Mississippi River states to effect regional coordination on water quality monitoring and planning and should facilitate stronger integration of state-level programs. The EPA has an opportunity to broker better interstate collaboration and thereby improve delivery of Clean Water Act-related programs, such as permitting, monitoring and assessment, and water quality standards development. The EPA should provide a commensurate level of resources to help realize this better coordination. One option for encouraging better upstream-downstream coordination would be through a periodic forum for state and regional water quality professionals and others to identify and act upon appropriate Clean Water Act-related concerns.

There are currently neither federal nor state water quality standards for nutrients for most of the Mississippi River, although standards for nutrients are under development in several states. Numerical federal water quality criteria and state water quality standards for nutrients are essential precursors to reducing nutrient inputs to the river and achieving water quality objectives along the Mississippi River and in the northern Gulf of Mexico. A TMDL could be set for the Mississippi River and the northern Gulf of Mexico. This would entail the adoption by EPA of a numerical nutrient goal (criteria) for the terminus of the Mississippi River and the northern Gulf of Mexico. An amount of aggregate nutrient reduction—across the entire watershed—necessary to achieve that goal then could be calculated. Each state in the Mississippi River watershed then could be assigned its equitable share of reduction. The assigned maximum load for each state then could be translated into numerical water quality criteria applicable to each state’s waters.

Regarding cooperation with the Mississippi River states on water quality standards and criteria, the EPA should develop water quality criteria for nutrients in the Mississippi River and the northern Gulf of Mexico. Further, the EPA should ensure that states establish water quality standards (designated uses and water quality criteria) and TMDLs such that they protect water quality in the Mississippi River and the northern Gulf of Mexico from excessive nutrient pollution. In addition, through a process similar to that applied to the Chesapeake Bay, the EPA should develop a federal TMDL, or its functional equivalent, for the Mississippi River and the northern Gulf of Mexico.

The actions recommended in this report will not be easy to implement. They will entail a greater degree of collaboration and compromise among interest groups, states, and agencies than in the past. They are, however, necessary if the goals of the Clean Water Act are to be realized and the Mississippi River provided a level of protection and restoration commensurate with its integral commercial, recreational, ecological, and other values.

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