Wastewater utilities, municipalities and states will need to comply with stringent new requirements for nitrogen, phosphorus and sediment under a strict new “pollution diet” announced by the Environmental Protection Agency on Dec. 29.

The “diet,” known as the Chesapeake Bay Total Maximum Daily Load (TMDL) establishes a legally enforceable plan to ensure that six states and the District of Columbia meet the new requirements established to restore the Chesapeake Bay to health by 2025. The jurisdictions affected are Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia and the District of Columbia.

Critics have charged that the cleanup of the Bay has been historically slow and ineffective, and environmental advocates such as the Chesapeake Bay Foundation have called for EPA to develop a TMDL with teeth to force states to take steps to improve water quality, or face penalties.

The TMDL calls for a 25% reduction in nitrogen, 24% reduction in phosphorous and a 20% reduction in sediment. The TMDL�which sets Bay watershed limits of 185.9 million lbs of nitrogen, 12.5 million lbs of phosphorous and 6.45 billion lbs of sediment per year�is designed to ensure that all pollution control measures to fully restore the Bay and its tidal rivers are in place by 2025, with at least 60% of the actions completed by 2017.

The plan, which was released Dec. 29, addresses what the agency identified as “deficiencies” in draft plans submitted by the jurisdictions in September.

Among the changers to the jurisdiction plans, are more stringent nitrogen and phosphorous limits at wastewater treatment plants, including on the James River in Virginia; plans to pursue state legislation to fund wastewater treatment plant upgrades, urban stormwater management and agricultural program; and plans to implement a new stormwater permit to reduce pollution in the District of Columbia.

EPA says it will oversee each of the jurisdictions’ programs to make sure they implement the pollution control plans, remain on schedule for meeting water quality goals and achieve their two-year milestones. This oversight will include program review, objecting to permits and targeting compliance and enforcement actions as necessary to meet water quality goals.

Chesapeake Bay Foundation President William Baker praised EPA for moving forward with “a historic change in how government will restore water quality in local rivers, streams and the Chesapeake Bay.” But he added that EPA should keep jurisdictions’ feet to the fire. “It is essential that EPA [will] stand firm and impose consequences if the states and the District of Columbia do not achieve the 2009 milestones due to be met by 2011.”