More Than Health Damaged by Ag Nutrients in Drinking Water

Biology professor Walter Dodds, who led the study, says the researchers calculated that $44 million a year is spent just protecting aquatic species from nutrient pollution.

Dodds and the K-State researchers based their conclusions on U.S. Environmental Protection Agency data on nitrogen and phosphorous levels in bodies of water throughout the country.

The damaging chemicals - phosphorous and nitrogen - enter the environment from nonpoint sources rather than flowing into a lake or stream from one pipe.

Kansas stream loaded with sediment and agricultural runoff (Photo courtesy USGS Kansas Water Science Center)

They enter the water from various points, such as runoff from row crop agriculture across the surrounding lands, said Dodd.

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.

"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."

High levels of nitrogen and phosphorus in waters can produce harmful algal blooms. In turn, these blooms can produce "dead zones" in water bodies where dissolved oxygen levels are so low that most aquatic life cannot survive, according to the EPA.

"Excesses have been linked to higher amounts of chemicals that make people sick," the agency says on its website.

Dodds said he anticipates the K-State research will be used by policymakers because it documents the extent of the nutrient pollution problem in the United States and one facet of why it matters.

"Monetary damages put environmental problems in terms that make policymakers and the public take notice," he said. "Putting environmental problems in terms of dollars allows people to account for the actual costs of pollution."

The study appears in the November 12 online issue of the journal "Environmental Science and Technology."

Contributors to nitrogen and phosphorus pollution include:

• Overusing fertilizer - both residential and agricultural usage
• Rainfall flowing over cropland, Animal Feeding Operations and pastures, picking up animal waste and depositing it in water bodies
• Rainfall flowing over urban and suburban areas where stormwater management is not required, such as parking lots, lawns, rooftops, roads
• Discharge of nitrogen and phosphorus from wastewater treatment plants
• Overflow from septic systems

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