Impaired Waters & TMDLs

TMDL Requirements

The Florida Department of Environmental Protection’s Division of Water Resource Management uses a comprehensive approach to protecting Florida water quality involving basin-wide assessments and the application of regulatory and non-regulatory strategies to reduce pollution. The Total Maximum Daily Load (TMDL) program is the heart of this comprehensive approach. (From the FDEP website). Note: both FDEP and EPA refer to the water body segments and/or their contributing area as "WBIDs."

The MS4 permit requires permittees address any TMDL(s) that was established by FDEP (or that was adopted by the EPA and verified by FDEP) at the time the MS4 permit was issued. A permittee is only responsible to take part in TMDL program activities (planning, monitoring, improvements, etc.) if its MS4 discharges into the water body with a TMDL. Thus, for any given permit cycle, it’s likely only some Palm Beach County MS4 permittees will have TMDL activities.

Existing TMDLs in Palm Beach County

The MS4 Cycles 1 and 2 permits were issued when no TMDLs were in place, and therefore, there were no required TMDL activities.

When the MS4 Cycle 3 permit was issued (3/2/2011), there were 7 TMDLs in place. The relevant MS4 permittees (stakeholders to the TMDL) addressed the TMDLs during the period of the Cycle 3 permit and all required activities are complete.

The MS4 Cycle 4 permit was issued on 9/8/2016, and at that time, there were 3 TMDLs in place. These are listed in the table below.

For locations of all TMDLs in Palm Beach County View FDEP Interactive TMDL Map.

During Year 1 of the permit cycle, permittees with TMDL responsibilities (stakeholders) must develop a prioritization plan for the TMDLs it is party to. For Cycle 4 of the PBC MS4 permit, 8 permittees are TMDL stakeholders of one or more TMDLs. These permittees submitted their prioritizations during Year 1 and all were approved by FDEP. The 8 permittees, their prioritized TMDL, and the associated schedules are presented below.

Impaired Water Body Segments

Although no action is required under the MS4 permit for impaired water bodies or TMDLs in the planning stage, this information is still tracked by the MS4 Group.

Within Palm Beach County, both FDEP and EPA have identified impaired WBIDs. Both a map and a list of the impaired WBIDs (April 2017) are available.

FDEP also develops a Planning List for the development of TMDLs. The current Planning List identifies TMDL development through 2022. As of November 10, 2017, seven water bodies in Palm Beach County were on the Planning List. Three of those water bodies are included in a Reasonable Assurance Plan (RAP) being coordinated by FDEP for the Loxahatchee River (North Fork - WBID 3226D, NW Fork – WBID 3226A and SW Fork – WBID 3226C). The RAP effectively removed these three WBIDs from the TMDL Planning List, leaving just four Palm Beach County water bodies on the List. In January 2019, FDEP added Lake Osborne to the TMDL Planning List.

FDEP On-going Waterbody Assessments

FDEP’s on-going assessment program for waterbody impairment divides the state’s waterbodies into 5 Basin Groups, with each group cycling through a 5-year assessment cycle. The 5-year cycle includes planning, monitoring, preliminary evaluation, public meetings, final evaluation, and Secretarial (state) adoption of the verified lists. Within Palm Beach County, four of the Basin Groups are represented. The third assessment cycle began in 2012. Below is the Assessment Cycle 4 schedule that FDEP published in 2018.

For Additional Information

FDEP has developed a web-based geographic tool, NNC Tracker, to view applicable numeric nutrient criteria for waterbodies throughout the state.

A number of presentations have been given on TMDLs throughout the state. The following list includes several that may be of interest. Click on the title to download a PDF of the presentation.