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Contact Us

National Aquatic Resource Surveys

  • National Rivers & Streams Assessment

    • Access the NRSA 2013-2014 Report
    • Explore Results in the Interactive Dashboard
    • NRSA Field Methods Application
    • NARS Data Analysis Innovation Challenge

  • National Lakes Assessment

    • Access the NLA 2017 Final Report and Interactive Data Dashboard
    • Explore the Lakes Context Tool
    • NARS Data Analysis Innovation Challenge
  • National Wetland Condition Assessment

    • Access the NWCA 2011 Final Report
    • Environmental Monitoring & Assessment NWCA Topical Collection
    • NARS Data Analysis Innovation Challenge
  • National Coastal Condition Assessment

    • Access the newly released NCCA Report
    • Explore NCCA results in the Interactive Dashboard
    • NARS Data Analysis Innovation Challenge

The National Aquatic Resource Surveys (NARS) are collaborative programs between EPA, states, and tribes designed to assess the quality of the nation's coastal waters, lakes and reservoirs, rivers and streams, and wetlands using a statistical survey design. The NARS provide critical, groundbreaking, and nationally-consistent data on the nation's waters.

New Release

  • National Lakes Assessment 2017 Web Report
  • NARS Data Analysis Innovation Challenge
  • National Lakes Context Tool
  • NRSA Field Methods Application
  • NARS Population Estimate Calculation Tool
  • Survey Design Tool 

Learn about the National Aquatic Resource Surveys
  • Background
  • Indicators
  • Manuals
  • Map of Sampled Sites
  • Outreach Materials
Link to individual National Aquatic Resource Survey pages
  • National Coastal Condition Assessment (NCCA)
  • National Lakes Assessment (NLA)
  • National Rivers and Streams Assessment (NRSA)
  • National Wetland Condition Assessment (NWCA)
Data and Applications for the National Aquatic Resource Surveys
  • NARS Data
  • NCCA Data Dashboard
  • NLA Data Dashboard
  • NRSA Data Dashboard
  • Relative Extent, Relative Risk and Attributable Risk
  • Journal Articles
  • Applying the Data
  • Related Studies and Tools
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on September 23, 2022
United States Environmental Protection Agency

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