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​What is the Future Conditions 100-Year Flood Map?

Adopted by the Broward Board of County Commissioners on June 15, 2021, as part of the Code of Ordinances, the map (Plate WM 13.1 - Future Conditions), helps to ensure community resilience by ensuring that future flood elevations are incorporated in the planning and design requirements for lowest habitable finished floor elevations for residential and commercial structures - an action that will help protect against future flood risk and potential losses and preserve the affordability of flood insurance in Broward County.​

Future Conditions Map Series​

​​​​​​​​​​​​In May 2017 and June 2021, the Broward County Board of County Commissioners adopted Water Management Plate WM 2.1- Future Conditions and Water Management Plate WM 13.1- Future Conditions, respectively. 

New applications for a surface water management license, applications for major redevelopment of existing sites, and applications for major modifications to existing surface water management license, submitted after June 30, 2017 and June 30, 2021, shall use plate WM 2.1- Future Conditions and plate WM 13.1- Future Conditions​, respectively.

These new Future Conditions Map Series were necessary to:

  1.  Account for conditions expected during the lifecycle of new structures;

  2. Provide an appropriate tool for long-term infrastructu​re and site planning;

  3. Ensure the resiliency of current and future infrastructure investments by addressing future flood risk (resulting fro​m rising groundwater table, projected sea level rise, and expected increases in rainfall intensity) in the design and licensing of surface water management systems in Broward County; and

  4. Advance the resiliency standards and investments needed across the region, ultimately protecting both public and private infrastructure, preserving the quality of our environment, reducing flood insurance premiums, and ensuring a vibrant and competitive economy. 

Future Conditions Average Wet Season Groundwater Elevation Map​

​ ​In May 2017, the Broward County Board of County Commissioners enacted Ordinance No. 2017​-16 amending Section 27-200 (b) (5) a. 3. b) of the Broward County Code of Ordinances ("Code") to read:

“Antecedent conditions: Ground water and surface water stages antecedent to a design event shall be the higher of the average wet season water levels or the applicable control elevations. plate WM 2.1 may be used for determining the average wet season ground water levels for use in calculating a design event for existing projects, except for applications for major redevelopment as defined in Section 27-192 or for a major modification to a surface water management license. plate WM 2.1 - Future Conditions shall be used for determining the average wet season ground water levels for use in calculating a design event for new applications for a surface water management license, applications for major redevelopment of existing sites, and applications for major modifications to existing surface water management licenses submitted after June 30, 2017."

In addition, Ordinance No. 2017-16 amended Section 27-19, Definitions, of the Code to read:

Major redevelopment means construction activities which involve the demolition or removal of the principal structure on a site or of more than fifty percent (50%) of the impervious surface of a developed area on a site. Major redevelopment also means minor redevelopment with the cumulative expansion of developed area greater than or equal to twenty-five percent (25%) of the existing developed area of a site or greater than or equal to two (2) acres over a period of ten (10) years.

The definition of "major development" was amended to correct a typographical error and to clarify that either the demolition or removal of the principal structure on a site or the demolition or removal of more than 50% of the impervious surface of a developed site qualify as a major redevelopment.

The Resilient Environment Department, as the local planning agency for the Broward County Comprehensive Plan, and the Broward County Planning Council, as the local planning agency for the Broward County Land Use Plan, held public hearings on March 23, 2017, and April 27, 2017, respectively, at which time it was recommended to the Board of County Commissioners that the proposed Ordinance was generally consistent with the Broward County Comprehensive Plan and Land Use Plan.

The Plate WM 2.1 – Future Conditions map represents the expected future average wet season groundwater elevations for Broward County. The average is based on model outputs for the months of May through October over the period of 2060-2069. The models used are The Broward County Inundation Model and the Broward County Northern Variable Density model, both developed by the United States Geological Survey (USGS) and MODFLOW based. The future conditions that are modified in the models are both precipitation and sea level rise. The future precipitation pattern is based on the Center for Ocean-Atmospheric Prediction Studies (COAPS) downscaled Community Climate System Model (CCSM) global model and represents an increase of 9.1% rainfall fro​m the base case of 1990-1999 (53.4 inches/year to 58.2 inches/year). Sea level rise was based on the United States Army Corps of Engineers (USACE) National Research Council Curve 3 (NRC3) curve which equates to an increase of 26.6 inches to 33.9 inches to the future period from 1992 levels. Final groundwater elevation results are presented in the North American Vertical Datum of 1988 (NAVD 88).​​​

Currently, Broward County is in process of updating the Plate WM 2.1 – Future Conditions map with latest sea level rise projections for 2070 planning horizon. The updated draft pdf map can be found here​ and an interactive version showing the updated draft and existing map (adopted in 2017) can be found here​.  


