EPA Finds a Majority of U.S. Waterways Bad for Aquatic Life

EPA Survey Finds More Than Half of the Nation's River and Stream Miles in Poor Condition

More than half of the country's rivers and streams are bad for aquatic life, according to a new comprehensive study by the U.S. Environmental Protection Agency.

"The health of our Nation's rivers, lakes, bays and coastal waters depends on the vast network of streams where they begin, and this new science shows that America's streams and rivers are under significant pressure," said Nancy Stoner, acting assistant director of the Office of Water. "We must continue to invest in protecting and restoring our nation's streams and rivers as they are vital sources of our drinking water, provide many recreational opportunities, and play a critical role in the economy."

The 2008-2009 National Rivers and Stream Assessment, released this week,  reflects the latest statistics available and is part of the EPA's effort to monitor and gather data from the thousands of miles of waterways in the U.S.

The EPA, partnered with states and tribes, collected data from approximately 2,000 sites across the nation and then analyzed the collected material to determine the extent to which rivers and streams support aquatic life, as well as what stressors may be affecting them and how conditions are changing over time.

The research found:

Nitrogen and phosphorus are at excessive levels, with 27 percent of the nation's rivers and streams showing excessive levels of nitrogen and 40 percent having high levels of phosphorus. Too much nitrogen and phosphorus in the water, otherwise known as nutrient pollution, can cause significant increases in algae, which harms water quality, food sources and habitats and decrease the oxygen levels fish and other aquatic life need to survive.

Streams and rivers are at an increased risk, due to decreased vegetation cover and increased human activity. The new data says such conditions can cause streams and rivers to be more vulnerable to flooding, erosion and pollution. Vegetation along rivers and streams slows the flow of rainwater, preventing the erosion of stream banks. It also removes pollutants carried by rainwater and helps maintain water temperatures that support healthy streams for aquatic life. Approximately 24 percent of the rivers and streams monitored were rated poor in this category.

High bacteria levels were found in nine percent of stream and river miles, making those waters potentially unsafe for swimming and other recreation, the data showed.

Also alarming, it was discovered more than 13,000 miles of rivers have fish with mercury levels that exceed the limits safe for human consumption.

The EPA said it will use the new data to further address the needs of rivers, streams and other bodies of water throughout the U.S.

Survey results are available for a dozen geographic and ecological regions of the country.