Jan 27, 2011

EPA Disapproves Vermont's TMDL for Lake Champlain

Action followed reconsideration after Conservation Law Foundation challenged approvel in court

After a careful review, the U.S. Environmental Protection Agency (EPA) disapproved Vermont’s 2002 water quality plan that set phosphorus targets for discharges into Lake Champlain. Following this action, EPA intends to work closely and collaboratively with the state to develop a new plan for reductions in phosphorus from sources in Vermont. Elevated levels of phosphorus cause algae blooms and other water quality problems in Lake Champlain. Today’s action follows EPA’s reconsideration and withdrawal of its 2002 approval of the plan. The Conservation Law Foundation had challenged that approval in federal court.

EPA’s decision concerns Vermont’s 2002 Lake Champlain Phosphorus TMDL, a technical document that establishes the Total Maximum Daily Load for phosphorus in the lake. The TMDL is a pollution budget for an impaired water body, which identifies the pollutant loads that may be contributed by various sources at levels that will restore and maintain water quality. Under the federal Clean Water Act, TMDLs must meet certain requirements.

In the decision announced this week, EPA concluded that certain aspects of Vermont’s 2002 phosphorus TMDL for Lake Champlain did not satisfy federal requirements. EPA found that the TMDL did not provide sufficient assurance that phosphorus reductions from polluted runoff would be achieved, and it did not provide an adequate margin of safety to account for uncertainty in the analysis. EPA will now begin working closely with Vermont environmental officials to prepare a new TMDL for the parts of Lake Champlain addressed in the 2002 TMDL. EPA said that during this process, it will ensure ample opportunity for public input.

With or without the 2002 TMDL in place, Lake Champlain remains impaired and in need of restoration. Water quality monitoring data clearly indicate that significant work is needed to reduce phosphorus to the levels necessary to protect the lake. In the past, some observers have speculated that a new TMDL could result in stricter pollution limits for wastewater treatment plants within the Lake Champlain basin, but Curt Spalding, administrator of EPA’s New England office, cautioned that, “It is too early to know what effect a revised TMDL will have on permits for wastewater treatment plant discharges or storm water discharges. This will become clearer as the TMDL is developed.”

Although this disapproval does not apply to the New York portion of the Lake Champlain TMDL (which was approved separately from the Vermont portion in 2002 and was not contested), EPA will seek to involve New York in the development of any aspects of the new Vermont TMDL that might affect the New York TMDL, including any updates to the lake modeling work used to develop the phosphorus loading capacity of the lake.