Total Maximum Daily Load (TMDL) Program

The Total Maximum Daily Load (TMDL) program, established under Section 303(d) of the Clean Water Act, focuses on identifying and restoring polluted rivers, streams, lakes and other surface water bodies. TMDLs are prepared for waters identified as impaired on the 303(d) list in the Integrated Report.

Information about TMDLs and water quality monitoring are organized by large watershed. The watersheds are shown in the map to the right. Watershed names are linked to pages with further information. Ohio typically focuses on  watersheds in preparing TMDLs.

What is a watershed?

A watershed is the area of land that drains into a lake or stream. Watersheds can be small - like the area that drains into the creek behind your house. Or, watersheds can be large - consider all the land, streams and rivers that drain into the Ohio River or Lake Erie.



Click on the watershed labels to be taken to their respective pages.
Watersheds in Ohio

Ottawa River (Toledo area)

A TMDL is a written, quantitative assessment of water quality problems in a water body and contributing sources of pollution. It specifies the amount a pollutant needs to be reduced to meet water quality standards (WQS), allocates pollutant load reductions, and provides the basis for taking actions needed to restore a water body. 

  • More information on Ohio EPA's TMDL process can be found here.

Ohio developed a 12-step project-management-based TMDL process to accomplish TMDLs. The process builds on existing monitoring, modeling, permitting and grant programs in an attempt to establish a cycle of continuous improvement of the water quality in Ohio’s watersheds.  The process, which seeks public involvement in problem-solving and decision-making, contains four broad, overlapping phases:

  • Assess waterbody health: biological, chemical, habitat
  • Develop a restoration target and a viable scenario
  • Implement the solution: inside/outside Ohio EPA
  • Validate to monitor progress: delist or relist.

To gain the perspective of interests outside Ohio EPA, an external advisory group of about 80 people met for over a year to discuss options and recommend how Ohio should approach TMDLs. Their recommendations to the director of Ohio EPA in June 2000 addressed the listing process, how TMDLs should be developed and implemented, and how Ohio should deal with special problems such as mercury and air deposition.

Additional information about TMDLs is available on the U.S. EPA TMDL Web site.

The individual watershed pages on the website contain information on TMDL implementation projects that have been funded through Ohio EPA's Nonpoint Source Pollution grants program.  The listed projects are not all inclusive.  For more information regarding projects funded through these grant programs, see the following links:

TMDL Project Contacts 
Lewis, Jeff (CDO) Kokosing River, Licking River, Paint Creek, Big Darby Creek, Big Walnut Creek, Bokes Creek, Deer Creek, Mill Creek, Olentangy River, Scioto River (middle), Scioto River (upper), Walnut Creek (614) 644-2657
Zawiski, Bill (NEDO) Ashtabula River, Chagrin River, Euclid Creek, Lake Erie tributaries, Beaver Creek and Lake Erie tributaries, Black River, Rocky River, Cuyahoga River (lower), Cuyahoga River (middle), Cuyahoga River (upper), Grand River (lower), Grand River (upper), Mahoning River (lower), Mahoning River (upper), Nimishillen Creek, Tuscarawas River, Killbuck Creek, Sandy Creek, Sugar Creek, Conneaut Creek, Pymatuning, Yankee and Little Yankee creeks, Little Beaver Creek (330) 963-1134
Glomski, Dan (NWDO) Huron River, Old Woman Creek, Vermilion River, Auglaize River (lower), Auglaize River (upper), Blanchard River, Maumee River (lower) tributaries and Lake Erie tributaries, Other Maumee River tributaries, Ottawa River (Lima area), Powell Creek, St. Joseph River, St. Marys River, Swan Creek, Tiffin River, Mohican River, Ottawa River (Toledo area), Portage River, Toussaint River, Sandusky Bay tributaries, Sandusky River (lower), Sandusky River (upper), Beaver Creek & Grand Lake St. Marys, Mississinewa River, Wabash River (419) 373-3023
Taulbee, Rachel (SEDO) Hocking River, Monday Creek, Sunday Creek, Conotton Creek, Moxahala Creek, Muskingum River (lower) tributaries, Salt Creek, Stillwater Creek, Wakatomika Creek, Walhonding River and Muskingum River tributaries, Wills Creek, Captina and McMahon creeks, Cross, Short and Wheeling creeks, Duck Creek, Leading Creek, Other Ohio River tributaries, Yellow Creek, Other Ohio River tributaries, Ohio Brush Creek, Pine, Ice and Little Scioto creeks, Raccoon Creek (lower), Raccoon Creek (upper), Symmes Creek, Scioto River (lower), Salt Creek, Scioto Brush Creek (740) 380-5433
Jackson, Joshua (SWDO) Fourmile Creek, Great Miami River (lower), Great Miami River (middle), Great Miami River (upper), Indian Creek, Mad River, Stillwater River, Twin Creek, East Fork Little Miami River, Little Miami River (lower), Little Miami River (upper), Mill Creek (Ohio River), Whitewater River, White Oak Creek (937) 285-6029

Back to the TMDL page.

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