| Environmental survey
rates 42% of U.S. streams in poor condition May 8 -- Forty-two percent of the shallow-stream miles in the United States are in poor condition, and only 28 percent are in good condition, according to a survey released May 5 by the U.S. Environmental Protection Agency. The Wadeable Streams Assessment is the first statistically valid survey of the biological condition of streams throughout the country, according to the EPA. The survey was based on samples collected at 1,392 sites between 2000 and 2004. Wadeable streams are shallow bodies of water that feed rivers, lakes and coastal waters. The most widespread contaminants found were nitrogen, phosphorous and streambed sediments. Nitrogen and phosphorous contamination, which result from farming operations and fertilizer runoff, are nutrients that increase the growth of algae, decrease levels of dissolved oxygen and cloud the water. Streambed sediments smother aquatic habitat and degrade conditions for fish. Stream conditions varied widely by geographic region. Western streams were in the best condition, with 45 percent of wadeable streams rated good. The worst conditions were in the Eastern Highlands - an area from New England through the Appalachian Mountains - where only 18 percent of the stream miles were in good condition.
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