The U.S. Environmental Protection Agency (EPA) released the results of the first comprehensive survey looking at the health of thousands of stream and river miles across the country, finding that more than half—55%—are in poor condition for aquatic life.
The 2008-2009 National Rivers and Stream Assessment reflects the most recent data available, and is part of EPA’s expanded effort to monitor waterways in the U.S. and gather scientific data on the condition of the nation’s water resources.
EPA partners, including states and tribes, collected data from approximately 2,000 sites across the country. EPA, state and university scientists analyzed the data to determine the extent to which rivers and streams support aquatic life, how major stressors may be affecting them and how conditions are changing over time.
Findings of the assessment include:
- • Nitrogen and phosphorus are at excessive levels. 27% percent of the nation’s rivers and streams have excessive levels of nitrogen, and 40% have high levels of phosphorus.
- • Streams and rivers are at an increased risk due to decreased vegetation cover and increased human disturbance. These conditions can cause streams and rivers to be more vulnerable to flooding, erosion and pollution. Approximately 24% of the rivers and streams monitored were rated poor due to the loss of healthy vegetative cover.
- • Increased bacteria levels. High bacteria levels were found in 9% of stream and river miles making those waters potentially unsafe for swimming and other recreation.
- • Increased mercury levels. More than 13,000 miles of rivers have fish with mercury levels that may be unsafe for human consumption.
EPA plans to use this new data to inform decision making about addressing critical needs around the country for rivers, streams, and other water bodies. This comprehensive survey will also help develop improvements to monitoring these rivers and streams across jurisdictional boundaries and enhance the ability of states and tribes to assess and manage water quality to help protect water, aquatic life and human health. Results are available for a dozen geographic and ecological regions of the country.