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National Aquatic Resource Surveys

  • National Lakes Assessment

    • Access the NLA 2022 Report and Interactive Data Dashboard
    • Explore the Lakes Context Tool
  • National Rivers & Streams Assessment

    • Access the NRSA 2018-19 Report and Interactive Dashboard
  • National Wetland Condition Assessment

    • Access the NWCA 2021 Report and Interactive Data Dashboard
  • National Coastal Condition Assessment

    • Access the NCCA Report and Interactive Dashboard

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 Wetland Condition Assessment 2021 Report -new!
  • National Lakes Assessment 2022 Report - new!
  • Aquatic Resource Monitoring and Assessment Dashboard- new!

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
  • Access the NARS Interactive Data Dashboards
  • Relative Risk/Attributable Risk
  • Journal Articles
  • Applying the Data
  • NARS and Related Tools
  • Related Studies
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on May 8, 2025
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