm Events 71
Table 8: USGS Rainfall Change Factors and Future Rainfall 75
Table 9: Flood Extent for Future Conditions Within City Limits(by Acreage)for All Storm Events 76
Table 10: Flood Extent for Future Conditions Within City Limits(by Percentage)for All Storm Events 76
Table 11: Change in Runoff from Current to Future (Fully-Developed Summary) 77
Table 12:Areas of Concern (as depicted in Figure 23) 85
Table 13: Prioritized Structural Projects and Initiatives 117
Table 14: Recommended Level of Service Criteria 125
Page 5 of 129
City of Boynton Beach 2025 Watershed Master Plan
List of Appendices
Due to the size of these items when converted to PDF, they are provided electronically as separate files.
Appendix A: Model Methodology
Appendix B: Summary of Data Collection and Structure Inventory
Appendix C: Summary of CRS Scoring for the City of Boynton Beach
Appendix D: Article VII
Appendix E: Environmental Resource Permits Used to Parameterize Model
Appendix F: ICPR Model Output (For All Simulations)
Appendix G: Current Conditions Floodplain Maps for All Design Storms
Appendix H: Future Conditions Floodplain Maps for All Design Storms
Page 6 of 129
-
City of Boynton Beach 2025 Watershed Master Plan
Acknowledgements
The City wishes to thank the following agencies and local governments for their assistance in preparing this Watershed
Master Plan:
• The Lake Worth Drainage District
• The South Florida Water Management District
• The Florida Department of Transportation
• Palm Beach County
• The City of West Palm Beach
The consultant team for this Watershed Master Plan included the firms of Collective Water Resources, LLC, Lori Lehr, Inc.
and Erin Deady, PA.The consultant team also wishes to thank CDM Smith for their assistance in obtaining information
from their previous work products.
Page 7 of 129
IMES
City of Boynton Beach 2025 Watershed Master Plan
List of Acronyms
AAE = Adaption Action Elevation
AHED=Arc Hydro Enhanced Database
BFE = Base Flood Elevations
CCVA= Climate Change Vulnerability Assessment
CRS = Community Rating System
CUP = Consumptive Use Permits
DEM = Digital Elevation Model
DFIRM = Digital Flood Insurance Rate Map(s)
ERP = Environmental Resource Permit
FAC= Florida Administrative Code
FDEM = Florida Division of Emergency Management
FDEP= Florida Department of Environmental Protection
FDOT= Florida Department of Transportation
FEMA= Federal Emergency Management Agency
FGDL= Florida Geographic Data Library
FIS= Flood Insurance Study
FLUCCS= Florida Land Use, Cover and Forms Classification System
FNAI = Florida Natural Areas Inventory
FPLOS= Flood Protection Level of Service
GIS = Geographic Information Systems
H&H = Hydrologic and Hydraulic
HMGP = Hazard Mitigation Grant Program
ICPR = Interconnected Channel and Pond Routing (also called the "Stormwater Model" throughout this document,the
City used version 4 of this model for the Watershed Master Plan)
ISO= International Organization for Standardization
Page 8 of 129
City of Boynton Beach 2025 Watershed Master Plan
LiDAR = Light Detection and Ranging
LOS= Level of Service
LULC= Land Use Land Classification
LWDD = Lake Worth Drainage District
MHHW= Mean Higher High Water
NAVD88 = North American Vertical Datum of 1988
NFIP = National Flood Insurance Program
NOAA= National Oceanic and Atmospheric Administration
NRCS= Natural Resources Conservation Service
SFWMD = South Florida Water Management District
SLR= Sea Level Rise
SSURGO= Soil Survey Geographic Database
SWMM = Storm Water Management Model
TMDL=Total Maximum Daily Load
USGS= US Geographical Service
WMP =Watershed Master Plan
VA = Vulnerability Assessment
Page 9 of 129
WNW
City of Boynton Beach 2025 Watershed Master Plan
Glossary
Alternative: A conceptual and preliminary project concept evaluated as part of this Master Plan.
Adaptation: Adjusting to actual or expected future climate.
Climate Change: Long-term change in the average weather patterns that have come to define Earth's local, regional, and
global climates.
Collective:The Collective Water Resources Team, or the consultant team that worked on the Watershed Master Plan for
Boynton Beach (consulting firms are detailed in the acknowledgements section).
Gray Infrastructure: Within stormwater, infrastructure designed by engineers using classical techniques, technologies,
and methods—generally to convey stormwater away from populated areas. Generally, it refers to the color of
stormwater pipes, concrete, structures, etc.
Green Infrastructure:The US Environmental Protection Agency defines green infrastructure as a cost-effective, resilient
approach to managing wet-weather impacts that provides many community benefits.
ICPR: Interconnected Channel and Pond Routing (also called the "Stormwater Model" throughout this document,the
City used version 4 of this model for the Watershed Master Plan)
Nuisance Flooding: Flooding that does not result in property damage and/or reduce public safety.
Mitigation: Reducing the causes of flooding and/or climate change to avoid significant human interference with climate
system
Rainfall-Induced Flooding: Flooding due to the accumulation of rainwater on normally dry land. This can occur in various
ways including when a river/pond/lake overflows its banks or when urban drainage systems fail or are overwhelmed by
the water trying to enter the system. Rainfall-induced flooding can happen when it rains for an extended period, when it
rains heavily in a short amount of time, or both. Rainfall-induced flooding is often characterized by how likely that level,
or extent, of flooding is to reoccur or be exceeded.
Recommendation: A final project concept developed as part of this Master Plan.
Resilience:The ability to anticipate, prepare for, and adapt to changing conditions and withstand, respond to, and
recover rapidly from disruptions.
RISK Mapping: Risk Mapping, Assessment, and Planning for the purposes of this study refer to the ongoing Federal
Emergency Management Agency (FEMA) coordinated Coastal Mapping initiative that is underway for Palm Beach
County.
Sea Level Rise: Relative rise of the mean sea level over time. Although the local tides vary daily, seasonally, and from
year to year, the average of all measurements over a specified period is called Mean Sea Level Rise.
Page 10 of 129
City of Boynton Beach 2025 Watershed Master Plan
Tidal Flooding: Indicates above-normal high-tide events, unrelated to a storm,where water levels flow over the tops of
sea walls and onto streets or force water into stormwater outfalls. The flooding may disrupt traffic and damage
infrastructure.
Vulnerability:The susceptibility of exposed assets based on the two core concepts: (1) potential impact—the degree to
which an asset is affected due to its sensitivity and (2) adaptive capacity—the ability of the asset cope with a potential
impact with minimal disruption or cost.
Page 11 of 129
City of Boynton Beach 2025 Watershed Master Plan
1. Executive Summary
The City of Boynton Beach prepared this Watershed Master Plan (WMP) under Community Rating System (CRS)Activity
450—Stormwater Management Project to provide a tool that can be used in decision-making to reduce flooding.This
project was initially created out of the City's desire to create a holistic and Citywide Stormwater Plan.The data needed
to develop the WMP, according to CRS requirements for Activity 450,were collected and reviewed. Using the available
data, several sets of hydrologic scenarios were analyzed to identify the exposure to flooding for both current and future
conditions. Future conditions for this project,which can be impacted by development and redevelopment,climate
change, and sea level rise (SLR), are the 2040, 2070, and 2100 planning horizons.Additionally,flood impacts were
analyzed for 2100 using National Oceanic and Atmospheric Administration (NOAA) Intermediate-High SLR scenario.
Results were used to evaluate sensitivity to current and potential flooding impacts and identify areas of concern.
Strategy and action plans were provided to ensure that the flood hazards of 3-, 10-, and 25-year storm events are not
increased by future development.
City staff collaboratively developed a suite of watershed management measures that are diverse in scope.These
measures can be applied equitably across the City and are supported by the scientific findings of this WMP and previous
City studies.This diverse menu of strategies ensures that the City is more resilient to potential future changes in the
watershed. When combined, implemented, and monitored correctly,these strategies will likely provide appreciable and
synergistic flood relief in future conditions for storm events up to and including the 25-year storm event. Because this
study also included information up to the 100-year storm event for both current and future conditions,the City can
expect some relief in larger storm events by applying these measures. However,given the size of those events and the
hydrography of South Florida,the City cannot completely mitigate larger storm events and the City's success in flood
mitigation will vary in future years.
Compared to other South Florida communities, Boynton Beach has an unusually high number of canals that weave
through the City and are controlled by the South Florida Water Management District (SFWMD) and Lake Worth Drainage
District (LWDD). Much of the City was developed prior to modern stormwater permitting and engineering/development
requirements. Due to this issue, the City has an exceptionally high level of complexity for effective future flood
mitigation.The actions of these external agencies will considerably affect most of the City's watershed and will be
discussed throughout this report.The City cannot adequately address the majority of flooding via piecemeal engineering
projects,which is the practice of some communities via traditional stormwater master planning in South Florida. Due to
all of these constraints,a scientific,adaptive,watershed,and all-solutions approach is likely the only way the City can
effectively address flooding in future conditions.
Given the significant challenges facing the City, a strong and diverse portfolio of flood mitigation measures is
recommended.These measures include traditional engineering, also referred to as structural measures, sustainable and
nature-based solutions, and policy considerations, among other non-structural initiatives.The City prioritizes long-term
sustainability and considered issues related to energy consumption and pollutant reduction as significant parts of the
development of these measures.The table that follows summarizes prioritized structural initiatives recommended by
the WMP.
Page 12 of 129
City of Boynton Beach 2025 Watershed Master Plan
Prioritized Structural Projects and Initiatives
Suggested Project Final Project Likelihood of
Project ID Name Suggested Partners Grant Award Overall Timeframe and Notes
Initiation
Seacrest Boulevard Community leaders,
Corridor Florida Department of Begin Phase 1 Immediately(this is
MDS-7 Adaptation Transportation Very High a lengthy and two-pronged
Initiative
(FDOT),and Palm project)
Beach County
Leisureville Community leaders, High (with Begin Coordination and Grant
M-3 Adaptation Palm Beach County, LID/Water Preparation Immediately(this is a
Years 0-3 Initiative and LWDD Quality/Nature lengthy project)
Based Solutions)
Lawrence Road
Neighborhood
Outreach and Community leaders Immediate(due to potential issues
M-6 Low
Stormwater and LWDD with existing LOS)
Engineering
Support
South Gateway
Blvd Stormwater Community leaders
M-4 Low Immediate
Monitoring and LWDD
Program
Years 2-4
South Lake Drive
Neighborhood
MDS-8 Outreach and Community leaders, Low Immediate
Engineering
LWDD
Support
South Congress
M-1 Avenue Resilience Community leaders, Low Near Term
FDOT, and LWDD
Initiative
Southeast Boynton
M-2 Community leaders Moderate Near Term
Resilience Initiative
Years 5— Southeast Miner
10 Road
Neighborhood Community leaders,
M-5 Outreach and Low Near Term
LWDD, and FDOT
Stormwater
Engineering
Support
NE 9th Avenue
MDS-12 Neighborhood Community Leaders Low Near Term
Improvements
Page 13 of 129
City of Boynton Beach 2025 Watershed Master Plan
2. Introduction
The City of Boynton Beach hired a consultant team to prepare this Watershed Master Plan (WMP)as part of a holistic
effort to better understand and ultimately mitigate water resources and stormwater challenges affecting the City, both
now and in the future.As specified by the 2017 edition of the National Flood Insurance Program (NFIP) Community
Rating System (CRS) Coordinator's Manual and 2021 Addendum,this WMP analyzes potential flooding impacts,
recommends mitigation measures to alleviate flooding based on current levels of service (LOS),and is to be used as a
guide for future planning.This project also afforded the City a valuable opportunity to enhance relevant datasets,
explore climate vulnerability, and modernize stormwater data and information to be useful in future planning efforts.
The City placed scientific integrity and equity at the forefront of this study, providing an invaluable opportunity to study
all of the City's watersheds in detail and thoroughly.
This project received grant funding from the Florida Division of Emergency Management (FDEM) under the Hazard
Mitigation Grant Program (HMGP).This report is subject to Grant Agreement#4337-004 and is intended to meet the
grant requirements.This report will also meet the approved City contract requirements (#UTL23001) and all activities
and deliverables described in that contract.
Page 14 of 129
City of Boynton Beach 2025 Watershed Master Plan
3. City Profile and Location
The City of Boynton Beach, situated on the southeast boundary of Palm Beach County, is a highly developed coastal
community on the southeast coast of Florida. Boynton Beach is bordered by the Intracoastal Waterway and the Atlantic
Ocean to the east and is surrounded by urban coastal communities, including the City of Lake Worth Beach and Town of
Lantana to the north,the City of Delray Beach and Town of Gulf Stream to the south, and the Towns of Briny Breezes
and Ocean Ridge to the east. The City is also bordered by portions of unincorporated Palm Beach County to the west.
With a population of 80,859 as of July 2022 and a municipal area of 10,601 acres, the City is the third largest
municipality in Palm Beach County (US Census Bureau). Its rapidly growing population and ongoing urban
transformation with redevelopment and mixed-use complexes make it one of the more highly developed areas within
Palm Beach County.
Given its coastal location, the City is known for lower elevations and high water tables. It is also close to other
waterbodies, such as Lake Ida to the south and Lake Worth Lagoon to the east. The Lake Worth Drainage District
(LWDD), which manages the secondary drainage system in this portion of central Palm Beach County, controls inflows
via a network of canals throughout the City.
Considering these factors, stormwater management is a critical aspect of urban planning in Boynton Beach. As a vibrant
and forward-thinking City, Boynton Beach is committed to integrating stormwater management practices into its overall
planning framework. Please see Figure 1 for the City's overall location and municipal boundaries.
Page 15 of 129
City of Boynton Beach 2025 Watershed Master Plan
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Page 16 of 129
MMIW
City of Boynton Beach 2025 Watershed Master Plan
4. Data Inventory and Collection
This section summarizes the extensive data inventory completed for the City of Boynton Beach in preparing this study.
4.1 City Watersheds and Ground Characteristics
The City is within the regional jurisdiction of the South Florida Water Management District (SFWMD) and the service
area of the Lake Worth Drainage District (LWDD). Figure 2 shows the major watersheds that intersect the City. Overall,
the City's topography and hydrologic gradient slope from west to east.The City is at an intersection of three major
SFWMD watersheds, which logically follow some of the major primary canals that pass through the City: the C-16 and E-
4 canals.The majority of the City outfalls to the Intracoastal Waterway, as shown in Figure 2. These primary SFWMD
canals, or primary system, play a significant hydrologic role throughout the City. Additionally, the Lake Worth Lagoon
further influences the City's hydrologic dynamics. This waterbody discharges to the Atlantic Ocean from the Boynton
Beach Inlet in the Intracoastal Waterway.
The City is also bordered by Lake Osborne to the north and Lake Ida to the south. Both waterbodies are of regional
importance to the City and adjacent stakeholders.These lakes contribute to the overall hydrologic balance of the region
and play a crucial role in water supply, flood control, and ecosystem health. Understanding the interconnectedness of
these major watersheds and waterbodies is essential for effective watershed management and sustainable development
in Boynton Beach.
Page 17 of 129
City of Boynton Beach 2025 Watershed Master Plan
City of Boynton Beach M ? Palm Beach County
Watershed Master Plan
Sources:
City Boundary City of Boynton Beach
f rr
Major Roads-Palm Beach County(2023) ��.-
Canals-SFWMDAHED(2021) ake f 2 City of Boynton Beach`
Waterbody-SFWMD AHED(2021) \ -..
��•OUf172
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City of Boynton Beach
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/ _ ;` LEGEND
-':ci City of Boynton Beach
i • Major Watersheds
Iii/ f , —Major Roads
r, Canals
LW6C L-3
,�, WaterbodY type
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/
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at s Ocean
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0 5,000 10,000 Feet
Figure 2. City of Boynton Beach Major Watersheds(SFWMD, 2021)
Page 18 of 129
City of Boynton Beach 2025 Watershed Master Plan
The SFWMD's Arc Hydro Enhanced Database (AHED) is an important component of the data inventory in the
development of this project because it provided an official database of the primary hydrographic data features within
the SFWMD. In some instances,the AHED was leveraged in support of the creation of the City's Interconnected Channel
and Pond Routing(ICPR) model. Figure 3 illustrates the major AHED watersheds in Boynton Beach and the surrounding
upstream inland area, highlighting the interconnected nature of the hydrologic system in the region. Figure 4 shows the
placement of the City against the boundaries of LWDD and some of the major natural features within the City.
Page 19 of 129
City of Boynton Beach 2025 Watershed Master Plan
•
City of Boynton Beach
s.
Watershed Master Plan �. "' •• ..,
Sources: .i. J . '#L
City Boundary-City of Boynton Beach C Palm Beach Coutt P.
Lake Worth Drainage District-LWDD(2023) _
Major Watershed-SFWMD AHED(2021) rr City of Boynton Beech „..„
Florida Natural Areas Inventory-Palm Beach
County(2023) South Florida ....
Basemap-ESRI,USGS Watershed
\ Management
ii, 1
District
/ City of Boynton Beach
SFWMD Watersheds and LWDD Boundary 't
_� S
�.. 1 .
5 k
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Area 2B
QCfy of Boynton Beach
'
Palm Beach County
Fvergtades&Francis S. Taylor 1—
_ ---- Major Watersheds
t ( W dlife Management Area l l WA Lake Worth Drainage District
Conservation Land Owner
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l / t 1 t R F ovate
\V( F. �.Y I J `�--� State
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Figure 3.SFWMD AHED Major Watersheds(SFWMD, 2021)
Page 20 of 129
IIIIIMIr
City of Boynton Beach 2025 Watershed Master Plan
..,
City of Boynton Beach , - Palm Beach County
Watershed Master Plan LANTANA'SCR
source, 'a".''J
City Boundary C)ty of Boynton Bra:�� -"_ iii~.
take Wath Ora nage Dntrct IWOD IiO231 1,3 •
Major Watershed SrWMD AHED 12021) ', `\'V
City of Boynton Beach*
•
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{lords Natural Areas Inventory Dalen Beach County 120211 eked.- U
Basemap ESIU.uses s'ur '. .+.•- •-.-•.--
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i St WM0 Watersheds and IWOD Boundary
r 1 r. f- , •,
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' r: •
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k i L
p City of Boynler Bead
Ls•., Major Watersheds
• • Lake Worth Drainage District
' Canals
.+s
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si Private
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Figure 4. SFWMD and LWDD Watershed Boundaries and Natural Areas (2023)
Page 21 of 129
MOM
City of Boynton Beach 2025 Watershed Master Plan
4.1.1 Topography
A Digital Elevation Model (DEM) was created based on 2017-2018 Light Detection and Ranging (LiDAR)flight data
obtained from Palm Beach County as part of a grant provided by the US Geological Survey(USGS). Figure 5 presents the
DEM for the study area.
Within the City limits, surface elevations range from -2.3 to 56.3 feet, North American Vertical Datum of 1988 (NAVD88),
with the highest elevations along Interstate-95. The coastal ridge, a major geologic feature, significantly informs regional
drainage patterns throughout the City and greater South Florida. As a result,the downtown area generally slopes to the
Intracoastal Waterway on the east, and the medium-density engineered neighborhoods are divided by Interstate-95 and
this coastal ridge to the west.The DEM does not include bathymetry, which is typical of standard LiDAR datasets at this
time. In cases where bathymetric parameters were needed to simulate a water feature, Collective used Environmental
Resource Permits (ERPs) and other data sources to parameterize those necessary aspects of the City's ICPR model.
Page 22 of 129
111111111
City of Boynton Beach 2025 Watershed Master Plan
City of Boynton Beach i ° • '' Palm Beach County
�..
Watershed Master Plan k;
1,
Sources:
City Boundary-City of Boynton Beach A
DEM-Palm Beach County,Dewberry -`-a •)i. - City of Boynton Beach I'V
CBenkiy(2018) '-
Basemap-ESRI,USGS _ .Lake i, I .....
City of Boynton Beach Osbou'ne'-! --
Ground Surface Elevations(ft,NAVD88) --'""4:1 --
lr ,
s 1
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4 :j•er ^ -_: LEGEND
t `` '' `f L_ 1 City of Boynton Beach
.. )> .
