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Background Information & History of the TMDL Program



Section 303(d) of the Clean Water Act (CWA) requires states to submit lists of surface waters that do not meet applicable water quality standards (impaired waters) after implementation of technology-based effluent limitations, and establish Total Maximum Daily Loads (TMDLs) for these waters on a prioritized schedule. TMDLs establish the maximum amount of a pollutant that a water body can assimilate without causing exceedances of water quality standards. As such, development of TMDLs is an important step toward restoring our waters to their designated uses. In order to achieve the water quality benefits intended by the CWA, it is critical that TMDLs, once developed, be implemented as soon as possible.

Chapter 99-223, Laws of Florida, sets forth the process by which the 303(d) list is refined through more detailed water quality assessments.  It also establishes the means for adopting TMDLs, allocating pollutant loadings among contributing sources, and implementing pollution reduction strategies.

Implementation of TMDLs refers to any combination of regulatory, non-regulatory, or incentive-based actions that attain the necessary reduction in pollutant loading. Non-regulatory or incentive-based actions may include development and implementation of Best Management Practices (BMPs), pollution prevention activities, and habitat preservation or restoration. Regulatory actions may include issuance or revision of wastewater, stormwater, or environmental resource permits to include permit conditions consistent with the TMDL. These permit conditions may be numeric effluent limitations or, for technology-based programs, requirements to use a combination of structural and non-structural BMPs needed to achieve the necessary pollutant load reduction.

Spring 1999 Workshop

The FDEP held a TMDL workshop on March 2-4, 1999.  This meeting provided information allowing participating agencies to become more familiar with the status of the program and the program's procedures. 

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Impaired Waters Technical Advisory Committee (IWTAC)

The Florida Watershed Restoration Act clarified the Department’s authority for the TMDL program and directed the Department to develop a methodology, and adopt it by rule, that clearly defines those waters that should be included in the state’s 303(d) list of impaired waters. Given the importance of this effort, the Department elected to form a Technical Advisory Committee (TAC) to help us develop a clear, consensus-based method to define impaired lakes, streams, and estuaries. TAC members were selected based on their technical expertise in key scientific fields, rather than as representatives of special interest groups. While the resultant 303(d) list determined which waters were targeted for TMDL development, we also hoped that the list will be used to help prioritize a variety of watershed restoration efforts.

TMDL Allocation Technical Advisory Committee (ATAC)

On March 24, 2000, the Department held the first meeting of a Policy Advisory Committee (PAC) for the Total Maximum Daily Load (TMDL) Program. The intended purpose of the PAC was to address policy issues related to the TMDL Program, including those related to the 303(d) Methodology (Impaired Waters) Rule currently being developed by Department staff and a Technical Advisory Committee (Impaired Waters TAC), and the allocation of TMDLs to point and nonpoint sources. It was determined at the meeting though that the PAC would operate as an open discussion group, with a format more like public workshops and informal public meetings, rather than as a formal committee.

However, the Watershed Restoration Act of 1999 required the Department to form a Technical Advisory Committee to address issues relating to the allocation of load reductions among point source and nonpoint source contributors.  The Allocation TAC (ATAC) was therefore formed in order to develop recommendations for a report to the legislature on the process for allocating Total Maximum Daily Loads.

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Impaired Waters Rule Development Workshop (IWRDEV)

The Florida Department of Environmental Protection held a series of Impaired Waters Rule Development Workshops.  These workshops were one component of the ongoing rulemaking effort to develop a rule to identify impaired waters in Florida.  Topics included, impaired waters rulemaking, statistical methods used to evaluate water quality criteria exceedances, and biological assessment.

Impaired Waters Public Meetings on Policy Issues (IWPM)

The purpose of these meetings was to address policy issues related to the TMDL Program, including those related to the 303(d) Methodology (Impaired Waters) Rule currently being developed by a Technical Advisory Committee (TAC) and those related to the allocation of TMDLs to point and nonpoint sources.

More TMDL Info

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For more information on the development of water quality restoration goals (TMDLs), send e-mail to Erin Rasnake.

Water Quality Evaluation & TMDL Program
2600 Blair Stone Road - Mail Station 3555
 Tallahassee, FL, 32399-2400
Phone: (850) 245-8338

For information on TMDL grants, Section 319 (nonpoint source) grants, and other financial assistance for water infrastructure projects or implementation of urban or agricultural best management practices, please see our financial assistance webpage to determine what opportunities might be right for your project.

Last updated: June 30, 2016

  2600 Blair Stone Road M.S. 3500   Tallahassee, Florida 32399   850-245-8336 (phone) / 850-245-8356 (fax) 
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