Freshwater pollution by nitrogen, phosphorous costs U.S. $4.3 bln annually

WASHINGTON, Nov. 12 (Xinhua) -- Pollution by phosphorous and nitrogen isn't just bad for lakes, streams and other bodies of fresh water, it's also bad for Americans' pocketbooks, according to researchers at Kansas State University.

The researchers calculated the money lost from that pollution by looking at factors like decreasing lakefront property values, the cost of treating drinking water and the revenue lost when fewer people take part in recreational activities like fishing or boating.

They found that freshwater pollution by phosphorous and nitrogen costs government agencies, drinking water facilities and individual Americans at least 4.3 billion U.S. dollars annually. Of that, they calculated that 44 million dollars a year is spent just protecting aquatic species from nutrient pollution.

Freshwater pollution impacts individuals on a level as basic as how much they spend on bottled water, said Walter Dodds, professor of biology at K-State.

"We are providing underestimates," Dodds said. "Although our accounting of the degree of nutrient pollution in the nation is fairly accurate, the true costs of pollution are probably much greater than 4.3 billion dollars."

The research team looked at U.S. Environmental Protection Agency data on nitrogen and phosphorous levels in bodies of water throughout the country. Nitrogen and phosphorous are nutrients that are applied to plants as nutrients.

Dodds said that the majority of this type of pollution is from non-point sources -- that is it's not flowing into a lake or stream like sewage outflow coming from one pipe. Rather, the nitrogen and phosphorous are reaching the water from various points, such as, for example, runoff from row crop agriculture across the surrounding countryside.

The research appears in the Nov. 12 on-line issue of Environmental Science and Technology. Dodds said he anticipates the research being used by policymakers because it documents the extent of the nutrient pollution problem in the United States and one facet of why it matters.