'' - ,e,,,' I • Boynton DEM
'-' Elevation,ft(NAVD88)
High : 57.09
Lake (alb
' 10 - Low . -2.75
: = T �� , 1
0 Cs t N
1114 .lies
0 5,000 10.000 FeetA
Figure 5.Topography and Generalized Ground Surface Features of Boynton Beach, Florida
Page 23 of 129
City of Boynton Beach 2025 Watershed Master Plan
4.2 Soil Types (USGS Soils Data)
Digital soil data were obtained from the Natural Resource Conservation Service's (NRCS) Soil Survey Geographic
Database (SSURGO).The presence of certain soils can significantly impact hydraulic modeling results due to their unique
properties and characteristics. For example,the Basinger fine sand,found in slopes of less than 2 percent, is the most
prevalent soil group in the City and surrounding watershed (28.9%) and is known for its high permeability and low
retention capacity.This soil type allows water to infiltrate quickly, potentially leading to rapid groundwater recharge and
reduced surface runoff during rainfall events.
The second most prevalent soil group in the study area, St. Lucie-Paola-Urban land complex(20.2%),found in slopes of 0
to 8 percent, can influence water flow patterns and erosion potential within the watershed.The presence of this soil
type may affect the distribution of water across the landscape and contribute to sediment transport and deposition in
water bodies.Similarly, Immokalee fine sand (13.4%),found in slopes of less than 2 percent, can impact the movement
of water through the soil profile and influence groundwater levels with its low slopes and fine texture.This soil type may
affect the timing and magnitude of baseflow contributions to streams and rivers,as well as the availability of water for
vegetation and ecosystem health. Figure 6 illustrates the distribution of the different soil types across Boynton Beach
and the study area, and Appendix A includes more information on soil types and parameters.
Page 24 of 129
IIIIIIIIIIII
City of Boynton Beach 2025 Watershed Master Plan
i i r '; '0 Palm Beach County
City of Boynton Beach , .% \-, i
• Watershed Master Plan
Souses
,: City Boundary-City of Boynton Beech l� C 11
SSURGO Soil Data USGS NRCS(2022) f�n t. f"!
Basemap-SSRI,USGS = 'fr:n. ! 1 'ake ,' , City of Boynton Beach'
City of Boynton Beach ea. - - -
-URG05oilData rs[O f I'
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Ds 2 tt
[ 5000 1000055M
Figure 6. City of Boynton Beach SSURGO Soil Map Units (NRCS, 2022)
Page 25 of 129
111111111111
City of Boynton Beach 2025 Watershed Master Plan
4.3 Impervious Surface
An impervious area layer was generated using several Geographic Information Systems (GIS) and desktop techniques.
The building footprint shapefile was retrieved from the SFWMD data catalog and reviewed to confirm that the building
footprints reasonably represent actual conditions based on aerial imagery. Building footprints were used to represent
the building locations and impervious surfaces provided by residential and commercial developments.
A polygon layer that includes parking lots was developed by extracting the relevant land uses from the SFWMD 2022
Land Use Land Classification dataset.The land use types in this dataset that contain large parking lot areas include
commercial, parking lots, mobile home parks, office buildings, non-professional service buildings, multi-story, churches,
supermarkets, office buildings, non-professional service buildings, airports (private or commercial), bus terminals,
marine terminals, piers, marinas, and county property (other than public schools, colleges, and hospitals), including non-
municipal government. Wetland and greenery were removed from the resulting polygons because they are generally not
considered impervious for this analysis.
Roadways were also considered impervious surfaces and therefore are included in the impervious area shapefile
generated for Boynton Beach. A roadways shapefile provided by the City was used as the basis for the impervious
roadway layer. To supplement the shapefile, the major roads, state roads, and county roads feature datasets were
obtained from the Florida Department of Transportation (FDOT) open data catalog.The 2021 roadways dataset was
retrieved from the Palm Beach County GIS data catalog. The polyline datasets provided by FDOT and Palm Beach County
were converted to polygon layers.These layers were combined with the layer provided by the City to best represent the
existing roadway network within Boynton Beach. To better represent the width of roadways and represent their
impervious areas, the following interior buffers were applied to each dataset:
1. FDOT State Roads— 150 feet
2. FDOT County Roads—100 feet
3. FDOT Major Roads—65 feet
4. Palm Beach County Roads—20 feet
The road and parking lot polygons were combined with the building footprints layer, resulting in the total impervious
area. Because inaccuracies are present in the input datasets, making all corrections necessary to perfectly match the
current aerial imagery would not be feasible within the scope of the project. Nevertheless, the resulting coverage should
be a more accurate representation of impervious areas than land use-based estimates. Figure 7 shows the resulting
impervious layer.
Page 26 of 129
IIIIIIIIII
City of Boynton Beach 2025 Watershed Master Plan
j Palm Beach County t - ` r- .� ' '
�." Y City of Boynton Beach
z oke
;.:,7
Watershed Master Plan
&bour ` ,:.•
t r. -- rt� Sources:
l City,'Boynton Beach , �. s F : City Boundary-City of Boynton Beach
F t ..
�: , Impervious Areas-CWR(2024)
n3ra • ±x � easemap-ESRI,USGS
aigia
j F FF" City of Boynton Beach
+ , F .., !4a° ,l ,. it -, l Impervious Areas
4M1 (4 R
I l Lake Wonth2
f, Lagoon
ti
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�- LEGEND
I _ _ — ' -- City of Boynton Beach
,';. ` r - Impervious Areas
r :R ..
.$ �f
1 2 N
C 5.000 10000 Feet
Figure 7. Impervious Surface near and within the City of Boynton Beach
Page 27 of 129
City of Boynton Beach 2025 Watershed Master Plan
4.4 Wetlands and Natural Areas
With its extensive canal network and the Intracoastal Waterway, numerous wetlands are present throughout the City.
Along the Intracoastal Waterway is a significant area classified as 'Estuarine and Marine Deepwater' with areas of
'Estuarine and Marine Wetlands.' West from the coast are several large lakes to the north and south of the City,
including the previously mentioned Lakes Osborne and Ida.These natural areas act as important components of
stormwater management, providing valuable ecosystem services such as flood mitigation, water filtration, and habitat
preservation. The City is highly developed, so most of the other freshwater ponds and wetlands within the project area
are within engineered neighborhoods or golf courses, reducing the volume and velocity of water entering canals and the
City's drainage system during a storm. Figure 4 provides a visual reference for the locally maintained natural and
conservation areas.
According to the Florida Natural Areas Inventory (FNAI) (2023), many major natural areas, managed at a federal or state
level, are to the north and west of the City. Areas such as the Arthur R. Marshall Loxahatchee National Wildlife Refuge
managed by the US Fish and Wildlife Service,the Everglades managed by the National Park Service and partner state
agencies such as the Florida Department of Environmental Protection (FDEP), and the Francis S.Taylor Wildlife
Management Area managed by the Florida Fish and Wildlife Conservation Commission serve as an important
component of the larger hydrological system in Florida. These areas act as a natural reservoir to regulate water flow,
store excess rainfall, and recharge groundwater supplies. Within and closer to City limits, Boynton Beach has eight
locally managed natural areas, mostly to the east near the Intracoastal Waterway:
• High Ridge Scrub Natural Area
• Hypoluxo Scrub Natural Area
• Rosemary Scrub Natural Area
• Galaxy Sand Pine Natural Area
• Ocean Ridge Hammock Park
• North Ocean Ridge Mangroves Natural Area
• Ocean Ridge Natural Area
• Seacrest Scrub Natural Area
These natural areas play a critical role in maintaining the ecological balance of the region, supporting biodiversity, and
preserving important wetland habitats. The interconnectedness of these natural areas with the broader hydrological
system underscores their importance in maintaining a healthy and functioning watershed in Boynton Beach. Figure 8
shows the larger natural areas inland from Boynton Beach.
Page 28 of 129
City of Boynton Beach 2025 Watershed Master Plan
,.....0,...•,•-4:•-•- ,_- •,k. .
City of Boynton Bead= * ." Palm Beach County
Watershed Master Plan `� tv `�
Sources F.-. ,: } ...
City Boundary-City of Boynton Beach
Florida Natural Areas Inventory-Palm Beach
County(2023)
Basemap-ESR,USGS c-.t..t
'-.4c::..-).,
,-,, '-.3.,' y '
.'.-i'
"
'; . POA 1 e;r� Cityof Boynton Beach
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F Fran Reich, , .,.el'.':,.-L :� _,
PreserveE to-` " - • I City of Boyriton Beach
ve"f.des&Fra i >r�� �- .I Conservation Land Owner
S. Taylor Wildlife �' "
%,, y Federal
Management Area
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1r State
■
xs 3 to N 1
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n.000 so,000r-eet
Figure 8. Florida Conservation Lands—Florida Natural Areas Inventory(FNAI, October 2023)
Page 29 of 129
City of Boynton Beach 2025 Watershed Master Plan
4.5 City Stormwater Inventory and Infrastructure
The City includes an extensive network of stormwater infrastructure linked to secondary features, primarily those
managed by LWDD and primary features managed by SFWMD. FDOT and other entities also manage infrastructure
within the City limits, including private and County infrastructure.
For this study, the City provided a baseline stormwater inventory of hydraulic features. The City's consulting engineer
also compiled relevant district and state inventories to evaluate the performance of this infrastructure according to the
objectives of this project. Some of the engineered neighborhoods within the City contain outfalls that generally
discharge into SFWMD and/or LWDD systems during larger storm events. Many engineered communities within and
connected to the City also include essentially "zero discharge" systems that discharge via exfiltration systems. In these
systems, treated stormwater is discharged to groundwater when favorable conditions exist (i.e., when the water table is
low enough for this to occur).
The consultant team assembled a geodatabase of the hydraulic features that were critical for the completion of the
City's ICPR model.The geodatabase focused primarily on City stormwater assets and critical features owned and
operated by other critical parties such as SFWMD, LWDD, and FDOT. Key attributes compiled within the geodatabase
included applicable diameter, pipe material, inverts/key elevations, structure type, and pipe length. Owner was also
included as an attribute to describe the party responsible for the hydraulic feature. A geodatabase was delivered to the
City that includes additional information regarding the relevant existing hydraulic inventory at a District, County, and
City level.
Stormwater infrastructure generally includes stormwater pipes, manholes, drainage structures, and occasionally
stormwater pumps. Stormwater inventory GIS files provided by the City and SFWMD ERP plan sets were the primary
sources of stormwater infrastructure data. These sources were supplemented by desktop evaluations using 2021 aerial
photogrammetry and engineering judgement. The Engineer-of-Record visited structures and model locations as needed
to verify desktop evaluations.
In some cases, data provided directly by SFWMD and LWDD were used to supplement modeling efforts. Both parties
cooperated with the City in providing this information, and the data were handled on a case-by-case basis.
As a result of this study, the City's stormwater infrastructure database was markedly improved. At the outset of the
study, the City had a simple GIS geodatabase that included limited infrastructure with limited elevation data (and other
data necessary to manage and model the City's stormwater system). At the conclusion of this study,the City now has a
detailed and modern geodatabase that can serve as the foundation of various projects for the City. Collective estimates
that over 2,233 features were added to the City's stormwater geodatabase as a result of this project.
Table 1 summarizes the stormwater inventory by the City. Figure 9 spatially displays the City Stormwater Inventory,
including SFWMD ERP permits—additional permits were used for model parametrization than those included in the ERP
spatial dataset provided by the SFWMD and presented in Figure 9.
Page 30 of 129
City of Boynton Beach 2025 Watershed Master Plan
Table 1.City of Boynton Beach Stormwater Inventory Summary
Stormwater Asset
Total Number of Number of Assets by Owner
Assets City County LWDD State Private
Stormwater Pipes 3,485 1,448 401 8 148 1,348
Stormwater Manholes 832 327 140 0 211 110
Stormwater Outfalls 521 146 26 1 10 300
Stormwater Catch
4,259 1,358 447 1 264 1,992
Basins
Page 31 of 129
111.111111
City of Boynton Beach 2025 Watershed Master Plan
'' City of Boynton Beach +; , , -
. ' Palm Beach County ,
i
Watershed Master Plan ` z,.
1 Sources.
City Boundary-City of Boynton Brach --
Major Real Palm Beach County(2023) 111-yr
Canes-SFWMD AHED(2021) +l� "3•;
Stormwater opera's-city of Boynton Beach a+ ° E ' _e 'r'� i C;t of Boynton Beach n
Slormwater MH-Gty or Boynton Beach Y y
Slamwamn CP-Cityof Boynton Beach \ _
Stormwater Pipet-City of etymon Bead' � +� o'•- a �i: -t
Stormwater Retention Area-City or Boynton Beach " _ °:�
.q r=te. '"" '
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4 t s , f/, k LEGEND
• _ it i_ , ! ---,Pr.-__ ci City of Boynton Beach
—��� - • Stormwater Manholes
r o
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Figure 9. City of Boynton Beach Stormwater Inventory and SFWMD ERPs
Page 32 of 129
City of Boynton Beach 2025 Watershed Master Plan
4.6 Locations of Critical Facilities, Cultural/Historical Resources, and Other Places of Interest
Figure 10 illustrates some of the important places of interest in and around the City. Please see Appendix B,Table 1 for
a summary of other spatial information collected from the Florida Geographic Data Library(FGDL),such as historical and
cultural building locations and public facilities such as schools and fire stations.
Page 33 of 129
City of Boynton Beach 2025 Watershed Master Plan
T r�.,i 2x
City of Boynton Beach - `' ° !f, 1, \ • Palm Beach County
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Watershed Master Plan " a ti \ �„ ^�
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Figure 10. City of Boynton Beach—Other Areas of Interest (FGDL, 2023)
Page 34 of 129
MEM
City of Boynton Beach 2025 Watershed Master Plan
4.7 Vulnerable Areas and Their Descriptions
Based on the Federal Emergency Management Agency (FEMA) Preliminary Map Services for Palm Beach County's Digital
Flood Insurance Rate Map (DFIRM) (January 3, 2023), Figure 11 shows the flood map panels for the City and surrounding
area. Several areas of the City are classified as an area of minimal flood hazard. However, the land on either side of the
Intracoastal Waterway is classified as a coastal high hazard zone (AE zone). Along the E-4 Canal through the center of
Boynton Beach are pockets of areas that have a 2% annual chance of flood hazard in the coastal floodplain.
The City of Boynton Beach participated in in the Coastal Resilience Partnership of Southeast Palm Beach County's
Multijurisdictional Climate Change Vulnerability Assessment (CCVA) in 2021 and 2022 (Coastal Resilience Partnership,
Climate Change Vulnerability Assessment Update). The Vulnerability Assessment provided a baseline understanding of
eight climate risks in the sub-region.The goal of the CCVA was to study and determine long-term resilience and
adaptation strategies for each participating jurisdiction and the greater sub-region.
The CCVA established baseline areas prone to flooding and found that the most vulnerable areas to climate change are
areas with aging infrastructure and critical facilities near waterbodies, both coastal and inland. The City is particularly
vulnerable due to its relatively low topography, with some areas experiencing elevations lower than King Tide flood
elevations.
As Figure 10 shows,the CCVA found that Boynton Beach's educational and government facilities are near waterbodies
and will require coordination with Palm Beach County to adapt drainage capacity in future years. The highest levels of
vulnerability and risk were found to be associated with rainfall-induced flooding. Based on Figure A2-1 in the CCVA,the
inland areas projected to be the most affected by a 100-year/24-hour storm in the year 2040 were along S. Congress
Avenue, between Boynton Beach Boulevard to the north and the SFWMD C-15 canal to the south. Flood elevations
reached as high as 16.6 feet NAVD88 in the simulations completed as part of the CCVA. A link to the electronic version of
the CCVA is provided in the Citations section of this report.
Page 35 of 129
IIIIIIIIIIII
City of Boynton Beach 2025 Watershed Master Plan
Palm Beach County
City of Boynton Beach
Watershed Master Plan - /
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City Boundary-City of Boynton Beach Sj.
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Page 36 of 129
City of Boynton Beach 2025 Watershed Master Plan
4.7.1 Areas Prone to Flooding (City-Identified)
The City provided historical flood complaints that were submitted by customers between January 2018 and June 2021.
The complaints included the name of the customer,the address, a brief description of the complaint, and the outcome.
Collective reviewed for relevancy and whether the complaint had since been addressed.The recent CDM Smith
evaluation of the downtown area was also considered in the model development's level of detail ("Stormwater
Evaluation Final Report"). Figure 12 shows both.
Page 37 of 129
IIIIIIIIIII
City of Boynton Beach 2025 Watershed Master Plan
City of Boynton Beach r " ,, ,,0,71,i, Palm Beach County
9 Zeit Watershed Master Plan at
Sources
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y fustomer Fbod.ng Complaints-City of Boynton a t,;cy(, SII
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Areas Prone to Flooding City of ,I..
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Page 38 of 125
11111.11
City of Boynton Beach 2025 Watershed Master Plan
4.8 Natural and Constructed Drainage Systems and Channels
4.8.1 Canals and Surface Water Features
SFWMD and Palm Beach County are the primary sources of existing wetlands, canals, and surface waters. The City also
included retention areas in their stormwater inventory data. Figure 9 provides drainage system information. Figure 13
shows the SFWMD inventory of canals and major structures.
The modeled major canal inventory includes:
• C-16 Canal (Boynton Canal). Flows west to east and discharges through the 5-41 structure operated by the
SFWMD to the Lake Worth Lagoon.
• E-4 Canal. North/south canal west of Interstate-95. The LWDD canals connect to the E-4 Canal.
• L-18 Canal. LWDD canal at the north end of the watershed. Flows east and connects to the E-4 Canal just south
of Lake Osborne.
• L-19 Canal. LWDD canal flowing east to the E-4 Canal.
• L-20 Canal. LWDD canal flowing east to the E-4 Canal.
• L-21 Canal. LWDD canal flowing east to the E-4 Canal.
• L-22 Canal. LWDD canal flowing east, then south connecting to the C-16 Canal.
• L-23 Canal. LWDD canal flowing east then piped to the C-16 Canal.
• L-24 Canal. LWDD canal flowing east to the E-4 Canal.
• L-25 Canal. LWDD canal flowing east to the E-4 Canal.
• L-26 Canal. LWDD canal flowing east to the E-4 Canal.
• L-27 Canal. LWDD canal flowing east to the E-4 Canal.
• L-28 Canal. LWDD canal flowing east to the E-4 Canal.
• L-29 Canal. LWDD canal flowing east,then south to the L-30 Canal.
• L-30 Canal. LWDD canal flowing east to the E-4 Canal at the north end of Lake Ida.
Page 39 of 129
IIIIIIIIIIII
City of Boynton Beach 2025 Watershed Master Plan
City•
of Boynton Beach jr.,(., u' ) \e„,,..t 114,,, Palm Beach County
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Figure 13. SFWMD Canals and Structures(AHED, 2021)
Page 40 of 129
City of Boynton Beach 2025 Watershed Master Plan
The SFWMD AHED assisted in developing the project because it provides a database of hydrographic data features and
serves as a system of record within the District.The AHED was reviewed, refined, and referenced against the City's
stormwater infrastructure.
4.9 Existing Regulations and Plans in Place for Reducing Flood Risks
The existing policy framework related to reducing flood risk is housed within the City's Comprehensive Plan, primarily
the Coastal Management Element and Stormwater Sub-Element for Utilities. Relevant goals, objectives, and policies
follow.Additionally, relevant provisions from the City's Code of Ordinances follow as well.
Comprehensive Plan.City of Boynton Beach
Related to the reduction of flood risk,the City has adopted numerous policies within the Comprehensive Plan (available
via the City's website). Several of these policies were recently adopted pursuant to the requirements for Coastal
Elements in Section 163.3178, Florida Statutes (Peril of Flood) amendment process. They include:
Coastal Management Element(20161
Objective 7.6:The City shall continue to assess the current and future risks to human life and property from floods and
other natural hazards in the coastal areas and implement development and redevelopment strategies that reduce such
risks.
Measurability:Map updates, vulnerability assessments
Policy 7.6.1: The City shall maintain and update as needed all maps--including FEMA flood zones and repetitive claim
maps, storm surge/Coastal High Hazard Area maps and sea level rise impact maps—identifying current and potential
future areas subject to high flood hazard.
Policy 7.6.2:The City shall continue to document and maintain maps of extreme high tides ("king tides"), more frequent
severe rainfall events and newly revealed areas at risk of flooding to efficiently target mitigation efforts.
Policy 7.6.3:The City shall continue to provide flood relief and cleaning operations to lessen the residents' hardship after
a major rainstorm and document the City's after-the-storm efforts to evaluate and recommend implementation of
minor improvements and projects to be included in the Capital Improvements Plan.
