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Glossary of Terms


303(d) list The list of Florida's water bodies that do not meet or are not expected to meet applicable water quality standards with technology-based controls alone.
305(b) report Section 305(b) of the CWA requires states to report biennially to the USEPA on the quality of the waters in the state.
Best Management
Practices (BMPs)
Methods that have been determined to be the most effective, practical means of preventing or reducing pollution from non-point sources.
Biochemical Oxygen
Demand (BOD)
The amount of dissolved oxygen utilized by aquatic microorganisms.
Coliforms Bacteria that live in the intestines (including the colon) of humans and other animalsused as a measure of the presence of feces in water or soil.
Clean Water Act (CWA) The Clean Water Act is a 1977 amendment to the Federal Water Pollution Control Act of 1972, which set the basic structure for regulating discharges of pollutants to waters of the United States.
Dissolved Oxygen (DO)  The amount of oxygen gas dissolved in a given volume of water at a particular temperature and pressure, often expressed as a concentration in parts of oxygen per million parts of water.
Effluent Wastewater that flows into a receiving stream by way of a domestic or industrial point source.
Environmental Protection
Agency (EPA)
The United States Environmental Protection Agency was created in December 1970 to address the nation's urgent environmental problems and to protect the public health. The majority of DEP's regulatory programs have counterparts at the EPA or are delegated from the EPA.
Florida Department of
Environmental Protection (FDEP)
The Florida Department of Environmental Protection is Florida's principal environmental and natural resources agency. The Department of Natural Resources and the Department of Environmental Regulation were merged together to create the DEP effective July 1, 1993.
Karst An area of limestone terrain characterized by sinks, ravines, and underground streams.
Load Allocations The portions of a receiving water's loading capacity that are allocated to one of its existing or future nonpoint sources of pollution.
Load Capacity  The greatest amount of loading that a waterbody can receive without violating water quality standards.
Margin of Safety The maximum amount of exposure producing no measurable effect in animals (or studied humans) divided by the actual amount of human exposure in a population.
National Pollutant Discharge
Elimination System (NPDES)
The permitting process by which technology-based and water quality-based controls are implemented.
Nonpoint Sources (NPS) Diffuse runoff without a single point of origin that flows over the surface of the ground by stormwater and is then introduced to surface or ground waters. NPSs include atmospheric deposition and runoff or leaching from agricultural lands, urban areas, unvegetated lands, onsite sewage treatment and disposal systems, and construction sites.
Nonpoint Source Pollution  NPS pollution is created by the flushing of pollutants from landscape by rainfall and the resulting stormwater runoff, or by the leaching of pollutants through the soils into the ground water.
Organic matter  Carbonaceous waste contained in plant or animal matter and originating from domestic or industrial sources.
Pollutant Load Reduction
Goals (PLRGs)
Pollutant Load Reduction Goals are defined as estimated numeric reductions in pollutant loadings needed to preserve or restore designated uses of receiving bodies of water and maintain water quality consistent with applicable state water quality standards. PLRGs are developed by the water management districts.
Point Source An identifiable and confined discharge point for one or more water pollutants, such as a pipe, channel, vessel, or ditch.
Pollutant Generally any substance, such as a chemical or waste product, introduced into the environment that adversely affects the usefulness of a resource.
Pollution An undesirable change in the physical, chemical, or biological characteristics of air, water, soil, or food that can adversely affect the health, survival, or activities of humans or other living organisms.
STORET EPA's STOrage and RETrieval data base used nationally for water quality data storage.
Total Maximum Daily
Loads (TMDLs)
Total Maximum Daily Loads are a tool for implementing state water quality standards and are based on the relationship between pollutants and in-stream water quality conditions.
Trophic State Index Measures the potential for algal or aquatic weed growth, and is used to indicate the water quality of lakes and estuaries. Its components include total nitrogen, total phosphorus, and chlorophyll.
Turbidity The presence of suspended material such as clay, silt, finely divided organic material, plankton, and other inorganic material in the water.
Watershed Topographic boundaries which contribute or may contribute runoff to surface waters or an area of recharge.
Water-Quality Index Determines the quality of Florida's streams, black waters, and springs. Categories includewater clarity, dissolved oxygen, oxygen-demanding substances, nutrients, bacteria, and macroinvertebrate diversity.
Wasteload Allocations
Pollutant loads allotted to existing and future point sources such as discharges from industry and sewage facilities.
Water Quality Standards
State-adopted and EPA-approved ambient standards for water bodies. The standards prescribe the use of the water body (such as drinking, fishing and swimming, and shellfish harvesting) and establish the water quality criteria that must be met to protect designated uses.

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

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, 2015

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