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​Future Conditions 100-yr Flood Elevation Map​

In June 2021, the Broward County Board of County Commissioners enacted Ordinance No. 2021-33 amending Section 27-200​ (b) (5) a​. 3. c) of the Broward County Code of Ordinances ("Code") to read:


“Flood protection: The lowest habitable building finished floor elevation shall be above the 100-year flood elevations, as determined from the most appropriate information, including: federal flood insurance rate maps; the 100-year flood elevation map, ​plate WM 13.1; the 100-year flood elevation map, ​plate WM 13.1 – Future Conditions; the site-specific post-development 100-year, 3-day flood stage; or 100-year flood elevations established by previously approved basin studies for local water control districts with self-contained water management systems. However, nonresidential buildings may be constructed at lower elevations if they are shown to meet the Federal Emergency Management Agency's standards for flood proofing. Both tidal flooding and the 100-year, 3-day storm event shall be considered in determining elevations. Where a conceptual comprehensive drainage plan has been approved, each phase shall provide detailed plans and calculations indicating compliance with the approved conceptual comprehensive drainage plan (i.e., minimum floor elevations, building size, average finished grade, and the required retention/detention volume). For nonresidential buildings in areas where the 100-year flood elevation map, ​plate WM 13.1 – Future Conditions, establishes a flood elevation more than three (3) feet higher than the next highest flood elevation, as compared to the criteria above, the applicant may propose a lower finished floor elevation, provided (i) the proposed finished floor elevation is at least three (3) feet above the next highest required elevation and (ii) design documentation is prepared and sealed by a registered design professional using accepted engineering practices to demonstrate the adequacy of the proposed lower level of flood protection. The 100-year flood elevation map, plate WM 13.1 – Future Conditions, shall apply to new surface water management license applications, surface water management license applications for major redevelopment of existing sites, and surface water management license applications for major modifications submitted after June 30, 2021.”


Section 27-200 (b) (5) a. 3. e) 4) (aa), related to of the Broward County Code, related to residential construction with ten (10) or less parking spaces in Broward County, was also amended to read:

“The lowest habitable building finished floor elevation shall be at or above the highest of: (i) eighteen (18) inches above the road crown, (ii) the most appropriate 100-year flood elevations, as determined in Subsection c) above, by the 100-year flood elevation map, plate WM 13.1; the future conditions 100-year flood elevation map, plate WM 13.1 – Future Conditions; the site-specific post-development 100-year, 3-day flood stage; or 100-year flood elevations established by previously approved basin studies for local water control districts with self-contained water management systems; or (iii) the Federal Flood Insurance Rate maps.”

In addition, Ordinance No. 2021-33 amended Section 27-192, Definitions, of the Code to add the following definition:

“Lowest habitable building finished floor means the lowest floor of the lowest enclosed area of a building or structure, including a basement, but excluding any unfinished or flood-resistant enclosure, other than a basement, usable solely for vehicle parking, building access, or limited storage, provided that such enclosure is not built so as to render the structure in violation of the nonelevation requirements of the Florida Building Code or ASCE 24, Flood Resistant Design and Construction, developed and published by the American Society of Civil Engineers.”​


The Resilient Environment ​Department, as the local planning agency for the Broward County Comprehensive Plan, and the Broward County Planning Council, as the local planning agency for the Broward County Land Use Plan, held public hearings on March 16, 2021, and April 22, 2021, respectively, at which time it was recommended to the Board of County Commissioners that the proposed Ordinance was generally consistent with the Broward County Comprehensive Plan and Land Use Plan.


The ​plate WM 13.1 – Future Conditions map represents the expected future 100-year flood elevations for Broward County. The MIKE SHE / MIKE Hydro River model with assumed year 2060 conditions was used.  These conditions include: 1) a sea level rise of 26 inches, which is consistent with the United States Army Corps of Engineers High estimate for year 2060 (Southeast Florida Regional Climate Compact, 2015); 2) 100-year, 72-hour storm design storm rainfall depth developed by multiplying the current conditions design storm depth by a factor of 1.13, based on the Broward County DDF Change Factor Ensemble Analysis (Yin, Li, & Urich, 2019); and future conditions land use. The model also used the highest of the current conditions groundwater elevation and the future conditions groundwater elevation. Final 100-year flood elevation results are presented in the North American Vertical Datum of 1988 (NAVD 88). Plate WM 13.1 – Future Conditions map​ will be one of the tools used to determined appropriate finished floor elevations for residential and commercial structures in Broward County. ​​