Policy 7.6.4:The City shall continue to utilize the Future Land Use Map and the recommendations of the Community
Redevelopment Area Consolidated Plan as the basis for development and redevelopment.The siting, design and
construction of structures shall be consistent with regulations contained in the 5th Edition of the Florida Building Code
and the City Flood Prevention Code as amended from time to time.
Policy 7.6.5:The City shall manage its planning, regulatory and utility services to steer future population concentrations
away from the Coastal High Hazard Areas (CHHA),which is defined as the area below the elevation of the category 1
storm surge line as established by a Sea, Lake,and Overland Surges from Hurricanes (SLOSH) computerized storm surge
model.
Policy 7.6.6:The City shall not approve any increases in hotel/motel beds and residential densities in the Coastal High-
Hazard Area that would increase evacuation times above the 16 hours level of service for out-of-county hurricane
City of Boynton Beach 2025 Watershed Master Plan
evacuation for a category 5 storm event as measured on the Saffir-Simpson scale as provided in Section 163.3148(9)(a),
F. S.
Policy 7.6.7: By 2017,the City shall amend Land Development Regulations to prohibit hospitals, congregate living
facilities for persons with special needs, nursing homes, and the like from locating within Coastal High-Hazard Area and
FEMA-defined Special Flood Hazard Area, and also encourage such existing facilities to relocate to safer locations within
the City.
Policy 7.6.8: Redevelopment of existing dwelling units located in the Coastal High-Hazard area is prohibited unless an
engineering study supports that the redevelopment can occur in a safe manner when considering building construction,
design, siting and future storm events.
Policy 7.6.9:The City shall limit public expenditures in the Coastal High Hazard Area or flood-prone areas by restricting
expansion/improvement of the existing utilities except for improvements necessary to (1) correct current deficiencies;
(2) serve planned redevelopment pursuant to the CRA Community Redevelopment Plan; or(3) improve environmental
quality.
Policy 7.6.10:The City shall require that any construction activities seaward of the coastal construction control lines
established pursuant to Chapter 161.058, F.S. be consistent with the statutory provisions.
Policy 7.6.11:The city shall continue to revise building codes and land development regulations to enhance flood
mitigation measures in vulnerable areas to reduce future risks associated with high tide events, storm surge,flash
floods,stormwater runoff, and the related impacts of sea level rise. In these areas,the City shall require vulnerability
reduction measures for all new construction, redevelopment and infrastructure such as additional hardening, higher
floor elevations or incorporation of natural infrastructure for increased resilience.
Policy 7.6.12:The City shall consider, whenever feasible, purchasing properties in areas most vulnerable to destructive
storm surges for recreational uses and open space.
policy 7.6.13: Rise in sea level projected by the federal government(National Oceanic and Atmospheric Administration)
shall be taken into consideration in all future decisions regarding the design, location, and development of infrastructure
and public facilities in the potentially affected areas.
Objective 7.7:The City shall continue to apply the best planning and engineering practices in development to attenuate
and mitigate future flood events and modify the Land Development Regulations and other relevant regulatory
documents as needed.
Measurability: Update of the Flood Prevention Code, number of new storm water projects funded
Policy 7.7.1: By the end of 2017,the City shall further update its 2010 floodplain ordinance (Flood Prevention Code)for
consistency with the 5th edition of the Florida Building Code and also ensure that all future modifications of the flood-
resistant construction requirements in the Flood Prevention Code continue to be consistent with,or more stringent
than, requirements of the Florida Building Code and applicable flood plain management regulations set forth in 44 C.F.R.
part 60.
Page 42 of 129
•
City of Boynton Beach 2025 Watershed Master Plan
Policy 7.7.2: The City shall continue to upgrade its stormwater infrastructure through drainage improvements,
installation of tidal backflow preventers, and seawall repair in addition to sustainable flood management actions such as
installation of bioswales, recharge through drainage wells, use of pervious pavement, maintenance of natural preserves
areas and protection of tidal beaches that will stand the test of time and be adaptable to future climate changes.
Policy 7.7.3:The floodplain administrator/building official shall review all permit applications to determine whether
proposed development sites will be reasonably safe from flooding. If a proposed development site is in a flood hazard
area, all site development activities, (including grading, filling, utility installation and drainage modification), all new
construction and substantial improvements shall be designed and constructed with methods, practices and materials
that minimize flood damage and that are in accordance with the city Flood Prevention Code.
Policy 7.7.4: The City shall continue to participate in the National Flood Insurance Program's Community Rating System
(CRS) administered by the Federal Emergency Management Agency (FEMA)to reduce flood losses and achieve flood
insurance premium discounts for their residents.
Objective 7.8:The City shall continue to provide for the local implementation of the County Emergency Preparedness
Plan with respect to residential notification, evacuation and City management techniques, with particular emphasis
towards the City's multi-family and mobile home areas through an interlocal agreement, and to encourage public
participation in the planning process.
Measurability: Ongoing coordination with the Palm Beach County Division of Emergency Management.
Policy 7.8.1:The City shall establish and maintain procedures to maintain local emergency services personnel familiarity
with Palm Beach County's adopted Emergency Preparedness Plan.
Policy 7.8.2: The City shall continue to participate in all countywide emergency preparedness preparation and practice
sessions.
Policy 7.8.3:The City shall provide input to the County's informational program which identifies the location and
magnitude of the coastal area population requiring assistance in evacuation.
Policy 7. 8.4:The City shall continue to participate in the Palm Beach County Hazard Mitigation Working Group (HMWG)
and to adopt the HMWG pertinent recommendations on hazard mitigation.
Policy 7.8.5:The City shall participate in a long-term, countywide, comprehensive shelter program coordinated with
public, private, non-profit organizations to ensure adequate shelter space is available for the long-term needs of the City
and the County.
Objective 7.9: The City shall continue the implementation of its Climate Action Plan, revised in December 2015, which
will include a study aimed at exploring options for establishment of Adaptation Action Area(s).
Measurability:Adaptation Action Area Study funded and initiated by end of 2018. AAA areas established by 2020.
Policy 7.9.1: By the year 2018,the City shall initiate a study to evaluate options to establish Adaptation Action Area(s)
pursuant to Chapter 163.3177, F.S. for coastal areas that experience flooding due to extreme high tides and storm
surges and that are vulnerable to rising sea level. The study will identify portions of the City where the need to improve
Page 43 of 129
City of Boynton Beach 2025 Watershed Master Plan
resilience is the highest and prioritize those areas for adaptation measures and funding of infrastructure improvements.
The study shall consider the areas that:
1. Are below, at, or near the average water level
2. Have a hydrological connection to coastal waters
3. Are designated as evacuation zones for storm surge
4. Are otherwise impacted by climate-related drainage/flood control.
Policy 7.9.2:The City shall partner/coordinate on adaptation activities and access to technical assistance and support
with all relevant partners, including:
1. Southeast Florida Regional Climate Change Compact
2. FDOT and other agencies that plan for, or own, operate and maintain public infrastructure within, or crossing areas
identified for adaptation
3. Adjacent local governments if such areas extend beyond the City limits
Policy 7.9.3: By the end of 2017,the City shall integrate its Climate Action Plan into elements of the Comprehensive Plan
as appropriate.
Utilities Element/Stormwater Management Sub-Element(Amended 20201:
Goal 3B:The City of Boynton Beach will secure, maintain, and finance adequate stormwater drainage facilities to provide
protection from flooding to prevent degradation of the quality of receiving waters, and to meet the requirements of
designated land uses.
Objective 3B.1 The City of Boynton Beach will continue to require and enforce standards of the South Florida Water
Management District and the Lake Worth Drainage District such that sufficient stormwater drainage facilities to address
existing deficiencies, minimize damage to public and private property, protect surface and groundwater quality and
quantity, and meet future needs are constructed and maintained in the City limits.
Measurability:Number of storm water drainage facility improvements made consistent with the objective.
Policy 36.1.1:The City shall enforce the adopted Level of Service Standard for drainage facilities requiring designs for a
3-year storm for the duration of the time of concentration of the watershed.
Policy 3B.1.2:The City shall construct new stormwater drainage facilities to eliminate deficiencies in the existing system-
if they become necessary. Facilities and projects needed will be specified in the stormwater basin plans.
Policy 3B.1.3:The City shall continue to enforce the land development regulations requiring the provision of adequate
stormwater drainage facilities in all land use and zoning decisions.
• All new development must meet South Florida Water Management District and Lake Worth Drainage District, or
City of Boynton Beach requirements for drainage facilities,whichever is more stringent.
Page 44 of 129
City of Boynton Beach 2025 Watershed Master Plan
• First floor flooding will be minimized by requiring that first floor elevations be set at, or above,the level of the
100 Year Flood Elevation
Policy 3B.1.4:The City shall continue to maintain stormwater drainage plans for the various stormwater basins to
identify and prioritize needs for expansion, replacement, and improvement to the stormwater system in the City.
Policy 3B.1.4:The City shall continue to maintain stormwater drainage plans for the various stormwater basins to
identify and prioritize needs for expansion, replacement, and improvement to the stormwater system in the City.
Policy 3B.1.5:The City will continue to coordinate with the Lake Worth Drainage District,the South Florida Water
Management District and Palm Beach County, as appropriate, on stormwater planning and management issues.
Policy 36.1.6:The City shall consider that drainage problems that cause street flooding,first floor structure flooding, or
traffic hazards will be priority projects and will be corrected as soon as funds become available.
Policy 36.1.7:The City shall not consider nuisance flooding as a priority drainage problem.
Policy 36.1.8: The City shall continue to provide a regular program of street cleaning.
Policy 3B.1.9:The City shall continue to clean miscellaneous facilities such as open ditches on an as needed basis.
Policy 3B.1.10: Drainage facilities owned by the South Florida Water Management District, Lake Worth Drainage District,
Florida Department of Transportation, or Palm Beach County that are in the City shall continue to be maintained by the
entity that owns them.The City will inform and cooperate with these entities as they repair or maintain their structures
in the City.
Policy 36.1.11:The City shall consider priorities for replacement,correcting existing deficiencies, and providing for
future needs.The need shall be determined by the City through a stormwater basin planning process.The priorities shall
be reflected in the Capital Improvements Element such that the improvements of highest priority shall be implemented
first, in order to provide for public health and safety,the adopted level of service, and operational efficiency.
Policy 36.1.12:The City shall continue to implement the strategies of the stormwater basin plans.
Objective 3B.2:The City of Boynton Beach will protect the quality and quantity of surface water and groundwater from
direct discharges of stormwater runoff.
Measurability:Number of improvement projects to prevent direct discharges of storm water runoff.
Policy 36.2.1:The City shall continue to meet land development regulations requiring water quality criteria for drainage
discharge set by the South Florida Water Management District and Lake Worth Drainage District.
Policy 36.2.2:The City shall continue to monitor its drainage charge system fees to ensure that new approved
development will pay its fair share of existing or planned capital facilities in accordance with the Stormwater Basin Plans.
Policy 3B.2.3: The City shall continue to enforce the land development regulations requiring that rainwater runoff be
minimized by maximizing infiltration by percolation into grassy swales, medians,golf courses, landscape areas,
nurseries, parks, lawns, et cetera.
Page 45 of 129
City of Boynton Beach 2025 Watershed Master Plan
Policy 36.2.4:The City shall continue to enforce the land development regulations requiring exfiltration drains be used
to alleviate small drainage problems in currently developed areas whenever possible.
Policy 36.2.5:The City shall continue to enforce the land development regulations requiring that all new development
plans must have approval or letter of exemption from the South Florida Water Management District and Lake Worth
Drainage District.
Policy 3B.2.6:The City shall continue to enforce the land development regulations requiring that all new development
will have approved detailed construction plans that include drainage facilities and identify all nearby areas of
groundwater recharge.
Policy 3B.2.7:The City shall continue to enforce the land development regulations requiring that retention and/or
detention in new developments will conform to the water quality requirements of Chapter 62-25, Florida Administrative
Code.
Policy 38.2.8:The City shall continue to enforce the land development regulations requiring that the stormwater storage
and recharge potential of properties shall be retained and enhanced,where possible.
Policy 3B.2.9:The City shall continue to enforce the land development regulations requiring that post development
runoff volumes shall not exceed pre-development runoff volumes,wherever possible.
Objective 3B.3: Development and redevelopment will be encouraged in areas presently served adequately by existing
drainage facilities in order to prevent urban sprawl.
Measurability:Number of infill development and redevelopment projects approved consistent with the objective.
Policy 38.3.1:The City shall continue to enforce the land development regulations maintaining a stormwater charge
system so that new development will pay for its fair share of existing or planned capital facilities in accordance with the
Stormwater Basin Plans.
Objective 3B.4:The stormwater drainage regulations contained in the City's land development code shall provide for
protection of the City's natural drainage features,which are the Atlantic Ocean,the Intracoastal Waterway, and Lake
Worth; and shall ensure that future development utilizes stormwater management systems compatible with the City's
stormwater management sub-element.
Measurability:Number of development orders or building permits denied for inconsistency with the objective.
Policy 36.4.1:The City shall continue to enforce the land development regulations requiring that new developments
manage runoff from a three-day, 25 year storm.
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Code of Ordinance.City of Boynton Beach
Sec. 26-141. Discharge of stormwater and other unpolluted drainage.
(a) No person shall discharge or cause to be discharged any stormwater,surface water,ground water,
uncontaminated cooling water or unpolluted industrial process waters to the sanitary sewer.
(b) Stormwater and all other unpolluted drainage shall be discharged to those sewers as are specifically designated as
storm sewers, or to a natural outlet approved by the proper city or county official. Industrial cooling water or unpolluted
process waters may be discharged on approval of the Utilities Director to a storm sewer or natural outlet.
Pursuant to Chapter 26,Water, Sewers and Utilities,Article VI. Stormwater System Sec. 26-300. Purpose and intent.
The purpose of this article is to promote the health, safety and general welfare of the inhabitants of the City of Boynton
Beach.This article is intended to comply with federal and state law and regulations regarding water quality.
Sec. 26-302. Industrial activity.
(a) General prohibitions [Reserved.]
(b) Specific prohibitions. By adoption of industrial activity stormwater regulations or by issuance of industrial activity
stormwater permits, or both,the director may impose reasonable limitations as to the quality of stormwater(including
without limitation the designation of maximum levels of pollutants) discharged into the stormwater system from sites of
industrial activity.Any promulgation of such regulations and issuance of permits by the director shall be in accordance
with applicable law.
(c) Administrative orders.The director may issue an order to any person to immediately cease any discharge
determined by the director to be in violation of any provision of this article, or in violation of any regulation or permit
issued hereunder.
(d) NPDES permits.Any person who holds a national pollutant discharge elimination system (NPDES) permit shall
provide a copy of such permit to the director no later than the later of: sixty(60) calendar days after the effective date
of this article or sixty(60) calendar days after issuance.
Sec. 26-303. Illicit discharges.
(a) General prohibitions. Except as set forth under subsection (c)of this section or in accordance with a valid NPDES
permit,any discharge to the stormwater system that is not composed entirely of stormwater is prohibited.
(b) Specific prohibitions.Any discharge to the stormwater system containing any sewage, industrial waste or other
waste materials, or containing any materials in violation of federal, state, county, municipal or other laws, rules,
regulations,orders or permits, is prohibited.
(c) Authorized exceptions. Unless the director determines that it is not properly managed or otherwise is not
acceptable,the following discharges are exempt from the general prohibition set forth under subsection (a)of this
section:flows from firefighting, water line flushing and other contributions from potable water sources, landscape
irrigation and lawn watering, irrigation water, diverted stream flows, rising groundwaters,direct infiltration to the
stormwater system, uncontaminated pumped groundwater,foundation and footing drains,water from crawl space
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City of Boynton Beach 2025 Watershed Master Plan
pumps,air conditioning condensation, springs, individual residential car washings,flows from riparian habitats and
wetlands, and dechlorinated swimming pool contributions.
(d) Illicit connections. No person may maintain, use or establish any direct or indirect connection to the stormwater
system that results in any discharge in violation of this article.This prohibition is retroactive and applies to connections
made in the past, regardless of whether made under a permit, or other authorization, or whether permissible under
laws or practices applicable or prevailing at the time the connection was made.
(e) Administrative order.The director may issue an order to any person to immediately cease any discharge, or any
connection to the stormwater system, determined by the director to be in violation of any provision of this article,or in
violation of any regulation or permit issued hereunder.
Sec. 26-304. Spills and dumpings.
(a) General prohibitions. Except as set forth under section 26-303(c)of this article with a valid NPDES permit,any
discharge to the stormwater system that is not composed entirely of stormwater is prohibited.
(b) Specific prohibitions.Any discharge to the stormwater system containing any sewage, industrial waste or other
waste materials, or containing any materials in violation of federal, state, county, municipal, or other laws, rules,
regulations, orders or permits, is prohibited.
(c) Notification of spills.As soon as any person has knowledge of any discharge to the stormwater system in violation
of this article, such person shall immediately notify the director by telephoning 407-738-7460, and if such person is
directly or indirectly responsible for such discharge,then such person shall also take immediate action to ensure the
containment and cleanup of such discharge and shall confirm such telephone notification in writing to the director at
City of Boynton Beach, 124 East Woolbright Road, Boynton Beach, Florida 33435,within three (3) calendar days.
(d) Administrative order.The director may issue an order to any person to immediately cease any discharge or
connection to the stormwater system, determined by the director to be in violation of any provision of this article, or in
violation of any regulation or permit issued hereunder.
Sec. 26-305. Enforcement.
(a) Injunctive relief.Any violation of any provision of this article, or of any regulation or order issued hereunder, shall
be subject to injunctive relief if necessary to protect the public health, safety or general welfare.
(b) Continuing violation.A person shall be deemed guilty of a separate violation for each and every day during any
continuing violation of any provision of this article, or of any regulation or permit issued hereunder.
(c) Enforcement actions.The director may take all actions necessary, including the issuance of notices of violation,the
filing of court actions and/or referral of the matter to the local code compliance board to require and enforce
compliance with the provisions of this article and with any regulation or permit issued hereunder.
Sec. 26-306. Inspections and monitoring.
(a) Authority for inspections. Whenever necessary to make an inspection to enforce any of the provisions of this
article,or regulation or permit issued hereunder,or whenever an authorized official has reasonable cause to believe
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City of Boynton Beach 2025 Watershed Master Plan
there exists any condition constituting a violation of any of the provisions of this article, or regulation or permit issued
hereunder, any authorized official may enter any property, building or facility at any reasonable time to inspect the
same or to perform any duty related to enforcement of the provisions of this article or any regulations or permits issued
hereunder; provided that:
(1) If such property, building or facility is occupied,such authorized official shall first present proper credentials and
request permission to enter; and
(2) If such property, building or facility is unoccupied, such authorized official shall make a reasonable effort to
locate the owner or other person having charge or control of the property, building or facility, and shall request
permission to enter.
Any request for permission to enter made hereunder shall state that the owner or person in control has the right to
refuse entry, and that in the event entry is refused,the authorized official may enter to make inspection only upon
issuance of a search warrant by a duly authorized magistrate. If the owner or person in control refuses permission to
enter alter such request has been made,the authorized official is hereby authorized to seek assistance from any court of
competent jurisdiction in obtaining entry. Routine or area-wide inspections shall be based upon such reasonable
selection processes as may be necessary to carry out the purposes of this article, including but not limited to random
sampling and sampling in areas with evidence of stormwater contamination, non-stormwater discharges, or similar
factors.
(b) Authority for monitoring and sampling. Any authorized official may establish on any property such devices as are
necessary to conduct sampling or metering of discharges to the stormwater system. During any inspections made to
enforce the provisions of this article, or regulations or permits issued hereunder,any authorized official may take any
samples deemed necessary.
(c) Requirements for monitoring.The director may require any person engaging in any activity or owning any
property, building or facility(including but not limited to a site of industrial activity)to undertake such reasonable
monitoring of any discharge(s)to the stormwater system and to furnish periodic reports.
Part III, Chapter 4, Land Development Regulations,Article VIII, Utility and Infrastructure Design Standards, Sec.3
Standards, G. Drainage,Stormwater, and Wastewater Management.
1. Drainage.
a. Applicability.Any proposed building addition, swimming pool, patio, driveway, deck, or similar structure or
improvement that decreases the permeable land area in excess of eight hundred (800) square feet on any parcel shall
provide a professionally prepared drainage plan.
