A TMDL (Total Maximum Daily Load is a scientific determination of the maximum amount of a given pollutant that a surface water can absorb and still meet the water quality standards that protect its designated uses including recreation, human health, and aquatic life. Water bodies that do not meet water quality standards are identified as 'impaired' for the particular pollutants of concern — nutrients, bacteria, mercury, etc. — and TMDLs must be developed, adopted and implemented for those pollutants to reduce pollutants and restore the water body so that designated uses are attained. The threshold limits on pollutants in surface waters — Florida's surface water quality standards on which TMDLs are based — are set forth primarily in rules 62-302 and 62-303, Florida Administrative Code (FAC), and the associated table of water quality criteria. Adopted TMDL rules are included in Chapter 62-304, FAC.

The data layer depicts EPA approved TMDLs, state adopted TMDLs, and draft TMDLs. EPA approved TMDLs have been fully approved by both EPA Region 4 and the State of Florida. State Adopted TMDLS are those TMDLs that have been adopted into State Rule (62-304, FAC) but have not been approved by EPA. Draft TMDLs are those TMDLs that are currently undergoing public review, including a public workshop, and have not yet been adopted in rule. EPA approved, state adopted, and draft TMDLs are listed by Waterbody Identification units (WBID). WBIDs were created by the Florida Department of Environmental Protection for assessment purposes. Each WBID represents a unique segment, presented as a polygon, of the State’s waters.

TMDLs are listed by parameter and include: 1) Dissolved Oxygen (DO) and Nutrient TMDLs include TMDLs for the following impaired parameters Dissolved Oxygen, BOD, Nutrients, and Un-ionized Ammonia; 2) Bacteria TMDLs include TMDLs that are impaired for Fecal Coliforms; and, 3) Other TMDLs , such as Iron, Lead, and Turbidity.