Nitrogen, Phosphorus, Sediment Runoff
Said to Pollute Nearly Half of U.S. Streams
Nitrogen, phosphorus, and sediment runoff are smothering fish and polluting nearly half of the nation's streams, according to a survey on the health of streams released by the Environmental Protection Agency.
In a statistical Wadeable Streams Assessment of 1,392 streams randomly selected to represent a variety of ecological conditions in the 48 contiguous states, 42 percent of stream miles were in poor condition, 28 percent of stream miles were in good condition, and 25 percent were in fair condition. EPA said it did not study 5 percent of the tiny streams found in New England. Alaska and Hawaii were studied separately.
Specifically, the study found nitrogen, phosphorous, and streambed sediment runoff in combination with soil erosion, tree removal, and paving of land to be "most widespread" stressors across the country and in each of three major regions--the eastern highlands, the plains and the lowlands, and the West. . . .
High levels of nitrogen and phosphorus stimulate growth of oxygen-depleting algae, degrading water quality because a lot of organisms cannot survive under low oxygen levels.
Among the findings, EPA concluded that water quality in the eastern highlands was the worst and the West's water quality was the best; human activity, such as bulldozing trees to pave roads, was degrading water quality; and agricultural runoff containing high levels of nitrogen and phosphorus from manure and other fertilizers was "smothering" aquatic life.
And there's really nothing else to say, is there?