In addition,an adequate storm, surface and ground water drainage system, including necessary ditches,canals,swales,
percolation areas, detention ponds, storm sewers, exfiltration trenches, drain inlets, manholes, headwalls, endwalls,
culverts, bridges and other appurtenances shall be required in all subdivisions.
Any development that is part of an overall master stormwater plan may have the provisions of this paragraph waived
at the sole discretion of the City Engineer or designer.
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City of Boynton Beach 2025 Watershed Master Plan
b. Design Standards. Construction plans and certified drainage design data includes but is not limited to the
method of control of storm water and groundwater; drainage plan; existing water elevations; recurring high water
elevations; proposed design water elevations; drainage structures; canals; ditches; and any other pertinent information
pertaining to the system. Provide for drainage of lots, streets, roads and other public areas including surface waters
which drain into or through the property.The drainage design must provide adequate surface water drainage of
naturally occurring or existing adjacent contributory areas. All drainage areas shall be designed in accordance with the
Engineering Design Handbook and Construction Standards or latest supplement thereof. Where additional ditches and
canals are required to accommodate contributory surface waters, right-of-way shall be dedicated for future needs. An
exception exists where a developer may excavate or open sufficient capacity to provide for existing drainage needs
whenever the developed or undeveloped status of adjacent areas so warrants, subject to approval by the City Engineer.
c. Drainage Easement. Drainage easements shall be provided where necessary at a width adequate to
accommodate the drainage facilities in accordance with the Engineering Design Handbook and Construction Standards.
Utility easements and drainage easements shall be separate unless otherwise approved by the Director of Utilities and
the City Engineer. Where easement crossings occur, drainage easements shall take precedent.
2. Stormwater Management. When approved positive drainage is not available, on-site containment of stormwater
run-off shall be provided by the developer. Details of the on-site system shall be approved by the City Engineer.
a. Applicability. Storm water shall be treated in the development by providing on-site percolation and/or
detention or any appropriate treatment technique acceptable to the South Florida Water Management District
(SFWMD).
b. Design Standards. Rainfall runoff, surface waters, and groundwaters shall be managed in developments to
optimize water quality and maximize percolation and detention to promote the re-use of this resource. All
stormwater/wastewater areas shall be designed in accordance with the Engineering Design Handbook and Construction
Standards or latest supplement thereof. However, pervious areas shall be sodded and irrigated unless other landscaping
is approved by the Director of Planning and Zoning.
Additional criteria can be found in Chapter 5 of the City's Engineering Design Handbook and Construction Standards
(2021).1
Finally, Article VII establishes the City's Stormwater Utility Fee structure to levy and collect stormwater assessments for
capital expenditures. Section 26-408 states that the stormwater utility enterprise fund includes the following purposes
for the program.There shall be established a stormwater utility enterprise fund for the deposit of all fees and charges
collected by the stormwater utility. These funds shall be for the exclusive use of the city's stormwater management
utility including, but not limited to, the following:
(1) Stormwater management services, such as studies, design, permit review, plan preparation and development
review.
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City of Boynton Beach 2025 Watershed Master Plan
(2) Operation, maintenance, repair and replacement of the stormwater collection, storage, treatment and
conveyance infrastructure.
(3) Project costs related to constructing major or minor structural improvements to the stormwater-related
infrastructure as provided in the city-wide stormwater management plan.
(4) Administrative costs associated with the management of the stormwater utility fee. A maximum of$2,000 may
be transferred to the general fund annually for administrative costs.
(5) Debt service financing of stormwater-related capital improvements defined in the city-wide stormwater
management plan.
(6) Funding of studies including water quantity and quality monitoring, aerial photography, and geotechnical work
associated with the planning of the stormwater-related infrastructure.
The City also maintains a Downtown Stormwater Improvement Watershed Fee pursuant to Sec. 26-406. A full version of
Article VII is attached as Appendix D.
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City of Boynton Beach 2025 Watershed Master Plan
4.10 Inventory of Data Availability
Datasets required for compliance with the Florida's HMGP for completing this WMP were discussed in previous sections.
Appendix A and B provide a more detailed description of the sources and processing of the base data reviewed and
analyzed in model development. Other critical datasets not previously mentioned are briefly described below. This
section provides a brief review of some of the other supporting datasets used to develop the City's ICPR model and this
report.
4.10.1 Land Use and Land Classification
Digital land use data were obtained from the SFWMD (2017-2019) and reviewed for the Florida Land Use, Cover, and
Forms Classification System (FLUCCS) codes and polygons, and areas were manually updating due to development or
change in land use as necessary using 2021 aerial photogrammetry published by Palm Beach County.The majority of the
Boynton Beach watershed is classified as residential, medium-density and residential, high-density (33.3%and 22.3%of
the total watershed area, respectively).
Land use and land classifications are used to identify areas of high imperviousness, which contribute significantly to
stormwater runoff and increase flood risk. For example, residential, medium-density and residential, high-density areas
are likely to have a higher percentage of impervious surfaces and directly connected impervious surfaces compared to
other land use types such as wetlands and rural areas.The distribution of impervious areas influences the design of
stormwater management infrastructure, such as retention ponds, swales, and drainage systems,to mitigate the adverse
effects of urbanization on water quality and quantity. Figure 14 shows the current land use across Boynton Beach and
the study area, and Table 2 summarizes the City by land use.
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City of Boynton Beach 2025 Watershed Master Plan
'91▪11LOiflli.•LB�.�,,-ay:•eI .•a,r. - _ Pis iv.4 F. I .-
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Figure 14. Boynton Beach Study Area Land Use and Land Classification (SFWMD, 2017-2019)
Page 53 of 129
MEM
City of Boynton Beach 2025 Watershed Master Plan
Table 2: Land Use(2017-2019)for Boynton Beach Study Area (SFWMD, Quality Controlled by Collective Water
Resources, LLC)
Land Use Land Use Description Total Area per Land Use Percent of Watershed
Code (Acres) (%)
1210 Residential, Medium Density 5137.3 33.3%
1310 Residential, High Density 3433.7 22.3%
1810 Recreational 1770.9 11.5%
1400 Commercial and Services 1598.7 10.4%
5300 Reservoirs 567.4 3.7%
8140 Transportation 524.4 3.4%
5110 Streams and Waterways 473.8 3.1%
1110 Residential,Low Density 472.2 3.1%
1700 Institutional 427.2 2.8%
1550 Industrial 228.3 1.5%
1900 Open Land 201.2 1.3%
4110 Upland Coniferous Forests 174.6 1.1%
4340 Upland Mixed Forests 106.0 0.7%
2520 Specialty Farms 67.1 0.4%
4200 Upland Hardwood Forests 52.8 0.3%
3200 Upland Shrub and Brushland 39.9 0.3%
6120 Wetland Hardwood Forests 39.8 0.3%
8330 Utilities 34.1 0.2%
6410 Vegetated Non-Forested Wetlands 17.2 0.1%
3300 Mixed Rangeland 16.0 0.1%
2410 Nurseries and Vineyards 12.6 0.1%
8200 Communications 11.0 0.1%
5200 Lakes 7.6 0.0%
2230 Tree Crops 6.7 0.0%
Total Area of Boynton Watershed(Acres): 15,420.7
4.10.2 Groundwater
Depth to groundwater data were obtained from the SSURGO dataset by soil map unit. Within the SSURGO dataset,
depth to the water table was determined based on the weighted average of all component soils for June through
October.
The depth to groundwater is essential for assessing the overall water balance within the watershed and parameterizing
some basic elements of the ICPR model. Groundwater levels influence the surface water flow,groundwater recharge
rates, and availability of water for various uses such as irrigation, drinking water supply, and ecosystem support.
Additionally,groundwater depths impact the hydraulic conductivity of the subsurface materials,which affects the
movement of water through the soil and underlying aquifers.
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City of Boynton Beach 2025 Watershed Master Plan
Variations in groundwater depths can lead to changes in flow patterns, groundwater seepage into surface water bodies,
and potential flooding risks. The depths to groundwater ranged from 0 inch (map unit MUKEY 1407286, Okeelanta
muck, drained, frequently ponded, 0 to 1 percent slopes) to 79.1 inches (map unit MUKEY 1407289, Palm Beach-Urban
land complex, 0 to 8 percent slopes). Please refer to Figure 15.
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City of Boynton Beach 2025 Watershed Master Plan
Ci of Boynton Beach1
41k,„,,." Palm Beach County
Watershed Master Plan a r—,...1,.;.„4-4 —
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SSURGO Soil Data-USG5 NRCS NM) Ft.
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City of Boynton Beach City of Boynton Beach
Depth to Water Table by SSURGO Soli MUKEY M 6-,ourne --
II IS ' ir I bilk
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-ke Depth to Water Table(inches)
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Figure 15. Depth to Water Table, inches(USGS NRCS,2022)
Page 56 of 129
City of Boynton Beach 2025 Watershed Master Plan
4.10.3 Environmental Resource Permits
ERPs and Consumptive Use Permits (CUPs) within the study's watershed were retrieved from SFWMD and reviewed for
inclusion in model parameterization. ERPs are required for stormwater projects including building dams or reservoirs,
dredging and filling in wetlands or surface waters, and providing stormwater containment and treatment—among other
types of projects. The stormwater information in ERPs can be important to modeling. In this case, outfall locations in
ERPs were used to confirm other data sources. Table 3 summarizes ERPs, including the degree of data confidence.
Appendix E provides detailed list of ERPs. CUPs can provide useful model information regarding groundwater and
surface water. In this effort, CUPs were of limited value because the focus is primarily on stormwater, but the data were
consulted to see if it would provide value in terms of soils parameters for the ICPR model.
Table 3: Study Area ERPs and CUPs Summary(SFWMD)
Permit Type Total Number of Number of Permits Number of Permits Number of Permits
Permits with 'As-Built' Plans with 'Approved' with Soil Data
Plans
Environmental Resource Permits I 291 8 200 11
Consumptive Use Permits I 1992 0 I 129 I 2
4.10.4 National Oceanic and Atmospheric Administration (NOAA) Historical Trends and SLR Estimation
Historical trends at the nearest long-term tidal gauge to Boynton Beach (Lake Worth Pier, No. 8722670) between 1970
to 2022 indicate the relative sea level has risen an average of 4.03 mm/year (NOAA, "Tides and Currents").This is
equivalent to a rise of 1.32 feet in 100 years. Figure 16 shows this linear trend. The data from the NOAA provide valuable
insights into the long-term trends of SLR, which is essential for planning and designing stormwater management systems
that can effectively mitigate the risks associated with coastal flooding and inundation.
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City of Boynton Beach 2025 Watershed Master Plan
8722670 Lake Worth Pier, Florida 4.03 +/- 0.53 mm/yr
0.60
—Linear Relative Sea Level Trend
0.45 - —Upper 950/0 Confidence Interval
—Lower 95" Confidence Interval
Monthly mean sea level with the
0.30•- average seasonal cycle removed
0.15 - - - - - - -
M -
in
Y0.00, ',li/II
-0.15•-
-0.30•-
-0.45•-
-0.60•
1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 2020
Figure 16. Lake Worth Pier SLR (1970-2022, NOAA)
4.10.5 Southeast Florida Climate Compact
The Southeast Regional Florida Climate Change Compact is a joint effort between Broward, Miami-Dade, Monroe, and
Palm Beach Counties to coordinate regional greenhouse gas emissions reductions, implement adaptation strategies, and
build climate change resilience across the Southeast Florida region(Coastal Resilience Partnership, Final Project Report).
As a municipality within Palm Beach County,the City of Boynton Beach is an active participant in the Compact.
The Compact played a crucial role in shaping the City's WMP by providing essential climate assessment tools and data
for informed decision-making. The recent update to the 2019 Unified Sea Level Rise Projection from the Compact was
referenced and refined for the City. Metrics such as tidal datums and storm surge were identified and updated, as
necessary, for this study.
Tidal datums were developed from SLR estimates and King Tide elevation data from the Compact (Coastal Resilience
Partnership, Climate Change Vulnerability Assessment Update). These King Tide elevations were adjusted to determine
the Mean Higher High Water (MHHW) elevations. The 2021 CCVA used the Lake Worth Pier gauge and defined the
Adaptation Action Elevation (AAE) to be 2.2 feet NAVD88. Using that 2.2 feet NAVD88 elevation,the MHHW was
adjusted from the current MHHW with an additional 0.5 foot of SLR between 1992 and 2020. Table 4 shows the
projected MHHW and mean sea level for 2040, 2070, and 2100 at NOAA Intermediate-Low and Intermediate-High
scenarios.
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City of Boynton Beach 2025 Watershed Master Plan
Table 4:Adjusted MHHW for NOAA Lake Worth Pier Gauge
- moi
NOAA INT-LOW NOAA INT-HIGH
Current 2040 2070 2100 2040 2070 2100
Threshold (2020)
(ft)
Current+ Current+ Current+ Current+ Current+ Current+
4"(ft) 11"(ft) 17" (ft) 10"(ft) 33" (ft) 67"(ft)
98%Higher High Water
(AAE) 2.2 2.6 3.2 3.6 3.0 5.0 7.8
Mean Higher High Water 1.1 1.5 2.1 2.5 1.9 3.9 6.7
Mean Sea Level -0.4 0.0 0.6 I 1.0 0.4 2.4 5.4
Storm surge flood elevation calculations were also consistent with the Compact's Unified Sea Level Rise Projection
methodology(Coastal Resilience Partnership, Climate Change Vulnerability Assessment Update).The Base Flood
Elevations(BFE)from the 2017 FEMA Flood Insurance Study(FIS) Report were adjusted to account for SLR since 1977
and were used as the starting elevations for the FIS.The accepted rate of rise for the CCVA was 3.81 mm/year
(0.0125 ft/year),which yielded the 0.5 foot of rise between 1977 and 2020. Table 5 summarizes storm surge elevations
used in this study.
Table 5:Storm Surge Minimum and Maximum Elevations with SLR from 2017 NOAA Intermediate-Low and
Intermediate-High Curves(ft, NAVD88)
NOAA INT-LOW NOAA INT-HIGH
Current 2020 BFEs 2040 2070 2100 2040 2070 2100
(2017 BFE+0.5 ft)
(ft, NAVD88) Current+ Current+ Current+ Current+ Current+ Current+
4" (ft) 11" (ft) 17" (ft) 10" (ft) 33" (ft) 67" (ft)
Minimum 6.5 6.9 7.5 7.9 7.3 9.3 12.1
Maximum 13.5 13.9 14.5 14.9 14.3 16.3 19.1
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City of Boynton Beach 2025 Watershed Master Plan
4.11 Studies of Existing Development and the Potential Impact of Redevelopment
Another critical type of data that was collected for this study involves investigating existing development and planned
redevelopment.Three previous studies investigated existing development and the potential impacts of redevelopment:
• Florida Storm water Regulations:The Statewide Stormwater Rule Ratification Bill (SB 7040)was signed into law
(Chapter 2024-275, Laws of Florida)on June 28, 2024,with immediate effect. Under the new rule (Chapter 62-
330, Florida Administrative Code [FAC]), applicants for stormwater management systems will continue to have
the flexibility to choose from a range of design options, including a variety of best management practices,when
designing systems to meet the performance-based design criteria.The confluence of increasing water quality
regulation and onsite stormwater management with the related changes in quantities that will have to be
managed from changing environmental conditions should be viewed together to determine the ability of
stormwater regulations to manage drainage systems.
• Downtown Storm water Modeling Evaluation: In 1998, CDM Smith (then CDM)completed a Stormwater
Evaluation for the Downtown Watershed within the City of Boynton Beach. Given the age of that report and the
interest in redeveloping the Downtown Watershed, it was updated in 2023.This 2023 study was focused on
creating a thorough and modernized analysis of the Downtown Watershed and then evaluating several
alternatives to address flooding in areas that did not meet specific level of service criteria.The City is further
evaluating some of these alternatives, particularly given the new Stormwater Rule discussed above.The study
explicitly modeled several newer and pending developments throughout the watershed.The City's Storm Water
Management Model (SWMM) model was converted to an ICPR model. and many aspects of that analysis
informed this study. Figure 1-2 from that study, excerpted as Figure 17, summarizes both studies.
• Multi-Jurisdictional Climate Change Vulnerability Assessment(CCVA), Final Project Report: Boynton Beach fully
participated in two phases of comprehensive planning to assess the potential impacts of climate change on the
City and as part of the Coastal Resilience Partnership of Southeast Palm Beach County.The comprehensive CCVA
was published in July 2021, and an addendum was published in August 2022 to make the project compliant with
the FDEP Resilient Florida Program statutory requirements under Section 380.093, Florida Statutes. Notably,
extensive hydrologic and hydraulic(H&H) modeling and flood inundation mapping were completed as part of
this effort.Three flood threats were evaluated by professional engineers, including rainfall-induced flooding,
storm surge, and tidal flooding from SLR.The City created an extensive list of Adaptation Strategies to address
the climate threats that included structural and non-structural measures. Many of these strategies and the
findings of this study informed the methodology and findings of this WMP.The full report can be viewed here:
h ttps://discover.pbcoov.orq/resilience/Panes/Partnerships/CoastalResiliencePartnership.aspx
• San Castle, Lake Boynton Estates, and Chapel Hill Storm water Evaluation: In 2021, CDM Smith completed a
Stormwater Evaluation for three residential neighborhoods within the City totaling 972 acres.The study further
evaluated significant flooding caused by a series of storm events between September 25 through October 24,
2020. Based on the study recommendation,the City hired an engineer to conduct a more detailed evaluation
and subsequent design to mitigate flooding within the San Castle development.The project associated with San
Castle is expected to start construction in 2025-2026. Lake Boynton Estates and Chapel Hill were also further
evaluated by this project.All projects in this report need to be re-evaluated against the new treatment
standards that will likely be required by the new FDEP Clean Waterways Act Stormwater Rule promulgated in
2024.
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City of Boynton Beach 2025 Watershed Master Plan
Both San Castle and Lake Boynton Estates were discussed in detail as part of the City's Vulnerability Assessment and
the 2021 CDM Smith Study. Both were reviewed against the new Stormwater Rule and the watershed modeling
completed for this study.All three developments are included throughout this report.
Page 61 of 129
City of Boynton Beach 2025 Watershed Master Plan
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City of Boynton Beach 2025 Watershed Master Plan
5. Summary of ICPR4 Modeling
Collective used the datasets previously described in this WMP to develop a detailed one-dimensional ICPR version
4.07.08 model for the watershed that includes Boynton Beach and relevant adjacent connected watersheds (see Figure
18). All major boundary conditions and relevant subwatersheds for the C-16, E-4, and other LWDD canals are included in
the City's ICPR4 model. Several sets of hydrologic scenarios were prepared for Collective to use, including relatively
smaller and current storm events through large future scenarios. Pipes and control structures that significantly
contribute to the hydraulics within the watershed were included in the ICPR model.
The City's delineated watershed exceeds its municipal boundaries where it was deemed necessary, based on
engineering judgement, to model areas outside the City to adequately represent a reasonable and physically realistic
watershed boundary. Major roads provided the boundaries of the watershed north and west of the watershed. The total
area of the watershed is approximately 14,559 acres, which is 37% larger than the City's total area (10,601 acres).The
current conditions model was reviewed per datasets available as of 2023 (so the model is date certain through the end
of 2023). Figure 18 summarizes the study and model domain. Appendix A provides a more detailed description of the
modeling methodology and parameterization criteria. The following briefly summarizes the model parameterization.
Page 63 of 129
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Page 64 of 129
City of Boynton Beach 2025 Watershed Master Plan
5.1 Boundary Conditions and Model Datum
The Boynton Beach watershed boundary used for the model was delineated hydrologically and hydraulically and by the
City's jurisdiction.The Boynton Beach watershed is bounded to the east by the Intracoastal Waterway.The adjacent
barrier island which includes a very limited portion of the City-approximately 34 acres, Briny Breezes, Ocean Ridge, and
Gulfstream was not modeled in ICPR because it is not hydrologically connected via overland flow to the major City
watershed. Control structures along the major canals (e.g., C-16)were used to create boundary conditions.To the north,
the Boynton Beach watershed is bound by Hypoluxo Road,with a node placed to denote the inflows/outflows from Lake
Osborne.To the west, South Military Trail is generally used for the boundary.To the south,the L-30 Canal forms the
south boundary, and Lake Ida serves as a boundary condition for flows from and to the south.
