EPA National Rivers and Streams Assessment: Water Condition Trends

U.S. EPA National Rivers & Streams Assessment data exports show the percentage of river and stream miles in fair condition for the 2018-19 survey period. The dataset likely contains indicator values for nitrogen, phosphorus, biological, physical, and human health metrics, with condition determined by comparing to NRSA-specific regional or national benchmarks. It includes calculated changes and confidence intervals for trends between survey cycles, such as 2008-09 to 2018-19 and 2013-14 to 2018-19.

Use Cases

• Tracking changes in nutrient pollution (nitrogen, phosphorus) levels over time based on regional benchmarks.
• Assessing biological and physical indicator condition for river health monitoring programs.
• Evaluating human health risk from water quality indicators like enterococci and microcystins.
• Analyzing national and regional trends in river and stream condition between EPA survey cycles.

Strengths

• Data originates from the authoritative U.S. EPA National Rivers and Streams Assessment program.
• Results include 95% confidence intervals for statistical reliability.
• Covers multiple survey cycles (2008-09, 2013-14, 2018-19), enabling longitudinal analysis.

Limitations

• Specific column names, row counts, and file sizes are not provided in the available metadata.
• License information is not specified for the extracted data exports.
• The dataset appears to be aggregated dashboard exports, not the underlying raw survey data.

Provenance

Source

United States Environmental Protection Agency (EPA)

Collection Method

Exports from the National Rivers and Streams Assessment Dashboard, extracted in original form.

Time Range

2008-09 to 2018-19 (multiple survey cycles)

Freshness

Metadata was last updated on 2026-04-21, but the underlying survey data is from 2018-19.

Geography

National coverage of rivers and streams in the United States.