The figures above present the nitrogen and phosphorus goals that the Bay Program has set for each major Bay tributary, and the individual state goals within each tributary.
It also presents the estimated nutrient loads for 1985, the original baseline for measuring nutrient reductions, and loads for 2000. (Some columns may not add up due to rounding.)
The Clear Skies reduction is the estimated benefit to the Bay if Congress passes the Bush administration’s Clear Skies legislation, which would require steep reductions in certain power plant emissions. If the bill does not pass, the 8 million pound reduction would have to be made up by additional reductions within the rivers.
The figures are based on computer model estimates of the level of nutrient reductions—combined with new sediment reduction goals—needed to meet new water quality criteria that have been developed over the past three years.
The criteria was developed for three parameters: dissolved oxygen, water clarity and chlorophyll a (a measure of algae). The criteria establish measurable water quality conditions that are needed in different parts of the Bay and its tidal tributaries to protect fish, shellfish, underwater grasses and other aquatic life.
The EPA published the criteria as official water quality guidance at the end of April. Jurisdictions with tidal waters—Virginia, Maryland, Delaware and the District of Columbia—will use them as the basis for enforceable water quality standards over the next two years.
In the meantime, states by next April will write “tributary strategies” which will outline the specific actions needed to meet the nutrient and sediment reduction goals in their portion of each tributary.
Unlike the Bay Program’s past nutrient goals, it is the water quality standards that are the ultimate objective, not the nutrient and sediment reductions themselves. That means the figures presented here are best estimates of what is needed to meet those standards. As more information becomes available, the figures may be adjusted up or down.
For any area of the Bay which does not meet its water quality standards by 2011, an enforceable cleanup plan, known as a Total Maximum Daily Load, will have to be developed and implemented.
Once the water quality standards are attained, continued nutrient and sediment reductions will be needed to offset the impacts of future growth in the watershed.
The final water quality criteria guidance is available on the Bay Program’s web site, www.chesapeakebay.net