The vertical datum used within the City's ICPR model is NAVD88.All data from the stormwater inventory, plans, permits,
etc. were converted to this datum where appropriate using a conversion factor of-1.54 feet. Collective heavily used GIS
throughout developing the model and moved data into and out of ICPR using a variety of methods(including the use of
geodatabases).
5.2 Hydrology
The City's model was divided into 747 basins. Nodes and links were also considered during the hydrologic model
development since they are closely tied to model performance and quality. Basin boundaries were reviewed in detail by
the Engineer-of-Record for conformance with topography and ERPs.
Green-Ampt methodology was used to quantify rainfall excess and infiltration.This method assumes homogeneous soil
with constant hydraulic conductivity, initial water content, and head at the wetting point.The Green-Ampt method was
ultimately chosen for this model because it is used for single rainfall events where evapotranspiration and unsaturated
gravity driven flow are insignificant.Another benefit of using Green-Ampt is that the depth to water table is a defined
parameter and can be adjusted for the future scenarios to simulate the rise in groundwater table as sea level rises for
the future scenarios.
5.3 Hydraulics
The model was parameterized to run over a wide variety of hydrologic conditions (both small and large storms).This
required widespread usage of overflow weirs to simulate overland flow. Larger pipes and structures that interconnect
basins are also represented in the City's ICPR model within the hydraulic simulations. For each scenario(storm and year)
the hydraulic model includes 1,064 nodes and 2,233 links. Figure 19 shows the ICPR model schematic. Boundary
conditions, including parameters related to groundwater,varied between design storms as well as current and future
conditions.
The flood protection level of service (FPLOS) model developed separately for SFWMD was used to develop boundary
condition data for:
• Lake Osborne (stages and flows)
• Lake Ida (stages and flows)
• C-16 west of Military Trail (flows only)
• L-19 west of Military Trail (flows only)
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EMIR
City of Boynton Beach 2025 Watershed Master Plan
• L-26 west of Military Trail (flows only)
• L-30 west of Military Trail (flows only)
5.4 Special Notes on the Boynton Beach Watershed and Boundary Conditions
Throughout the modeling, Collective noted that this system is particularly sensitive to the actions of SFWMD and LWDD,
statutory entities that the City has no authority to control or mandate operational criteria. Despite these legal
structures,the entities have a positive and close working relationship. Collective used data from each responsible entity
to create the model for this project and believes this report and analyses to be a sound representation of the watershed
over these four planning horizons and many storm events.
However, some issues were present during the parameterization of existing conditions and became more challenging
during future conditions modeling. As a result, Collective documented challenges because they will persist and impact
the City's ability to manage stormwater moving forward. Specifically, these challenges are:
• Development of boundary conditions.
• Differences between the City and SFWMD models: For this WMP, Boynton Beach must simulate different
scenarios than those created by SFWMD's FPLOS program to an appreciable degree to comply with the
requirements placed on them by FEMA, the International Organization for Standardization (ISO), FDEP, and
others.The models are also different—ICPR for the City and DHI Software for SFWMD. As a result, significant
translation was necessary.At a minimum, it would be very helpful if SFWMD ran simulations required for both
the CRS Program and Resilient Florida, in addition to any simulations they may need for their purposes. In turn,
the City can run simulations and pass data and information back to SFWMD and LWDD. Ideally, a feedback loop
would exist between the SFWMD model and City model.
• Future depth to groundwater elevations accuracy: For future updates to the WMP, running the SFWMD's FPLOS
model(s) to provide depth to groundwater elevations for the future scenarios so that the Green-Ampt ICPR4
parameters in local ICPR models can be more accurately adjusted would be ideal.
• Inflows and outflows are impacted by outside entities. The flood stages in the City highly depend on the
controlled outflows to the Intracoastal Waterway, and the inflows from LWDD and SFWMD canals form the west
side of Military Trail. Again, the City does not have authority over these entities for operational criteria. Using
the FPLOS model(s) to optimize the operation of LWDD and SFWMD structures to minimize flood impacts to the
City and surrounding areas while also meeting any environmental requirements would be beneficial.
• LWDD has numerous permitted outfalls from developments to the LWDD canals. Over 70 permitted outfalls to
LWDD canals are simulated in the City's ICPR model.These LWDD permits for these outfalls require permittees
to obtain permission from LWDD before opening overflow structures to discharge more than their normal,
permitted rates.The model was simulated to reflect that these outfalls did not open their overflows. Performing
simulations to identify the impact of all overflows being opened before a major storm event may be beneficial.
This is a model sensitivity, and actual condition that should be discussed by both the City and LWDD. This study
indicated that this condition will need to be actively managed in future years.
• The City lacks current calibration data from active stage recorders for the canal system within the City. Besides
the SFWMD monitored S-41, no active stage recorders are within the City. Additional temporary stage recorders
provided data for several years but are not currently active. Additional stage/flow recorders at the following
locations would be helpful to properly simulate the flows and stages:
Page 66 of 129
City of Boynton Beach 2025 Watershed Master Plan
o Lake Ida (former temporary station) near the outflow from the L-30
o E-4 at L-18
o E-4 at C-16
Collective also notes that many of these concerns are not unique to Boynton Beach and recommends that the City,
SFWMD, and LWDD continue to coordinate using H&H models to simulate watersheds in South Florida for various
purposes.
Page 67 of 129
City of Boynton Beach 2025 Watershed Master Plan
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5.5 General Notes on Errors, Warnings, and Production Runs
The 500-year storm event was used to remove all errors and relevant warnings from the model before production runs
commenced for existing conditions. Future conditions modeling used the 2100 100-year storm event scenario to check
for errors and warnings. Hydrographs were reviewed by the Engineer-of-Record in detail before proceeding with
production runs.The model was not classically calibrated because all potential calibration locations were adjacent to
SFWMD infrastructure which offers no information on the City's system internal to the watershed (and these areas are
not the focus of this study). However,the model results were compared to historical flood reports throughout the City
and were in excellent agreement.The results of the modeling efforts are described throughout the remainder of this
report.
6. Summary of ICPR4 Modeling for Current Conditions
The City's ICPR model was used to simulate several design storms of differing durations for both existing and future
conditions.The design storm rainfall volumes are consistent with the SFWMD ERP manual's standard temporal spread of
72 hours. Model results for current conditions were evaluated to establish the existing drainage system's response to
each storm.
6.1 Design Storms for Current Conditions
Table 6 shows the selected design storm rainfall depths and durations for current(2025)conditions. Most of the
precipitation estimates are from the NOAA's Atlas 14.The 2-year, 24-hour and 5-year, 24-hour precipitation estimates
were used to interpolate the 3-year, 24-hour design storm because there is no 3-year recurrence interval in the NOAA's
Atlas 14.Appendix B includes the ERP Handbook's Isohyetal Maps for each of these design storms and the NOAA's Atlas
14 precipitation frequency estimates for Boynton Beach. Collective reviewed both data sources and determined that the
NOAA rainfall depths provided more recent and robust information regarding the City's hydrology.The use of NOAA
data agrees with the majority of H&H models being built for non-ERP purposes throughout Florida. USGS also
recommends using NOAA Atlas 14 with rainfall change factors,which were used to simulate future conditions.
Table 6:Selected Design Storm Depths(in inches)and Durations for Current Conditions
Recurrence Interval, Duration Precipitation Estimate(inches)
3-year, 24-hour 6.11
10-year, 24-hour 8.87
25-year, 24-hour 11.40
25-year, 72-hour 13.30
100-year, 24-hour 15.80
100-year, 72-hour 18.20
500-year, 72-hour 25.10
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City of Boynton Beach 2025 Watershed Master Plan
6.1.1 Detailed Tailwater Assumptions (Mean Tide, Mean High Water, etc.) for Current Conditions
Tailwater assumptions for the study were consistent with the methodology used and accepted by the Southeast Florida
Regional Climate Change Compact (Coastal Resilience Partnership, Final Project Report). For current conditions, the 98-
percentile Higher High Water (AAE)for 2020 of 2.2 feet NAVD88 was used. Also, the MHHW level was calculated to be
1.1 ft NAVD88. Please see Appendix A for more details regarding these estimates.
6.2 System Response to the Current 3-, 10-, 25-, and 100-Year Storm Events
The City has completed multiple flood studies over the past 30 years. These assessments demonstrate a general
consensus regarding the areas with the highest flooding potential within the City. However, this study aims to
supplement previous work and provide a helpful watershed-wide assessment.
This WMP's purpose is to provide a tool that can be used in decision-making to reduce flooding from future conditions,
which can include development/redevelopment, climate change, and SLR.This WMP will be used to meet one of the
requirements within the CRS program to attain a CRS Class 4 designation and to develop a comprehensive response plan
to a variety of natural disasters.To date, the following information is available regarding storm events and system
response:
• The City is highly vulnerable to LWDD and SFWMD activities due to the interconnectedness of the City's
watersheds.The area between Interstate-95 and the E-4 Canal generally drains to the E-4 Canal.The watershed
west of the E-4 Canal generally drains to one of the 14 LWDD and SFWMD canals west to east to the E-4 Canal
(as listed in Section 4.8.1). LWDD and SFWMD have major control structures within the City's extents that
manage outflows to the Lake Worth Lagoon and inflows from west portions of the LWDD and SFWMD canals.
The City's flooding extent varies significantly because of the different topography from west to east. The
engineered neighborhoods on the west side of the City generally experience less flooding than those to the east,
primarily because the west neighborhoods are designed and built under ERPs for the 25-year storm event.
Flooding extents increase significantly across the east portions of the City.The City is highly vulnerable to SLR
and storm surge east of Federal Highway, which is compounded with elevated risk of rainfall-induced flooding to
the west.
• Several portions of the City are more vulnerable to flooding than previously expected, primarily because FEMA
did not initially map these areas as high risk. Study results indicate that flooding for both the 25-year and 100-
year storm events are significant and generally City-wide. Furthermore, engineered neighborhoods to the west
(and even into the adjacent areas in unincorporated Palm Beach County) are subject to flooding in both current
and future conditions—to varying degrees.
Appendix G provides the floodplains for the 10-, 25-, 100-, and 500-year storm events. Appendix F provides the detailed
model output.
System response across all design storms is summarized below.
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City of Boynton Beach 2025 Watershed Master Plan
• As Table 7 shows, over 1,200 acres are within the floodplain for the 3-year/24-hour storm event. However, most
of this area consists of existing lakes and other waterbodies. Other predicted flooded areas include some low
roads and land in older parts of the City.
• For the 10-year/24-hour storm event,the flooded area within the City increases by about 500 acres.The
additional flooded area is mostly low roads serving the developments discharging to the LWDD canals.
• For the 25-year/24-hour storm event,the flooded area within the City increases by about 1,200 acres over the 3-
year storm. A significant portion of the additional flooded land is in the Leisureville area.This area is discussed in
Section 9.2.2.3 and is complicated both in terms of hydrology but also socio-politically.
• For the 25-year/72-hour storm event,the flooded area within the City increases by about 1,700 acres over the 3-
year storm.A significant portion of the additional flooded land is in the Leisureville area, but more significant
scattered flooding is likely in lower areas throughout the City.
• For the 100-year/24-hour storm event,the flooded area within the City increases by about 2,700 acres over the
3-year storm.The additional flooded area is along the E-4 Canal and other LWDD canals and scattered low areas
throughout the City. For larger storm events,the flooding extents and depths increase at these areas.
Table 7: Extent of Flood Inundation for Existing Conditions Across All Design Storm Events
Total Flooded Total Flooded Area
Area Entire Flooded Area within Flooded Area within
Storm Event Watershed Within Entire City(acres) City(%)
(acres)
Watershed (%)
3-year/24-hour 1,784.7 12.3% 1,277.5 12.8%
10-year/24-hour 2,539.0 17.4% 1,770.3 17.8%
25-year/24-hour 3,570.4 24.5% 2,444.0 24.5%
25-year/72-hour 4,291.7 29.5% 2,979.8 29.9%
100-year/24-hour 5,715.2 39.3% 3,977.2 39.9%
100-year/72-hour 6,555.6 45.0% 4,719.4 47.4%
500-year/72-hour 8,660.8 59.5% 6,299.0 63.2%
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City of Boynton Beach 2025 Watershed Master Plan
7. Summary of ICPR4 Modeling for Future Conditions
The City of Boynton Beach is almost fully built out. This means that redevelopment will be the primary type of
development in the future.This section pertains to redeveloped conditions, future rainfall, and boundary conditions that
include future sea level rise.
7.1 Future Land Use/ Fully Developed Conditions
As described previously, SFWMD land use maps were refined and used in the hydrologic analysis. Of the 9,966 acres of
the City in the watershed, about 301 acres are undeveloped and may be considered developable for future scenarios.
The undeveloped land includes:
• FLUCCS 1900, Open Land
• FLUCCS 2230, Other Groves
• FLUCCS 3200, Upland Shrub and Brushland
• FLUCCS 3300, Mixed Rangeland
• FLUCCS 4110, Pine Flatwoods
• FLUCCS 4130, Sand Pine
As the City is nearly built out, future development activity will primarily consist of the redevelopment of existing
developed areas. The existing land use was compared to zoning and future land use data provided by the City to identify
areas where the land use changed under future conditions. The analysis identified 855 acres of land use changing from
existing to future conditions. This new development/redevelopment was assigned 2.5 inches of initial abstraction to
account for future water quality treatment requirements.
Within the refined future land, a higher regulatory standard occurs in areas that changed from less to more developed.
This change is appropriately considered due to the aforementioned 2024 Stormwater Rule and the steadily increasing
stormwater management requirements over the past 30 years.
Figure 20 shows future land use for the City of Boynton Beach.
Page 72 of 129
City of Boynton Beach 2025 Watershed Master Plan
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Page 73 of 129
City of Boynton Beach 2025 Watershed Master Plan
7.2 CRS-Compliant ICPR4 Model Run for 2100 using NOAA Intermediate-High
Collective completed a specific model run to comply with the CRS requirement to analyze 2100 conditions using the
NOAA Intermediate-High scenario.Appendix F provides the model results, and Appendix H contains the floodplains for
this scenario. As expected, model results showed significant inundation throughout the City for this scenario.
The following changes to the existing conditions model were made to simulate the future 2100 Intermediate-High
conditions:
• The future land use conditions described in Section 7.1 were applied to the basin hydrology.
• The 2100 Intermediate-High boundary condition (6.67 feet-NAVD) at the Intracoastal Waterway was used for
the tailwater elevations and to set initial elevations for nodes.
• The 2100 Intermediate-High boundary condition (6.67 feet-NAVD) was used to adjust the depth to groundwater
table values for the Green-Ampt soil infiltration methodology.
• The future 2100 rainfall volumes were applied to the hydrology (Section 7.3).
• The operational controls of the canals were not modified for future conditions.This is primarily due to the
unknown nature of future LWDD and SFWMD actions at this time.This assumption provides a conservative
approach from the City's perspective, but modeling the canal's operational controls is definitely a potential
future model update that might be advantageous for the City and regional agencies to undertake.
For this scenario,the infiltration capacity of the soils was greatly reduced due to the rising water table while the rainfall
volumes were greatly increased (factor of 1.73 for the 100-year/24-hour storm), which produced a vastly larger runoff
volume for the existing infrastructure to handle as compared to existing conditions.This resulted in the predicted
flooded area in the watershed and the City to increase from 39%to 60%from 100-year/24-hour existing conditions to
the 2100 intermediate-high 100-year/24-hour storm as shown in Appendix H.
Areas that tributary to the SFWMD and LWDD canals are the primary areas experiencing flooding.The model suggested
that significantly less flooding would occur on the east side of Interstate-95.
7.3 Future Rainfall
USGS provides change factors by duration, return period, and location that can be multiplied by NOAA Atlas 14
precipitation data to determine projected future rainfall.These change factors were applied to existing rainfall (see
Table 6)to determine future rainfall events.The USGS Atlas 14 station 90-0621 near the intersection of South Military
Trail and Palm Chase Drive in the City of Boynton Beach was used to determine the change factors.The USGS table of
change factors used was titled "Spreadsheet of quantiles of change factors at 242 NOAA Atlas 14 stations in Florida
derived from downscaled climate datasets considering only the best models, and the RCP8.5 and SSP5-8.5 future
emission scenarios"for 2040 and 2070.The 5-year, 24-hour change factor was used for the 3-year, 24-hour future
rainfall calculation because no change factor was available for the 3-year storm event.The 50th percentile change
factors were used for the 2040 and 2070 storm events.The change factor used for the 2100 storm events was the 2070
95th percentile change factor.Table 8 summarizes the USGS change factors used and future rainfall amounts.
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Table 8: USGS Rainfall Change Factors and Future Rainfall
2040 2070 2100
Storm Event Future Future Future
Change Change Change
Rainfall Rainfall Rainfall
Factor Factor Factor
(in) (in) (in)
3-Year/24-Hour 1.07 6.54 1.11 6.78 1.37 8.37
10-Year/24-Hour 1.10 9.76 1.17 10.38 1.49 13.22
25-Year/24-Hour 1.15 13.11 1.21 13.79 1.75 19.95
25-Year/72-Hour 1.24 16.49 1.32 17.56 2.19 29.13
100-Year/24-Hour 1.13 17.85 1.21 19.12 1.73 27.33
100-Year/72-Hour 1.20 21.84 1.29 23.48 2.19 39.86
7.4 System Response to the Future 3-, 10-, 25-, and 100-Year Storm Events
This study is being completed at a time of accelerated action by both local governments and state agencies to address
acute flooding and climate change.A concerted attempt was made to reasonably simulate future conditions within the
constraints of existing data and the timeline of this project.To date,the following information is available regarding
future storm events and system response as a result of this study:
• The City will continue to be highly vulnerable to LWDD and SFWMD activities due to the interconnectedness of
the City's watersheds. In particular,the outcome of the SFWMD's structural operations will be critical in terms of
flood mitigation throughout most of Boynton Beach.
• Particularly for larger storm events, stages/flows (in and out)from the north (Lake Osborne)and the south (Lake
Ida)greatly impact the stages in the E-4 Canal and all its tributaries in the study area.The outflow capacity of the
S-41 at the east end of the C-16 Canal limits the ability of the drainage network for the City to discharge
stormwater to the Intracoastal Waterway.
• The many developments along the LWDD and SFWMD canals have discharge structures designed and operated
for current conditions.These will need to be modified for future conditions to continue to provide the maximum
amount of flood protection practical.
Appendix F provides the detailed model output for all storms, and Appendix H contains the floodplains for future
conditions.
For the 10-year/24-hour storm,the flooded area within the City limits almost doubled; for the 100-year/72-hour storm,
the flooded area increased by almost 40 percent compared to existing conditions.The majority of the increased flooded
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City of Boynton Beach 2025 Watershed Master Plan
area occurred along the LWDD canals.Tables 9 and 10 summarize the extent of flood inundation for all future design
storms.
Table 9: Flood Extent for Future Conditions Within City Limits(by Acreage)for All Storm Events
Storm Event Existing(ac) 2040 IL(ac) 12040 PH(ac) 2070 IL(ac) 2070 IH (ac) 2100 IL(ac) 2100 IH (ac)
10-yr/24-hr 1,770.3 2,107.6 2,287.6 2,483.7 2,902.6 3,255.5 3,526.2
25-yr/24-hr 2,444.0 3,004.4 3,212.4 3,408.8 3,715.3 4,580.4 4,842.5
25-yr/72-hr 2,979.8 3,740.4 3,867.2 4,053.8 4,179.4 5,482.9 5,616.6
100-yr/24/hr 2,979.8 4,477.3 4,623.4 4,815.0 5,001.6 5,790.9 6,007.1
100-yr/72-hr 4,719.4 5,185.2 5,237.4 5,369.9 5,443.1 6,484.2 6,549.2
Table 10: Flood Extent for Future Conditions Within City Limits(by Percentage)for All Storm Events
Storm Event Existing(%) 2040 IL(%) 2040 IH (%) 2070 IL(%) 2070 IH(%) 2100 IL(%) 2100 IH(%)
10-yr/24-hr 17.8% 21.1% 23.0% 24.9% 29.1% 32.7% 35.4%
25-yr/24-hr 24.5% 30.1% 32.2% 34.2% 37.3% 46.0% 48.6%
25-yr/72-hr 29.9% 37.5% 38.8% 40.7% 41.9% 55.0% 56.4%
100-yr/24/hr 29.9% 44.9% 46.4% 48.3% 50.2% 58.1% 60.3%
100-yr/72-hr 47.4% 52.0% 52.6% 53.9% 54.6% 65.1% 65.7%
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City of Boynton Beach 2025 Watershed Master Plan
8. Results
8.1 Change in Runoff from Current to Future, Fully-Developed Conditions
Collective analyzed the change in runoff from current to future fully developed conditions for flooding impacts.Table 11
summarizes runoff results from the ICPR4 model. Within ICPR and for this analysis,rainfall excess volume is defined as
the remaining water after initial abstraction, evapotranspiration, and infiltration have been fulfilled.
