Watershed Databases are compilations of sediment chemistry, tissue chemistry and sediment bioassay data. Analytical results from different studies in a specific watershed are collected and combined in a uniform relational database structure, creating a "Watershed Database" to query against. ARD uses Query Manager Watershed Databases as a foundation for understanding environmental contamination, evaluating and assessing ecological risk and damage, and building a GIS "Watershed Project". The Watershed Database and GIS Mapping projects are comprised of Query Manager data, a GIS project which provides context for mapping and analyzing contaminant data with relevant spatial data layers, and MARPLOT (a free companion mapping application).

Watershed Databases and Maps are available for download at this time:

• Anacostia River, Washington DC
• Calcasieu Estuary, Louisiana
• Charles River, Massachusetts
• Christina River, Delaware
• Delaware Estuary, Mid-Atlantic Coast
• Elizabeth River, Virginia
• Hudson River, New York
• Kalmazoo River, Michigan
• Newark Bay, New Jersey
• Puget Sound, Washington
• San Francisco Bay, California
• Sheboygan River, Wisconsin
• Southern California, California
• St. Andrews Bay, Florida
• St. Johns River, Florida
• St. Louis River, Minnesota
• Willamette River/Portland Harbor, Oregon
• Vieques Island, Puerto Rico