EPA has disapproved Vermont’s 2002 total maximum daily load (TMDL) for phosphorus in Lake Champlain. In its January 24, 2011, decision, the agency concluded that certain aspects of the TMDL did not satisfy federal requirements. Specifically, EPA found that the TMDL did not provide sufficient assurance that phosphorus reductions from polluted runoff will be achieved, nor did it provide an adequate margin of safety to account for uncertainty in the analysis.

EPA will now work with the state to prepare a new TMDL for the parts of Lake Champlain addressed in Vermont’s 2002 TMDL. Lake Champlain is bordered by Vermont, New York and the Canadian province of Quebec. The lake is 120 miles long, with a surface area of 435 square miles and a maximum depth of 400 feet. The watershed is roughly 8,234 square miles and drains nearly one-half of Vermont’s land area. New York’s TMDL for phosphorus in the lake was separately approved by EPA and is not affected by this action. According to EPA, it will seek to involve New York in the developmental aspects of Vermont’s TMDL. See EPA Press Release, January 24, 2011.