As of 2024,the City is almost fully developed, so runoff is unlikely to change substantially between existing and future
conditions solely based on land use change.The percentage of runoff within the total outflow decreases for the 2040
Intermediate-High, 2040 Intermediate-Low, and 2070 Intermediate conditions for all storm events and the 2070
Intermediate-High conditions for the 25-year and 100-year storm events. However,the volume of runoff increases from
current to future conditions in all cases.
The increase in runoff volume is due to the increase in overall rainfall volume for future conditions (i.e.,the use of the
rainfall change factors).The lower runoff percentage of total outflow is likely because of redevelopment that aims to
reduce flooding impacts through reducing runoff.Table 11 provides an interesting and encouraging result of the study in
that it demonstrates the potential effectiveness in minor improvements in development and regulatory standards
throughout the watershed as climate change advances.
Table 11: Change in Runoff from Current to Future(Fully-Developed Summary)
Current 2040 IH 2040 IL 2070 IH 2070 IL 2100 IH
Condition 2100 IL Runoff
Storm Runoff Runoff Runoff Runoff Runoff
Runoff
Event
Acre-ft % Acre-ft % Acre-ft % Acre-ft % Acre-ft % Acre-ft % Acre-ft %
1
3-Year/
4,024 95.4 5,777 94.1 4,992 93.2 7,962 95.6 6,303 94.5 9,949 96.4 8,688 95.9
24-Hour
10-Year/
6,616 97.1 9,552 96.3 8,422 95.8 12,400 97.1 10,611 96.7 15,954 97.7 14,666 97.6
24-Hour
25-Year/
9,382 98.0 13,655 97.4 12,861 97.1 16,610 97.8 14,814 97.6 24,286 98.5 22,975 98.4
24-Hour
25-Year/
11,650 98.4 17,823 98.0 16,660 97.8 21,273 98.3 19,465 98.1 35,652 99.0 34,339 98.9
72-Hour
100-Year/
14,670 98.7 19,502 98.2 18,338 98.0 23,205 98.4 21,392 98.3 33,371 98.9 31,548 98.8
24-Hour
100-Year/
17,569 98.9 24,431 98.5 23,266 98.4 28,602 98.7 26,781 98.6 48,938 99.3 47,625 99.2
72-Hour
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City of Boynton Beach 2025 Watershed Master Plan
9. Strategy and Action Plan to Ensure that the Flood Hazard for the 3-, 10-, and
25-Year Events are Not Increased by Future Development
The project team collaboratively developed a suite of flood mitigation measures that are diverse in scope. These
measures can be applied equitably across the City.The measures are also supported by the scientific findings of this
WMP and previous City studies.This diverse menu of strategies ensures that the City is more resilient as changes in the
watershed take place. When combined, implemented, and monitored correctly,these strategies will likely provide
significant and synergistic flood relief in future conditions for storm events up to and including the 25-year storm
event. Because this study also included information up to the 100-year storm event for current and future conditions,
the City can expect some relief in larger storm events by applying these measures. However,given the size of these
events and the hydrography of South Florida,the City cannot completely mitigate larger storm events.
Furthermore, compared to other South Florida communities, Boynton Beach has an unusually high level of network
canals that weave through the City that are controlled by SFWMD and LWDD—and much of the City was developed
before modern stormwater permitting and engineering/development requirements. Due to this issue, the City has an
exceptionally high level of complexity in future years in terms of effectively mitigating floods. The actions of these
external agencies will affect most of the City's watershed and will be discussed throughout the rest of this WMP.
Furthermore, and primarily due to this issue, the City cannot address the majority of flooding via piecemeal engineering
projects (as is the practice of some other Florida communities via traditional stormwater master planning). Because of
all of these constraints, a scientific, adaptive,watershed, and all-solutions approach is likely the only way the City can
effectively address flooding.
Given the significant challenges facing the City, a strong and diverse portfolio of flood mitigation measures is
recommended.These measures include traditional engineering, sustainable and nature-based solutions, and policy
(regulatory) considerations—among other non-structural initiatives. The City prioritizes long-term sustainability and
considered issues related to energy consumption and pollutant reduction as part of developing these measures.
9.1 Regulations
From a regulatory perspective, the City has somewhat consistent, but different levels of service (LOS) described
including the 3-year event (involving time of concentration),the 3-day 25-year event, and a harmonization of City,
SFWMD, and LWDD standards for stormwater design. The City would benefit from a clarification of one concise and
consistent standard to be carried through its development regulations and consideration of future conditions from an
SLR tidal flooding perspective and reflecting future rainfall conditions that will produce higher rainfall volumes over
time. In addition, the reference to time of concentration should be removed because of the likely inconsistency that
parameter can produce in drainage designs across the City.
The City should also consider that its primary mode of future compliance will include redeveloping parcels and having
the ability or requirement to retain more stormwater onsite, lessening the burden on the City's and region's systems.
Finally, the City will have to consider its shoreline resilience and fill policies for public and private shorelines to build
resiliency to increased tidal flooding. A recommended strategy includes retaining water onsite to address increasingly
,age 78 of 129
City of Boynton Beach 2025 Watershed Master Plan
challenging future environmental flood conditions. These challenges will only be addressed through continued and
enhanced coordination among the City, SFWMD, and LWDD.This is especially important recognizing that the SFWMD
and LWDD's structural and upstream discharge operations directly impact the City's stormwater system.
9.2 Structural Controls for Water Quality and Quantity
Structural controls are physical features installed to control stormwater runoff and prevent pollutants from entering
waterways and sensitive natural areas.The City already encourages and mandates certain structural controls, as
referenced in Section 4.9.The State of Florida recently passed new stormwater regulations with additional requirements
for structural controls for stormwater treatment. All future City projects will likely require higher levels of treatment
compared to pre-2024 conditions.
Additional recommendations are provided below that will help reduce the volume of runoff generated and the
associated peak flow, with an emphasis on treatment for projects where Collective identified this to likely be an issue.
Generally speaking, water quality should be a part of every flood mitigation project within the City. This may not be
possible in a few cases due to space and/or hydrologic constraints.
Most of the City west of Interstate-95 discharges to the C-16 Canal or LWDD Canals (L-18 to L-30). The C-16 Canal is
controlled by a large, gated structure (S-41) at the east end of the canal, shortly before it discharges to the Lake Worth
Lagoon. The E-4 Canal flows north to south through the City about 0.75 mile west of Interstate-95. The E-4 Canal
receives flow from Lake Osborne to the north and at the south part of the watershed flows south to Lake Ida at the
outfall of the L-30 Canal. The E-4 Canal is connected to the C-51 watershed to the north and the C-15 watershed to the
south. Both of these watershed outfall canals have their own major SFWMD structures controlling their flows and
stages. How these major outfall structures at the C-51, C-16, and C-15 are operated has a significant impact on the
performance of the canals (and therefore flooding) within the City's watershed.
The developments west of Interstate-95 generally have gated structures to control their discharge to the SFWMD and
LWDD canal system.These developments included stormwater management systems carefully operated and provide a
level of flood protection based on the current operation of the S-41 structure. However, under future scenarios the
operation of this (and the C-51 and C-15) structure will need to be modified to maintain desired water levels in the
canals. Additionally, changes in the operation of the C-16 may necessitate changes to the control structures of 80+
developments that discharge to this canal system within the City.
9.2.1 Ongoing (2025-2026) Projects
The City commenced many flood mitigation projects in recent years. Many of these projects completed the planning
and/or design phases in 2024 and are currently under construction or will be in the near future with the exception of
Lakeside Garden, which was completed in September 2024. Figure 21 and the following section summarize these
projects.
Page 79 of 129
City of Boynton Beach 2025 Watershed Master Plan
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Page 80 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.1.1 Areas Recently Studied by the City/CDM Smith
Section 4.11 highlighted two recent studies completed by CDM Smith.The City is moving forward with the
results of both studies, as Section 4.11 previously discussed.The study results study reinforced the importance
of this CDM Smith study regarding flood mitigation in some key areas throughout the City. Some refinements
and detailed results (per this study)are further discussed in Section 9.2.2.
9.2.1.2 Lakeside Gardens (Current Improvement Project Location #2 in Figure 21)
This project is a complete neighborhood improvement project between N. Federal Highway and the Intracoastal
Waterway, north of the C-16 Canal.The project consists of replacing water main,the sanitary sewer system, and
the drainage system including stormwater pipes; installing new valley gutter; installing a new outfall; and
enhancing existing outfalls to optimize capacity and functionality.The project also included swales and driveway
improvements.This project will substantially assist in flood reduction for a residential community.This project
was completed in September 2024.
9.2.1.3 Coquina Cove(Current Improvement Project Location#3 in Figure 21)
This project is in design and consists of a neighborhood improvement project.The project includes replacing
water and sewer mains and improving swales and driveways.This project will also include installing a new 24-
inch outfall.This project is primarily geared toward assisting with tidal flooding but may also provide some relief
for rainfall-induced flooding near the Intracoastal Waterway. Construction for this project is expected to start in
2025 and be completed in 2026.
9.2.1.4 Heart of Boynton (Current Improvement Project Location#4 in Figure 21)
This project includes reclaimed,sewer, and stormwater improvements as part of the large residential and
commercial redevelopment.The "Heart of Boynton" project is within the Martin Luther King Jr. Boulevard
corridor in northeast Boynton Beach. Improvements within this area in response to flooding include checking
and constructing swales and exfiltration trenches to increase storage and reduce flooding in the area.This
project is projected to be completed in 2026.
9.2.1.5 Installation of Pollutant Control Boxes
In recent years,the City installed several projects that involved reducing flooding and installing pollutant control
boxes. Figure 22 shows these locations.
Page 81 of 129
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Page 82 of 129
City of Boynton Beach 2025 Watershed Master Plan
'1.2,2 Recommended Structural (Infrastructure) Projects
Study results indicated that the City faces several complex challenges related to flooding given the roles of SFWMD, LWDD,
and new state stormwater regulations. Figure 23 shows the final areas of concern from the study. Additional survey,
geotechnical testing, and detailed engineering would be necessary to fully design and permit these projects. Although
many of these projects focus on infrastructure (both green and gray), they involve significant coordination efforts with
external agencies and the public. Modern stormwater engineering should be conducted in this manner, and this
integration is particularly important for the City of Boynton Beach given the vulnerabilities and constraints it faces both
physically and socio-politically.
The study validated the projects that the City has underway (Section 9.2.1) because modeling showed significant flooding
in all of those areas. This modeling effort also identified five additional major areas of concern that were previously
undocumented. Collective reviewed those current projects and provided some refinements and suggestions in this
section. New projects are also provided in this section. Flooding was evaluated based on the physical reality of the issues
present, although some areas of concern relate to issues that are somewhat to wholly outside the City's control. Some of
these constraints include:
• Tidal flooding—It is difficult for the City to fully address this type of flooding as part of a stormwater study.Areas
that interconnect with where tidal flooding and/or storm surge may occur are noted in this section. Engineering
recommendations are made based on the information generated by this study and engineering judgment.
• Infrastructure managed by parties external to the City (primarily FDOT, SFWMD, and LWDD) — Appreciable
flooding interconnects with canals managed by SFWMD and LWDD.The City should share the study results with
all parties. It is also difficult for the City to ensure structures are maintained and operated properly in gated
communities to the west.
• FDOT roadways—Many FDOT roadways in the City are subject to flooding. Recommendations were not made for
those roadways, but Figure 23 shows the major areas flagged. Namely,these roadways are (based on the study's
10-year storm event indicating more than 6 inches of flooding at the crown of road) Congress Avenue, Military
Trail, Gateway Boulevard, Federal Highway, Lawrence Road, and Golf Road. Finalizing this list is difficult because
many FDOT projects were underway when this report was being finished.The City should share the study results
with FDOT. Recent FDOT projects likely improved drainage conditions on these roadways.
The projects are shown in Figure 23 and discussed for the rest of this section. Areas with an SWC prefix in Figure 23 are
areas with a previous stormwater complaint that were reviewed against modeling results. The City's 2024 ICPR model
did not suggest these SWC areas will significantly flood. They are noted in Figure 23 for future review and the
thoroughness of reporting and are discussed briefly in Section 9.2.2.14.Table 12 summarizes the final areas of concern.
Page 83 of 129
MUM
City of Boynton Beach 2025 Watershed Master Plan
, City of Boynton Beach ;` �:
City of Boynton Beach 2025 Watershed Master Plan
Table 12:Areas of Concern (as depicted in Figure 23)
Note:SWC areas were not validated by model results as likely to flood and are discussed in Section 9.2.2.14.
Approximate Relative Project Size/Likely
Area (Label) Location Summary of Suggested Action Time Horizon to Complete
Congress Avenue and
M-1 Surrounding Private Coordination with FDOT and LWDD. Sub-Regional
Properties Coordination/Immediate
Residential Area West of Large City Project/Multi-Year
M-2Bethesda Hospital East Significant stormwater engineering project.
p' (longer than 10 years to complete)
Coordination with Palm Beach County and LWDD. Sub-Regional Cooperative
M-3 Leisureville Area Strong candidate for sub-regional engineering Project/Multi-Year(longer than
study. 10 years to complete)
Neighborhood outreach project,coordination
South of E.Gateway Sub-Regional
M-4 Boulevard(Sea Meadow) with LWDD to create favorable conditions in Coordination/Immediate
adjacent canals.
Provide information to FDOT for some resolution,
M-5 Residential Areas Near coordination with LWDD,investigations into Sub-Regional Coordination/Short
Miner Road individual neighborhoods for potential drainage Term
projects.
Residential Areas
M-6 Adjacent to Lawrence Coordination with LWDD and Public Involvement.
Coordination with LWDD/Short
Road Term
MDS-7 Seacrest Boulevard Multi pronged approach. Largest City Project/Multi-Year
Corridor (longer than 10 years to complete)
MDS-8 S.Lake Drive Coordination with LWDD. Small Project/Immediate
MDS-9 Campinelli Boulevard Associated with M-3(should be packaged with Part of M-3 Project
this project).
Part of the MDS-7 project but
MDS-10 NE 16th Avenue Associated with MDS-7. should be prioritized during the first
phase of that project as a confirmed
flood complaint.
MDS-11 Ocean Parkway Associated with M-3(should be packaged with Part of M-3 Project
this project).
Small/Near-Term(Probability of
MDS-12 NE 9th Avenue Neighborhood Improvement Project flooding lower than other areas
featured in this study)
MDS-13 S.Ocean Avenue Tidal Flooding/Minor Stormwater Improvements
Small/Immediate(May have already
been mitigated)
SWC-14 N Evergreen Circle Previous concern,not confirmed with modeling No project needed at this time.
(likely addressed previously).
SWC-15 SW 11th Ave Previous concern,not confirmed with modeling No project needed at this time.
(likely addressed previously).
SWC-16 Palmland Drive Previous concern,not confirmed with modeling No project needed at this time.
(likely addressed previously).
SWC-17 Old Boynton Road Previous concern,not confirmed with modeling No project needed at this time.
(likely addressed previously).
SWC-18 S Federal Highway Previous concern,not confirmed with modeling
(likely addressed previously). No project needed at this time.
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City of Boynton Beach 2025 Watershed Master Plan
9.2.2.1 Area of Concern M-1: Congress Avenue
As Figure 24 shows,this portion of Congress Avenue and surrounding private property are likely to flood according to
study results. Spatially, this area is fairly isolated in terms of the City's access and infrastructure.The City can do very
little to address flooding in this area without cooperation from FDOT and LWDD. Since Congress Avenue is an FDOT
road, the City should share this section of this WMP with FDOT's engineers and begin a dialogue about this area. As of
the publication of this report, several FDOT roads within the City are being modified, so this concern may have been
previously addressed previously or will be addressed in the near future.The flooding in this area is directly connected to
the L-30 and E-3 z-E canals, which essentially border the area and control tailwater conditions. Both canals are under
LWDD jurisdiction.
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City of Boynton Beach 2025 Watershed Master Plan
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410LEGEND
F � �
�' ` DCity of Boynton Beach
Illt —Major Roadways
-
Identified Areas Prone to Flooding
Identified by:
Ie ! Model al
• Model+Stormwater Complaint /
• r • Stormwater Complaint
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es
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Figure 24. Area of Concern M-1
Page 87 of 129
1111111116
City of Boynton Beach 2025 Watershed Master Plan
9 2 2 2 Area of Concern M-2: Residential Area West of Bethesda Hospital East
As Figure 25 shows, model results suggest that considerable flooding may occur just west of Bethesda Hospital East.This
area has considerable relief compared to most of the City. The coastal ridge to the east, Interstate-95 to the west, and
pre-ERP stormwater engineering have essentially created a pocket of residential development that is relatively lower
than surrounding areas and with limited drainage infrastructure.This area comprises model basins B_E4_911 and
B E4 590 with a combined area of about 120 acres and an 18-inch CMP outfall to the E-4 Canal.The flooded area within
these basins is over 55 acres under 100-year/24-hour storm existing conditions and increases to over 80 acres for the
2100 Intermediate-High conditions. Even for the 10-year storm, the area impacted by flooding is predicted to be up to
27 acres. This flooded area is far too large to solve by providing additional storage capacity alone.
Flood mitigation for this area will require a detailed study and a likely suite of improvements that may include:
• Constructing swales and other retention areas along the roadways in the area to provide the maximum amount
of retention of runoff as practicable.
• Completing detailed geotechnical testing throughout this area (before finalizing any detailed design)to confirm
the presence of the St. Lucie-Paola-Urban soil type and the location of the seasonal high water table. The St.
Lucie-Paola-Urban land complex soils covering much of the area is suitable for exfiltration/French drain systems.
• To the extent practical, constructing stormwater storage areas in Forest Hills Park. A detailed search of property
records would need to be completed to determine potential areas where storage could be created.
• Improving the existing outfall capacity, including the possibility of adding a new outfall. Given the 2024 Florida
Stormwater Rule, water quality would need to be included in this project, such as creating swales (and of
considering soil amendments to improve the nutrient uptake may be advantageous).
Due to the changing nature of the State's Stormwater Rule,the City should conceptually permit the project before
undertaking any detailed engineering since land for treating and/or storing stormwater is very limited in this area.
Discussing permitting with SFWMD staff before determining a precise project configuration would be most cost
effective.
Page 88 of 129
MEM
City of Boynton Beach 2025 Watershed Master Plan
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..:. ,. 1 LEGEND
4
®City of Boynton Beach
�} AA —Major Roadways
1 ►!� i l `_- - Identified Areas Prone to Flooding
'' Identified by:
lir: "- Model
'+ , - - • P ;r± - a Model+Stormwater Complaint
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Figure 25.Area of Concern M-2
Page 89 of 129
City of Boynton Beach 2025 Watershed Master Plan
9 2 2 3 Area of Concern M-3: Leisureville
Leisureville is a known area of flooding, and model results were validated based on previous flood reports (see
Figure 26). It is densely developed and was constructed before modern stormwater regulations. This residential area is
relatively lower than its surroundings, and potential flooding is more complex because the adjacent canals and multiple
parties have jurisdiction over the area. In terms of stormwater infrastructure, Palm Beach County has jurisdiction over
part of Leisureville, and LWDD manages the canals that determine tailwater conditions throughout the development.
This is a very complex area to address in terms of flood mitigation because of these physical and sociopolitical
complications.
Even if the City modified the drainage infrastructure in its portion of Leisureville, significant assistance from LWDD
would be needed to create outfall conditions in which stormwater could be reasonably discharged to provide necessary
flood mitigation. Furthermore,the 2024 Stormwater Rule complicates the discharge of this stormwater because of very
limited space to treat the stormwater before discharge to the LWDD system.
However, with the cooperation of the various parties,this area could be packaged into a sub-regional adaptation study
that would be a strong candidate for grant funding. Due to the size and complexity of this area, future detailed study
with all parties previously mentioned should occur. The City cannot address the flooding in this area without significant
cooperation and via conventional engineering alone. Other considerations for this area of include:
• Dense development with little open space for stormwater infrastructure.
