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National River Restoration Science Synthesis - A scientific synthesis of river restoration projects, with a searchable database. [Department of the Interior, U.S. Geological Survey (USGS), National Biological Information Infrastructure]

National Streamflow Information Program - Home page describing the operation and maintenance of 7000 streamgages, overview of the program, system for collection of streamflow data, maintaining of historic streamflow data, and available reports [Department of the Interior, U.S. Geological Survey (USGS)]