Human Pollution Knocks-out 42% of Natural Streams

Only one-in-four natural streams in the United States are in "good condition" according to a new report from the Environmental Protection Agency (EPA.)

The government-funded EPA produced its first (ever) study of wadeable streams in the United States in May 2006, and found that 42 percent of all streams were considered polluted or in "poor condition." Another 25 percent of streams were considered fair and 28 percent were considered good.

In the mid-Atlantic and northeastern United States 52 percent of streams were considered to be in poor condition, whereas 45 percent of streams west of the Rocky Mountain range were least polluted, the EPA concluded.

Sampling evolved during a four-year period ending in 2004. Farming and logging were found to raise nitrogen and phosphorous levels in fresh water streams, which promoted growth of plants and algae and killed aquatic life, said Mike Shapiro, EPA administrator, during a conference call.

The EPA study, Wadeable Streams Assessment (WSA,) is the first consistent evaluation of the streams that feed rivers, lakes, and coastal waters, according to the report. Alaska and Hawaii were not included, however a pilot project is underway.

Wadeable streams are shallow enough to be adequately sampled without a boat. They are essential natural resources that have been under-sampled in the past.

"This scientific report card on [United States'] streams will help citizens and governments measure the health of their watersheds, take actions to prevent pollution, and monitor for progress," said EPA assistant administrator for water Benjamin H. Grumbles.

"Small streams are connected to the overall health of a community's ecology and economy and this report underscores their importance and identifies priority work ahead," Grumbles said.

Some 1,392 stream sites were represented in the study and involved dozens of state environmental and natural resource agencies, federal agencies, universities, and other organizations. More than 150 field biologists were trained to collect environmental samples using a standardized method.

While stream conditions vary widely across the diverse ecological regions of the country, streams in the West were in the best condition. Humans, the researchers found, have a significant impact on wadeable streams. A majority of streams showed evidence of human influence along the streams, such as dams, pavement, and pastures, the EPA reported.

During the next five years, EPA will sample conditions of lakes, large rivers, and wetlands. Then the process will be repeated to provide ongoing comparisons of the state of the waters and point to possible future action.