• Relatively high water table elevations and lower topographic elevations. This will limit the ability of engineers to
use conventional methods to treat stormwater within the Leisureville boundaries.
To make the project competitive for grant funding, the City should consider including the following elements in the grant
application:
• Project Partners: LWDD and Palm Beach County should be partners in the grant application process and should
be contacted as an early step in creating this project.
• Strong water quality and stormwater treatment components: This is a good area for this project element since it
would also likely improve the character of the area and residents would likely enjoy these aspects of the project.
Good candidate elements include trees with enhancements for stormwater treatment, bioswales, and
treatment planter boxes.
• Project components linked to reduction of heat island effects: This includes vegetation, walkable areas, and
cooling stations, among others.
• Educational and ecological elements, such as educational signage stations, walkable areas, habitat for various
species, etc.
• Public input:The community should be involved and provide input on the project throughout the entire process.
Page 90 of 129
IIIIIIIIF
City of Boynton Beach 2025 Watershed Master Plan
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LEGEND
i
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6y.„^c, FICity of Boynton Beach
—Major Roadways
.. •‘• Identified Areas Prone to Flooding
.. .
_
''..: Identified by
1 ,
: • Model
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Figure 26. Area of Concern M-3
Page 91 of 129
MEM
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.4 Area of Concern M-4:Residential Area South of E. Gateway Boulevard(Sea Meadow)
Similar to the previous area of concern, Sea Meadow is an area that model results suggest is likely to flood (see
Figure 27). This flooding was previously unknown to the City because it had not been modeled in detail before 2024 and
no reports of flooding appeared in City records. It is relatively lower than surrounding areas and is bordered to the south
by the L-22, an LWDD canal.This area is on the far west edge of the City on the south side of Gateway Boulevard.This
development consists of manufactured homes with varying finished floors. Most stormwater is managed via large
swales that line roadways throughout the subdivision.
As of the publication of this report, this project is flagged for further consideration by City engineers and is being
considered for water and sewer improvements by the City. However, the Sea Meadow subdivision is privately owned,
therefore drainage is not the City's responsibility and will remain so unless conditions change in the future. At a
minimum,the residents of this subdivision should be notified of the flood elevations determined by this study so that
their finished floor elevations can be modified as new homes are built and existing homes are modified.
Page 92 of 129
MIMS
City of Boynton Beach 2025 Watershed Master Plan
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....c., _ --_ -- ' — ...., - ,I —•—.10 City of Boynton Beach
- ` N. ' —Major Roadways
" j ' Identified Areas Prone to Flooding
Identified by:
. .. • Model
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ir _ • Stormwater Complaint
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iff High: 14.7
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D 1000 2 000 Feet
Figure 27. Area of Concern M-4
Page 93 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.5 Area of Concern M-5:Residential Areas Near Miner Road
Model results suggest that some areas near Miner Road on the east side of Boynton Beach are likely prone to flooding,
as Figure 28 shows. Miner Road is an FDOT road, so these model results should be shared with FDOT in the near future.
This will ensure that FDOT engineers can consider the study results study as roadway improvements are developed for
the area. Roadway improvements have been announced in the area over the past several years, making it possible that
potential flooding on Miner Road is being mitigated. This area also has no reports of flooding, and conditions in most of
this area in terms of drainage appear to be relatively well maintained. For example, swales are generally intact and
mowed, and drainage infrastructure is generally located throughout.
This area is a combination of newer, engineered, and permitted developments and older, pre-ERP developments.The
majority of flooding near this section of Miner Road is likely to occur in the older, pre-ERP developments. Some pre-ERP
neighborhoods of concern in this area include Dos Lagos, the townhomes near Meadows Boulevard (Meadows 300), and
Clover Bend.
The City could consider drainage improvements near and within these pre-ERP developments when feasible from a legal
perspective. Each development is very different in characteristics, meaning these engineering projects could be divided
into separate projects for detailed design. As part of this work, LWDD should be shown the study results to create
operational protocols that protect these neighborhoods when possible. Additionally, the residents of these
neighborhoods should be notified regarding the study results and be involved throughout any detailed design process.
Page 94 of 129
City of Boynton Beach 2025 Watershed Master Plan
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a I,il 'i LEGEND
",,A ,... ,-&- - , , t 4. q. 4= i • • .j 11 I.! / ci City of Boynton Beach
* "k."••.••• • •,x ' "- _,.....'4..." m :-._..- —Major Roadways
.____,-- ----- --- -- -43) - - • y/A
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feet NAVD88 t
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Figure 28.Area of Concern M-5
Page 95 of 129
City of Boynton Beach 2025 Watershed Master Plan
9,2.2.6 Area of Concern M-6:Residential Areas Adjacent to Lawrence Road
Model results suggest that private communities near Lawrence Road are likely vulnerable to flooding. Figure 29 shows
these areas.The City should share model results with LWDD to examine the likelihood of flooding in these areas.
Drainage systems in these neighborhoods are maintained and operated by separate homeowners associations with
some connections to LWDD canals.
This area exhibits potential pockets of structural flooding in neighborhoods that may not be meeting their intended LOS.
These neighborhoods include Lawrence Oaks, Citrus Glen, and Knollwood. Lawrence Oaks was likely constructed before
ERP development requirements. Citrus Glen is gated and was likely constructed around 1988. Knollwood is gated and is
privately operated and maintained. ERP records suggest that Knollwood was constructed around 2006.
Flooding in these areas appears to overall meet ERP requirements, with most of the anticipated flooding on the
roadways. However, flooding will become increasingly likely in future years. The most cost-effective action the City can
take in this area is to work with LWDD to produce favorable outfall conditions for these neighborhoods.The City should
also work with these neighborhoods on an ongoing and prioritized basis regarding maintenance of their drainage
systems to encourage practices to keep debris out of inlets and stormwater pipes.
Page 96 of 129
IIIIIIIIIIk
City of Boynton Beach 2025 Watershed Master Plan
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-,-,,544-4 -4-3r'...-..".-111"
.:1_,......4.14.GA..61.. 44. .....,i' --'Atka_ 0 7,. --•4; . '4 .1,' ",-- ',--
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„, -,, '. ,, .. .--7. ,A ivi . • : • '' '.41:3.04.1. •Er - I I li-
.- -:-. '4._ •-• 1- . ir--:., ,_ .,„ ., ,. 4
....;
' - 1. . : LEGEND 1
., 0,•-. '-:-- 111 ,. __
_.„ illip. ,) c •-• . -"..miu4 • - c City of Boynton Beach
, ' L....
2 , , 1 iii, : — + C Y 4,4,0_14 r —Major Roadways
4 'u ' •4*A•Itii.P4 v —4-•,...ry,'
-', -' ' 1,4 e ' - ” ' . , '' , I ' Identified Areas Prone to Flooding I.
H •"e't Ilit r. : : ,--, _ , .44 • .. Identified by: th,
.1 '-.. ' ..:.\1: 4, -• : '...' ''"'. li.fr a, i' • Model
- ' ' • •:.•'-.4
. '`• (--.4 r ,;#t..' A , , •, ._. Model+Stormwater Complaint
. .: "-
. ....,,„ . .., , i.., -:.,-- -,. •. - . Stormwater Complaint
... .!,;21c: , .........114 ,
ra:4:11,.. 100YR,72HR Storm Event
. , - --I.., - 4...
t
- . 1
Adip4-, • .-- ,1'1, -' -41 ... 4.4.1 -
O 007 015 0 3 N
II\
Figure 29. Area of Concern M-6
Page 97 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.7 Area of Concern MDS-7.•Seacrest Boulevard Corridor
MDS-7 is indicative of flooding that occurs throughout the entire Seacrest Boulevard corridor. MDS-7 is the most north
section of flooding along the Seacrest Boulevard corridor identified by this study (Figure 30). The CCVA also noted that
this area floods significantly. Additionally, the Seacrest Boulevard Corridor south of the Boynton Beach/C-16 Canal was
studied in detail by CDM Smith in 2023-2024. This study generally agrees with the CDM Smith study findings for the area
south of the C-16 Canal.
The Seacrest Boulevard Corridor is a large residential area of pre-ERP development that is exceptionally challenging to
address in terms of stormwater management for many reasons. Similar to some of the areas previously discussed,
development is dense and little available is space for conventional storage and treatment of stormwater. The sheer
volumes of stormwater generated in this area compared to the 2024 Florida Stormwater Rule requirements also make
this area particularly challenging to address. In addition, a significant ridge east of Seacrest Boulevard makes much of
this corridor more prone to flooding. This area is essentially a sub-regional depression between the coastal
ridge/Interstate-95 and a milder ridge due east of the roadway. Some existing stormwater infrastructure is in this
corridor but is limited and similar to many other areas throughout Florida.This infrastructure continues to decline in its
ability to provide adequate relief of flooding and ultimately deliver the desired LOS.
Since this is a City-wide study and most of this area has been studied in detail, areas that CDM Smith previously modeled
in detail were not re-evaluated. Instead, this study shows that similar hydrologic conditions exist along the entire
Seacrest Boulevard corridor(including areas north of the C-16). This study re-used significant model geometries from
the CDM Smith model south of the C-16 canal. An evaluation at that scale would be expected to yield similar results for
this study. Collective also reviewed all reports for this area in detail in preparing this WMP. As such, this study agrees
with the CDM Smith study that conventional engineering techniques will likely provide some relief for smaller and
moderate storm events in the entire corridor. However, this corridor will continue to be vulnerable to flooding and
increasingly so in future years, as Appendix H shows.This is also an area of exceptional sociopolitical vulnerability.
Therefore,this area is being added into the largest project for this study that would include a two-phased approach to
the improvement of conditions along the entire Seacrest Boulevard corridor. Figures 30A and 30B summarize a potential
multi-pronged approach for the entire Seacrest Corridor.
The findings of this study suggest that:
• The City may want to consider using strategic stormwater vaults in this area if available properties can be
located. Other types of utilities are likely dense in this area, so the retrofit and use of these vaults may not be
possible. However, these vaults may assist some areas near Seacrest Boulevard with some flood relief.
• Engineered projects similar to those suggested in the CDM Smith study will likely alleviate flooding for smaller
and moderate storm events along the entire Seacrest Boulevard corridor for the near term.The LOS
requirements in the CDM Smith study were relatively modest compared to some described in some sections of
this report, and this study evaluated larger and future storm events.
• Detailed geotechnical testing will be needed to truly evaluate each project location. However, the measures
suggested in the CDM Smith report will likely provide significant relief to some areas. These projects could be
designed relatively quickly and will likely provide "early wins" and some much-needed rapid relief of flooding in
the area (these are shown as the pink triangles in Figures 30A and 30B). This study can provide a baseline for an
equitable approach to the corridor(in terms of engineered projects) because the entire corridor was studied
rage 98 of 129
City of Boynton Beach 2025 Watershed Master Plan
using the same methodology.This is the first part of the recommended projects for this area,which can also be
considered a conventional civil engineering approach.
• Flooding in this corridor is so extensive and significant that larger,visionary projects will be needed to truly
address it.These projects would take many years and would need extensive permit coordination with SFWMD
because they would likely require the storage and discharge of large volumes of water at times. Positive outfalls
would also be needed to ultimately send the stormwater to the Intracoastal Waterway.This is also an area
where pumps might be considered in the future.
• This area is very likely to be awarded grant funding. Flood relief for an initiative this large should be carefully
evaluated with a cost-benefit analysis that includes the age of the structures and infrastructure of the area.This
would likely be a long-term and significant investment for the City,so the details need to be considered both for
current and future conditions. Cities such as Daytona Beach have been successful in similar initiatives, but they
took many years. Projects of this magnitude can sometimes take 20 years or more to complete, but many local
governments have found them to be worthwhile.
Page 99 of 129
City of Boynton Beach 2025 Watershed Master Plan
. 4f-- 4 : irr.„6„ , rr
d `4r a r.t ; l�T�
F.
y •
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lk Vt.
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tt:ilt 4(_41;.
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. ,..z
. . i,,, . I LEGEND
,,:„...,..
. :.,
City of Boynton Beach
r • •� `gyp —Major Roadways
`�. • Identified Areas Prone to Flooding
4 Identified by:
+ a.Model
c' i 4.Model+Stormwater Complaint
= �:Stormwater Complaint
.t.4.44t1
n \.: .t / • 100 Year,72 Hour Storm Event
�^ • ���, feet,NAVD88
r.
:1,.
High:14.7
iAI t ,
� f a � lal Low:0
'
0 0.025 0.05 0.1 N
.19
G 250 500 Feel
Figure 30.Area of Concern MDS-7
Page 100 of 129
City of Boynton Beach 2025 Watershed Master Plan
. .r LEGEND
...4 ,4- j'E :City of Boynton Beach
=`
`" '' •4-: —Major Roadways i
7
- .• Phase 1 Project Locations
''T ' Boynton DEM
"' Elevation(feat.NAVOBBI
n 11 High : 57.0933
-
c Low : -2.75367
,a, j
�I�':w . X -ir
x mi.._ , -s T,- 1`"..if
44 I i Graz e 1 NV ate' •a
A
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; +
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OrLC=f6-
•
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4,,. A
Figure 30A. North Section of Seacrest Boulevard Corridor
Page 101 of 129
1111.1.1111
City of Boynton Beach 2025 Watershed Master Plan
1,
® - ,. IJCity of Boynton Beach
._. ,•- r_- ..� —Major Roadways
Do it - „ „ . _ Phase 1 Project Locations
a Boynton DEM
V b< '�'' Elevation(feet,NAVD88)
Highh 57.0933
Hw . ",t'
�W Bcynto.? 3cach Epud Statey804. (n
Low : -2.75367
?' .• , ., • • ,.�
-,-,)2...--i
RI
T
' - - , \i ... ' of - .4t,„.. . r
\V 1 — ''' -.. ,
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P W Wool•r .ht ;Aa E Woolbnyht Rd I -
'I. l •. •I':
.
10114 IMUNMI
iii f .• y
l
��, tJ. - - ��,,,���'''' -
...., .1.._ . , .,.i .
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7 .,.
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3 r • •cT. C _.. Ocean
14 . ' _,4
a
#
tr _
Aset"---:4 la,,,V,• lab e.--, -, "-:*
>..
Figure 30B. South Section of Seacrest Boulevard Corridor
Page 102 of 125
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.8 Area of Concern MDS-8:South Lake Drive
Area of concern MDS-8 is in the south section of the City, where a residential area is bordered by two portions of the L-
30 Canal. Most of the development is relatively older, and modeling conducted for this study aligned with the flood
reports received from this area. Most of the parcels in this area are directly connected to the L-30 Canal, so the City
should discuss these results with LWDD. Furthermore, as homes are modified and/or reconstructed and/or the area is
redeveloped, higher finished flood elevations should be used based on the results of this study, as opposed to the flood
elevations provided by the official FEMA floodplains for this area. Figure 31 shows this area.
Page 103 of 129
City of Boynton Beach 2025 Watershed Master Plan
,: -•rte;
.t -.v-.+FSC ,' TTfr 44 .41/11,4ifir.i,.: �g-
y
` _t•', •rya
.fie*
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MDS-8
-4‘r*, ss i 0 \ACZ A
/ •
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a
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. 0 ,
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er,. 1
s A.�
ttitLEGEND
0City of Boynton Beach
- —Major Roadways
ww
Identified Areas Prone to Flooding
r
t Identified by:
* • Model
Model+Stormwater Complaint mi.
4 Stormwater Complaint
100 Year,72 Hour Storm Event
feet,NAVD88
up High:14.7
1, Low:0
1.
0 0 025 -�- 0.05 0.1 - N ^
Ie..
0 250 500 Feet
A
Figure 31.Area of Concern MDS-8
Page 104 of 129
1111111011
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.9 Area of Concern MDS-9: Campinelli Boulevard
MDS-9 is a confirmed flood complaint, but this area was previously identified and is connected to the M-3 project in
Section 9.2.2.3.The model results showed some of the most significant depths of inundation in this area, which is shown
in Figure 32.
Page 105 of 129
City of Boynton Beach 2025 Watershed Master Plan
A .....„,----'\* -..4,41\*? - .4
W Woolbright Rd 4, , li•; -. '
r
, ,e „,, ,_,....,.. ,It..:AUtouNiedill fil` '' t: : i
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•
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41.
/Lq \��. —1l
,4
•
AJ.
N.
4 ,. \ �� MDS-9
x!,;,,,
LEGEND
SW 23rd Ave u, C City of Boynton Beach
,- ..fit.' % .11. 47.11111:
• -Major Roadways
14 • - IF" ._.4.--11114—_,,,,.-�. i',_.Y Identified Areas Prone to Flooding
, i I '�-+- 31- '1 „'AR r., 4,^ , - .)00. Identified by:
- r,.l•-` moi.„ .S Model
-:,. , �,� i v Model+Stormwater Complaint
I� •P,1,;, i r 1 '• , ' ♦Stormwater Complaint
100 Year,72 Hour Storm Event
�.y _ „i{ �. vd - feet,NAV .88
• 4” e 1-11 . e ? . I �-1.,%'T : i _ :4- a •
High:14.7
+fir'{
�` p -mac , , ,,-,,,,,..4#00 i,i,* .:.if Low:0
O 005 0.1 0.2 N
nk.
a 500 1,000 Feet
Figure 32.Area of Concern MDS-9
Page 106 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.10 Area of Concern MDS-10: NE 16th Avenue
This area of concern is included in the previous MDS-7 discussion but is also a confirmed flood complaint area.The area
is noted here separately so that it is prioritized for detailed design as part of the larger first round of"early-win" projects
discussed in Section 9.2.2.7. Figure 33 provides a detailed map of the area.
Page 107 of 129
IIIIIIIIIr
City of Boynton Beach 2025 Watershed Master Plan
—=719
• t. Q 'a.......„,,,,,--:—.......it, ',A ,. i,40 OCity of Boynton Beach
, : . 4/, -4,,LA' , .',.---w ' .. 4 1 -4:it #.. Identified by
• Model
Ai
4 isiolispa. .
,,-. ' .., , ' --. •••",‘"„,.--, - 0' — --- -1-'.-7-,..7.,...i, j:;4 r _
$ , r`-'1,. 1,-; . ..,. _
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arommul
. ,,,. .. .1„,, 1,7ttate, ..,...--- . ‘ ,, ,i' F., ' -..?„,. , -.-•-•-9 t „Ni,,i...,.
-.;-.,:.. ,. -,..: -0 I. ,t, - -, , .,.. - 7,. ..„ , ,. — • ap
— •-• —.10_,. 4. , . . ... .
.-1:? ii,..,.., _.... , . ._ ..
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es
" s00 .v=°~
A
Figure 33. Area of Concern MDS-10
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.11 Area of Concern MDS-11: Ocean Parkway
MDS-11 is a confirmed flood complaint area but was previously identified and discussed as part of the M-3 project in
Section 9.2.2.3 of this report. This area is east of the E-4 Canal, and model results showed some of the most significant
depths of inundation in this area. Figure 34 shows a detailed map of the area.
Page 109 of 129
IIIIIIIIIIr
City of Boynton Beach 2025 Watershed Master Plan
sAv11111001p1
f` 0,4t LEGEND
S
N`Ny (=City of Boynton Beach
e.—Major Roadways
} ' Identified Areas Prone to Flooding
�. = o h Blvd n
.' 't, * p ,f Identified by:
��, . : rty + _• Model i
.• Model+Stormwater Complaint
• Stormwater Complaint
m 100 Year,72 Hour Storm Event '
,p feet,NAVD88 •
pil High: 14.7
Z.
MDS-11 • ' Low 0
A 'Pt-.
ortk.4.: „. l__-,_ ce., 3,•.,.
4 k. 11r?!1. yyam,
V'• ) -
.) Ocean Dr
_17
• _
G
�1-444 ',
w PKC
itibil. i `61. i.,4‘,
til; 1
1 S
1,
I , M
C
0
14.40.
G
ski, i 4 N.
. 4,. N .,.
, ,.....,;:ir*,4;,‘,„„4,--\,, ,,4+.. • 4* 's .. a-qv'," $ . \4 e'-;!.4441:4
,fir
0 005 0.1 02
0 500 1.000 Free
Figure 34. Area of Concern MDS-11
Page 110 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.12 Area of Concern MDS-12:NE 9`h Avenue
MSD-12 is an area with active flood complaints and some chance of structural flooding as shown in Figure 35. However,
modeling suggests that flooding is primarily likely to occur on roadways, and the severity is relatively lower than the
other areas featured in this study. Given these factors, a traditional neighborhood improvement project would likely be
successful in this area.This project could primarily consist of traditional civil engineering measures, such as inlets and
storm sewer, to alleviate the pockets of flooding near homes.
