National Water-Quality Assessment (NAWQA) Program
Article and supplemental material in Journal of American Water Resources Association
Ranking and Confidence Intervals for Top 150 Watersheds with highest delivered yields to the Gulf: Which watersheds are in the top 150? Which watersheds are not in the top 150? Which watersheds cannot be reliably placed in or out of the top 150?
Frequently Asked Questions
U.S. Geological Survey
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