TMDL STRATEGY FOR THE GREAT LAKES

The U.S. Environmental Protection Agency (EPA) and the Great Lakes States have begun a process to identify the goals, objectives, processes, and key is sues related to the development and implementation of Total Maximum Daily Loads (TMDL) for the open waters of the Great Lakes (www.epa.gov/glnpo/lakemich). TMDLs for the lakes are required under the Water Quality Guidance for the Great Lakes System (40 CFR Part 132, Appendix F) and in response to the listing of the open waters of each of the Great Lakes by one or more states under Section 303 of the Clean Water Act. Despite overall reductions in pollutant loads to the Great Lakes over the past 20 years, certain pollutants still resul t in lake impairments. Specifically, fish consumption advisories for PCBs, mercury, and certain banned pesticides have resulted in the listing of the open waters of the Great Lakes.The open waters of each of the Great Lakes generally appear on State section 303(d) lists with 2013 typically specified as the date for TMDL completion. If, prior to 2013, the state assesses the water body and determines that, based on air pollution controls and ot her mechanisms, the water is making suitable progress toward the attainment of water quality standar ds in a reasonable timeframe, the state would be justified in deferring the date for completing TMDL development for a specified time increment. Under this approach, the phase-out period actually lasts as long as air pollution and other controls continue to apply (until the water body achieves the applicable water quality standards), and TMDL development could continue to be deferred for the listed water as long as reasonable progress toward achieving water quality standards continues to be made. If reasonable progress ceases, however, the state would initiate TMDL development by the date specified for that water in its section 303(d) list or other relevant document. This paper documents options to build on the pollution reduction efforts that have been completed for the lakes and to guide the development of TMDLs for each of the Great Lakes.