Archive of the EPA National Aquatic Resource Surveys (NARS)

This data product is an archived clone as of 29 April 2025 of the U.S. Environmental Protection Agency’s (EPA) National Aquatic Resource Surveys (NARS) program, capturing all publicly available datasets, technical reports, field and laboratory manuals, and associated metadata. The NARS program conducts nationwide surveys of the condition of the United States’ rivers, streams, lakes, coastal waters, and wetlands. This clone includes data from the National Rivers and Streams Assessment (NRSA), the National Lakes Assessment (NLA), the National Coastal Condition Assessment (NCCA), the Wadeable Streams Assessment (WSA), and the National Wetland Condition Assessment (NWCA)—as well as methodological documentation supporting field and analytical protocols. The archive preserves original file structures and naming conventions from the EPA’s releases, including a copy of the web table associating each data file with its associated metadata file. This dataset is intended for users seeking a complete reproducible copy of the NARS data ecosystem for scientific analysis, educational purposes, or environmental monitoring.