Page 111 of 129
11111.1111
City of Boynton Beach 2025 Watershed Master Plan
f • '54 i -- r 't ,. it ,..- p-'u'.d-,h ,-dila
.,.. , r 1�r. I. •.. LEGEND
– 7 EJCity of Boynton Beach
—Major Roadways li
Identified Areas Prone to Flooding r'
' Identified by.
.1 gip o v gipp .i./+ • SO , Model
os A . C-1 V_ ` _ Model+Stormwater Complaint
9 Stormwater Complaint
V.-.,, ..
• 100 Year,72 Hour Storm Event
-;*4' •
+ . feet,NAVD88
•} rt '.{ ``y„4.'ci i„ AF ,, j "qc. row, High 14 7
x e 1 • aF�R Low U
44
out
.rte ,"II •fj Y - .../ ♦'. r { r fT7
t.
•
4 laiit le'7.7-..1 1;99111111.
-... � Fit'' _ Fs r. T S
"MDS-1.r..42 ,..1.-= .44 4riiii a f;i
NE�Ave •• '
I 't" tµ! t.t
V a .:; 141 ; il,'."‘ -,,rikti.
....... . s
......,
..... ,
. 4 • , . , c.,_.
i....... ,t,
; 1110 ..! ,.t' ; i -.4 .1,...,44. s.
t ve; t f
i-iii
o 0.025 5C5 ,I N
Yes
0 250 500 Feet
Figure 35.Area of Concern MDS-12
Page 112 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.13 Area of Concern MDS-13: S. Ocean Avenue
MDS-13 is a known area of flooding, so it is noted here for documentation purposes. The City has diligently worked to
reduce both tidal and rainfall-induced flooding at this location, and much of the inundation in this area has likely been
reduced as of the publication of this report. Figure 36 shows this area.
Page 113 of 129
City of Boynton Beach 2025 Watershed Master Plan
. , --
y- r LEGEND
Yui #. `
I !�City of Boynton Beach
. ) 1 ; -_ 'v —Major Roadways
Identified Areas Prone to Flooding
-,� sa. I. Identified by:
F `' n ' • Model
j ° , t. _ . .., • Model+Stormwater Complaint
s.
r teI T ' ` • Stormwater Complaint
',,F., •- SO I -, .., ` l 100 Year,72 Hour Storm Event
!�I feet,NAVD88
t`s High:14.7
4 • � L t..> , il' yR' v.. I- y
y�,' Low:0
ark . Fi 9J .i LS
ill
/Am_ 1 .-% . ; t. ..... I` , 4 A 'C-k. ___ 1 ,0, ,
State Hwy 804 It's' '" -
� .=i \� ,. ru.>. . X71 life 1
e.,
ki.'.tit!
'71.i.„', 7 k':.:44.4:: ;11 - : i _ •_-
1.11 4.4 t . I
•
Tir. -7411
y'I `.. „,„ k.f
f��' Ip.7l
`' s;Y.•,,.,w,,,, i,. b r+l► 4 ''MDS-13 . ii' :
fit ,,1.,__ t
vs t .. y it'
= E Ocean Ave _
!IJ a In t „ tey /
oli—, � `
...,,, i v. . ,
J i
i ,1 ' "Mani :yililltb. , . ,,,.--; ,
,_
_ ••� �„� "ate
, ...„
ti.,
, . .
iiiii ,,,
. , ,, ,
IV 1 , ' .'I"-• .7-zoii-, IV - . iiiille.--- -'1""-"'. ' 7. .4k - '-I I .' z
' 1St Ay:* . !I ••
•
tr yy
1.- ' me-,....!- t if I ,-.11---4 , its
] i.t. K r r . .I rF
K. k A Air--'c.-1. • - t __ ..A..-- d.M.�� .,....•\!.\\.4 r.j•:.\,,„,...zu.,Q.,_.,.„, .
0 0.025 0 u5 0.1 N
0 250 500 Feet A
Figure 36.Area of Concern MDS-13
Page 114 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.2.14 Stormwater Concerns Not Validated by Model Results(SWC Areas 13, 14, 15, 16, 17, and 18)
All of the City's previous stormwater concerns were reviewed against model results. Of these, six did not exhibit flooding
beyond permitted limits.This type of flood concern is common in Florida. All of these areas were reviewed in detail, but
generally this type of reporting can occur due to one or more of the following reasons:
• In Florida, many of our roadways are permitted to flood at times. In fact, roadways are generally part of our
stormwater management system in Florida, particularly for large and/or intense storms. Local governments and
various agencies sometimes receive reports from members of the public of flooding that was previously
designed for and permitted. Although the flooding can temporarily impact communities, it is permitted by water
management districts and usually subsides fairly quickly.
• Often, maintenance issues can exacerbate flooding. For example, landscape materials like palm fronds, lawn
clippings, coconuts, garbage, and various debris can temporarily clog inlets in South Florida. If this occurs, it can
cause some flooding that can vary in severity depending on conditions.The City and other agencies provide
education on this issue due to its prevalence throughout Florida. The City and other agencies, such as FDOT,
provide ongoing maintenance to prevent this issue.
• The malfunction of a structure could cause flooding in some of these areas. Boynton Beach has many operable
and complex structures that control flood elevations throughout. The City does not have control of the majority
of these structures. Many of these are permitted by other agencies and maintained by those agencies or private
parties.
• Occasionally, another type of flooding, such as a water main break, is reported as a stormwater issue.
Page 115 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.2.3 Recommended Prioritization of Structural Projects
Table 13 provides a prioritization of structural projects.This is intended to group projects by timeframe so that
vulnerable populations throughout the City are prioritized, along with lasting floodplain management practices. It is also
intended to produce some early successes for the City so that regulatory hurdles can be resolved on simpler projects.
Lessons learned can be leveraged on later and more significant projects.
Page 116 of 129
.111111111
City of Boynton Beach 2025 Watershed Master Plan
Table 13: Prioritized Structural Projects and Initiatives
Suggested Project Final Project Likelihood of
Project ID Name Suggested Partners Grant Award Overall Timeframe and Notes
Initiation
Seacrest Boulevard Community leaders, Begin Phase 1 Immediately(this is
MDS-7 Corridor FDOT, and Palm Beach Very High a lengthy and two-pronged
Adaptation
County project)
Initiative
Leisureville Community leaders, High (with Begin Coordination and Grant
M-3 Adaptation Palm Beach County, LID/Water Preparation Immediately(this is a
Year 0-3 Initiative and LWDD Quality/Nature lengthy project)
Based Solutions)
Lawrence Road
Neighborhood
Outreach and Community leaders Immediate (due to potential issues
M-6 Low
Stormwater and LWDD with existing LOS)
Engineering
Support
South Gateway
Boulevard
M-4 Stormwater Community leaders Low Immediate
Monitoring
and LWDD
Program
Year 2-4
South Lake Drive
Neighborhood Community leaders,
MDS-8 Outreach and LWDD Low Immediate
Engineering
Support
South Congress Community leaders
M-1 Avenue Resilience Low Near Term
Initiative
FDOT, and LWDD
M 2 Southeast Boynton Community leaders Moderate Near Term
Resilience Initiative
Southeast Miner •
Year 5-10 Road
Neighborhood Community leaders,
M-5 Outreach and Low Near Term
LWDD, and FDOT
Stormwater
Engineering
Support
NE 9th Avenue
MDS-12 Neighborhood Community Leaders Low Near Term
Improvements
Page 117 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.3 Non-Structural Controls for Water Quality and Quantity
9.3.1 Stormwater Manual
Given the results of this study, the City should update the existing Stormwater Manual that was released in 2009. This
updated Manual should be referenced in the City's Land Development Code. The City should ensure that the updated
manual includes the following topics:
▪ Required/acceptable hydrologic and hydraulic analysis techniques
• Minimum pipe diameters and materials
• Minimum pipe slopes
• Minimum pipe cover requirements
• Acceptable distances between access points (manholes or similar) to facilitate cleaning and maintenance
• Required design storms frequency as well as associated rainfall depth, distribution, and duration
• Peak discharge requirements
• Storage and treatment requirements
• Acceptable low impact development features
• Enhanced Level of Service requirements (e.g., 10-year storm for local roads, 100-year storm for structures and
evacuation routes)
• Data delivery standards
• Additional requirements for development and redevelopment in watersheds deemed impaired according to water
quality data/FDEP
Technical guidance may be provided as well for design approach and hydrologic and hydraulic parameters.
Page 118 of 129
MEM
City of Boynton Beach 2025 Watershed Master Plan
9.3.2 Maintain and Strengthen Collaboration and Partnerships
Similar to most watershed studies, the results of this evaluation further demonstrate the City's interconnectedness to
adjacent jurisdictions and agencies. Given these interconnections, the following mitigation measures are recommended:
• Continued participation in regional efforts related to stormwater management, including but not limited to the
Southeast Regional Florida Climate Change Compact, Coastal Resilience Partnership of Southeast Palm Beach
County, and MS4/NPDES Consortium. City leadership should continue to dedicate resources and staff to these
efforts since many of the issues handled by these partnerships are more cost-effectively managed on a regional
versus City level.
• Sharing the results of this study with LWDD, specifically results that interact with its system of canals and
structures, is critical. The City will continue to be directly impacted by operational and management decisions
from LWDD. Creating a two-way flow of information is critical to the future of both entities.The City may also
want to consider directly sharing key datasets, models, and methodology used in this study with LWDD. Finally,
the City may consider either updating any current agreements or creating a new operating agreement with
LWDD with respect to structure flows into the City's system.
• Sharing the results of this study with SFWMD is critical, specifically the areas that interact with its system of
canals and structures.The City should continue to attend the SFWMD Quarterly Resilience Forums and review
their published documents as plans to alter their infrastructure near and within the City are developed.The City
will also want to ensure that flooding data are timely and accurately reported to SFWMD using the SFWMD
Flooding App: https://survev123.arcgis.com/share/e41f189ec72d48ecb70d59d56120ca81
o Similar operating agreements previously referenced might be beneficial by a tri-party structure that
includes the SFWMD.
• Palm Beach County is integral to the City's stormwater management strategies.The City should continue to
attend the County's meetings for the Local Mitigation Strategy and Community Rating System. The City should
also share the results of this study with the County, particularly since the County is also preparing a Watershed
Master Plan.
• Coordination with FDOT will need to continue given the prevalence of major FDOT roads and drainage
infrastructure throughout the City.The FDOT drainage ditches due west of Interstate-95 and south of Ocean
Avenue have flooded in past years. Other large FDOT roadways are routinely and significantly inundated
throughout the City, including but not limited to Federal Highway, Boynton Beach Boulevard, Hypoluxo Road,
and Gateway Boulevard. Currently, several FDOT roadway improvements are underway in the City, and the
City's ICPR model should be updated to reflect changes in major FDOT roadways as they take place.
• The City should maintain involvement in regional activities to ensure railway modifications do not cause
increased inland flooding. Both this WMP and the CDM Smith Study suggest substantial inundation immediately
west of the Brightline track near Federal Highway is causing an unfavorable outfall condition for the residential
areas west of that rail line (CDM Smith, 2024).
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City of Boynton Beach 2025 Watershed Master Plan
As a courtesy, unincorporated areas outside the City limits that may experience significant flooding are tagged in
Figure 37.
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Page 120 of 129
City of Boynton Beach 2025 Watershed Master Plan
9.4 Protection of Sensitive Natural Areas
9.4.i Protection of Lake Ida and the Greater Central Palm Beach County Chain-Of-Lake(
Given the recent Total Maximum Daily Load (TMDL) development for Pine Lake in West Palm Beach and the extended
regulatory activities due to the impairment of Lake Ida, the City should consider establishing and supporting a dedicated
Chain of Lakes Data Water Quality Consortium. The City directly depends on both the water quality and flows from Lake
Osborne, which is connected to the greater Chain of Lakes starting in West Palm Beach. These lakes likely have specific
technical considerations from a water quality perspective because they are part of the larger canal system, and although
they are technically not classic lakes, they behave hydrologically like meandering canals.
Throughout the history of the Clean Water Act,jurisdictions have saved significant resources by collaborating beyond
jurisdictional boundaries to collect data, evaluate systems, and mobilize for regulatory action. The City would benefit
from starting the TMDL development process since the City cannot readily mobilize resources or data and the science
used to place regulatory conditions on the City may not be optimal. Figure 38 illustrates the interaction between the
Palm Beach County Chain of Lakes.
Page 121 of 129
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City of Boynton Beach 2025 Watershed Master Plan
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Page 122 of 129
MOM
City of Boynton Beach 2025 Watershed Master Plan
q.4.2 Protection of Existing Preserves and Wetlands
Because the City is nearly built out, Collective highly recommends that the City encourage the preservation of existing
natural areas and wetlands. The City should consider code revisions that encourage the creation of greenspace, pocket
wetlands, and tree canopy projects. These projects will assist not only with stormwater issues but will also reduce urban
heat island impacts.
9.5 Public Engagement
The City should continue public engagement activities and co-host and facilitate recurring events with community
leaders at local settings. Continuing to build a coalition of community leaders who understand stormwater and climate
issues on an ongoing basis will be the most effective mode of public engagement for most South Florida cities in future
conditions. Residents that are located in areas flagged by this study (see Figure 23) should be involved in this ongoing
coalition of community leaders.
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City of Boynton Beach 2025 Watershed Master Plan
9.6 Revised Level of Service
As mentioned in Section 9.1, a new Level of Service (LOS) should be considered by the City to mitigate flooding. One
potential set of LOS criteria are provided in Table 14. These criteria are similar to other local governments throughout
Florida that have modernized in recent years to better address flood mitigation in future years.
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City of Boynton Beach 2025 Watershed Master Plan
Table 14: Recommended Level of Service Criteria
New Buildings:The finished floor elevation of all new building structures shall be set above the 100-year flood
elevation. [1]
II. New Roadways Access:New roadways shall be designed to be passable during flooding under the following storm
events[1].
Road Type Design Storm,72-Hour Duration
A. Evacuation 100
B. Arterials 100*
C. Collectors 25*
D. Neighborhood 25*
* For collectors and neighborhood roads, roadway flooding less than 6-inches of depth measured at the outside edge of
pavement is considered passable.Arterial roads must have less than 3-inches of flooding at the outside edge of
pavement. No flooding is permitted on any portion of an evacuation road.
III. Existing Roadways Access:The level of service for improvements to existing roadways may be adjusted from the above
criteria, based on existing conditions such as existing road right-of-way area,on-site and adjacent topography,and
vehicular use of the roadway. [1]
IV. New Site Development:For a new site development,the stormwater runoff analysis shall be based on a 25-year,72-
hour duration storm event[1] and shall not cause any adverse flooding impacts on-site or off-site. Deliberate flooding of
a parking area in a 25-year 72-hr storm event[1] is not allowed.
The City Stormwater Engineer can allow a greater level of flooding during the peak of a 25-year storm event on a case-
by-case basis, if sufficient documentation is provided to show that this level of flooding cannot be avoided and the
flooding can be demonstrated to not adversely impact public health and safety, natural resources or other property.
This criteria can only be met by providing a signed and sealed report from a qualified professional engineer.The flood
depth and duration(pre-and post-development conditions)of the flooding must be established in the report,and
justification provided to show why public health and safety is not compromised.
V. Areas Subjected to Tidal Tailwater Conditions: All systems must, in addition to the provisions of water quality, be
designed to be functional for all tailwater conditions that may be encountered by events equal in frequency to
the design storm event.This may entail consideration of storm durations different than the standard 24-hour storm
event.Variable tailwater stages should be considered if they have a significant influence on the design. A Minimum
Tailwater Elevation is required of 3.0 ft. NAVD88 for Non-Critical Infrastructure and 4.0 ft. NAVD88 for Critical
Infrastructure -Applicants may propose to utilize alternative tailwater elevations due to site-specific constraints but
should take into account current and future conditions at the receiving water.
All systems must provide a gravity discharge that effectively operates under normally expected tailwater conditions.
Consideration should be given to systems discharging to tidal water bodies to be functional during the Mean
Higher High Water(MHHW) level of normal diurnal tides,spring tides,and water levels elevated by normal sustained
wind patterns.Systems discharging to non-tidal areas will be designed to be functional throughout the wet season.
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City of Boynton Beach 2025 Watershed Master Plan
Determination of the wet season high water table shall be based on geotechnical and/or biological indicators as well as
observable stain lines should be used to support and document the tailwater used for design.
[1]All projects must provide a signed and sealed flood study utilizing a FEMA-accepted hydrologic and hydraulic model to determine
peak flood elevations for relevant design storms. Modeling must reflect recent boundary condition data and either recent survey
data and proposed grading or LIDAR data and proposed grading. No existing Environmental Resource Permits or Lake Worth
Drainage District control elevations may be used to establish boundary conditions.Where boundary condition information is
unavailable,the relevant Boynton Beach WMP established peak elevations and/or tidal elevations may be utilized for the design
storms in question. If an Environmental Resource Permit is submitted to the South Florida Water Management District,a copy of the
entire permit application must also be submitted to the City and major engineering assumptions must match between both
applications.Single-family residences are exempted from the requirements in this table.
9.7 Low Impact Development and Green Infrastructure
The City should consider making amendments to relevant Land Development Regulations to provide incentives for
redevelopment projects.This will benefit the City in terms of compliance with newer stormwater regulations. If this
modification is made,the City's engineering review procedures should also be modified so that these measures are
reviewed against modernized standards that involve water quality,specifically nutrient removal efficiencies, and if
possible,continuous simulation of the proposed measures(when relevant).
9.8 Stormwater Retrofits— Make them Routine
The City should consider integrating a stormwater review into all projects where the City engineers, or consulting
engineers, evaluate whether other infrastructure projects can cost-effectively include stormwater improvements. For
example, if a water or sewer line is being disturbed, making concurrent stormwater improvements is often cost effective.
This technique of "stormwater on every project" is generally less disruptive to the public because areas are disturbed
fewer times,and the incremental gains will add up over time in reducing flooding.
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City of Boynton Beach 2025 Watershed Master Plan
10.Citations
CDM Smith. "City of Boynton Beach: Downtown Stormwater Modeling Evaluation." Task Order No. UT-2C-03, November
2023.
City of Boynton Beach: San Castle, Lake Boynton Estates, and Chapel Hill Stormwater Evaluation Final Report. CDM
Smith, December 2021.
Coastal Resilience Partnership, Southeast Palm Beach County. "Multi-Jurisdictional Climate Change Vulnerability
Assessment." Climate Change Vulnerability Assessment Update(2022), CRP CCVA Appendix 9.
https://discover.pbcgov.org/resilience/Documents/CRP%2OCCVA%20APPEN DIX%209.pdf
Coastal Resilience Partnership, Southeast Palm Beach County. "Multi-Jurisdictional Climate Change Vulnerability
Assessment." Final Project Report,July 2021 Version 1.1.
https://discover.obcgov.org/resilience/PDF/20210903 ADA CCVA FinalReport.pdf
Federal Emergency Management Association (FEMA), "Preliminary Map Services" Digital Flood Insurance Rate Map
(DFIRM). Palm Beach County, FL(Jan. 2024).
https://hazards.fema.gov/femaportal/prelimdownload/searchResult.action
National Oceanic and Atmospheric Administration (NOAA). "Global and Regional Sea Level Rise Scenarios for the United
States." NOAA Technical Report NOS CO-OPS 083,January 2017,
https://tidesandcurrents.noaa.gov/publications/techrpt83 Global and Regional SLR Scenarios for the US fi
nal.pdf
National Oceanic and Atmospheric Administration (NOAA). "Tides and Currents, Relative Sea Level Trend." Lake Worth
Pier, FL Station Home(1920-2020).
https://tidesandcurrents.noaa.gov/sltrends/sltrends station.shtml?stnid=8722670
South Florida Water Management District(SFWMD). "Arc Hydro Enhanced Database (AHED)" SFWMD Arc Hydro
Database (FGDB Download),South Florida Water Management District Open Data. South Florida Water
Management District Open Data
US Census Bureau. "Boynton Beach City, Florida." Quick Facts, Population Estimates(V2022).
https://www.census.gov/auickfacts/fact/table/bovntonbeachcitvflorida/PST045222#PST045222
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