Agricultural runoff has harsh impact on environment

Nutrients in manure and synthetic fertilizers deplete oxygen in streams while fecal bacteria are posing health risks

Hugh Trimble has photos of two catfish. One, caught at Indian Lake, is healthy, sleek and silvery, weighing a full 14 pounds. The other, from a Lake Loramie tributary in Mercer County, is scrawny and yellowish with lip and anal tumors and parasites growing out of its flesh.

Trimble of the Ohio Environmental Protection Agency pointed to the photo of the sickly fish. “This is a result of oxygen stress, we think.”

At the dawn of the environmental movement 40 years ago, “water pollution” brought to mind images of industrial chemicals flowing out of a factory drainage pipe directly into a waterway. Today, experts say, a large percentage of water pollution should conjure up a more pastoral image: that of a soaking rain pounding a farm field and sending rivulets of storm water snaking into ditches, creeks, rivers and lakes.

It may seem benign, but agricultural runoff can be loaded with nitrogen and phosphorus, nutrients in manure and synthetic fertilizers. In excessive quantities they deplete oxygen in streams and, with fecal bacteria, make waterways unfit for recreational use and harmful to aquatic life.

Global warming aside, agricultural runoff is one of today’s biggest environmental threats. A 2000 study by the U.S. EPA found that agriculture was responsible for nearly half of the impairment to rivers — far more than other sources, including urban runoff and storm sewers.

Nutrient runoff is in some ways harder to stop than industrial pollution, officials say, because it’s difficult to trace its source — or, more likely, multiple sources.

“That’s a lot harder because that’s like death by 1,000 cuts,” said project director Nathan Holscher of Cincinnati-based Rivers Unlimited, which aims to protect and restore Ohio rivers.

The U.S. Department of Agriculture says nitrogen runoff from the Upper Great Miami Watershed, which includes most of Shelby and Logan counties and parts of several others, contributes significantly to the dead zone far downstream in the Gulf of Mexico. Experts say the dead zone, with an average size over the past five years of 6,000 square miles, is caused when nutrients, particularly nitrogen, spur an overgrowth of oxygen-depleting algae. It’s so severe it threatens the Gulf fishing industry.

Despite the Upper Great Miami’s distance from the Gulf, the Agriculture Department in November said it was one of 41 priority watersheds in 12 states eligible to split $320 million over the next four years to help farmers implement practices that “prevent, control and trap” nutrient runoff. Such practices include the creation of buffer strips and construction of above-ground structures to store manure and storm water runoff.

Unfortunately, Ohio EPA environmental specialist Greg Buthker said the region won’t be able to obtain the funds this year because of layoffs among area soil and water conservation staffers who would recruit the farmers.

The Ohio EPA is working on an assessment of water quality on the watershed, having tested water in 26 sub-watersheds in 2008 and 2009. Preliminary results show that almost two-thirds of the sub-watersheds failed to meet state and federal standards for recreational use because of fecal bacterial contamination, while 16 percent didn’t meet standards to support aquatic life. The conditions appear to be killing aquatic insects in the ecosystem, the Ohio EPA found.

Such contamination also can sicken humans. Recreational users could get sick if they ingest tainted water, or get infections in cuts exposed to bacteria.

Bacteria can also quickly contaminate drinking water aquifers if it seeps in through fractures in the bedrock, said Ohio EPA spokeswoman Heather Lauer

In 2000, at least seven people died in Walkerton, Ontario, and about half the town’s 5,000 residents were sickened when E. coli got into the drinking water. “There are still people on dialysis because of kidney damage,” Lauer said.

Despite these concerns, Buthker said farmers often resist implementing eco-friendly practices that impact their bottom line. “We’ve got our work cut out for us to get some better practices to keep the sediment on the farm. If the farmers don’t want to cooperate, there’s nothing we can do. It’s a free country.”

In Ohio, there’s no numeric limit for nutrient loading. The Ohio EPA doesn’t regulate farmers, although it monitors nearby water quality.

“The Farm Bureau’s strong,” Buthker said.

At the Ohio Farm Bureau Federation, Larry Antosch said his group’s 235,000 members support measures to keep fertilizer out of the water. He said farmers favor “flexible” programs tailored to their operations, but not “one-size-fits-all” regulatory solutions.

“If you had one number (of allowable nutrient runoff) for the state, you may be setting a standard that’s unrealistic for the more productive parts,” said Antosch, the bureau’s senior director of environmental policy.

While he acknowledged nutrient runoff is a problem, Antosch said bacterial contamination isn’t always due to livestock feces. He said the state has done little of the expensive DNA testing that would be needed to trace bacteria to its source — livestock, wildlife or failing septic systems.

Antosch said farmers have been receptive to a nutrient trading program run by the Miami Conservancy District since 2006. The program credits municipal wastewater treatment plants for nitrogen and phosphorus reductions if they pay for best-practices projects at farms upstream. Dayton, Englewood and Huber Heights are among the participating communities.

Douglas “Dusty” Hall of the conservancy district said farmers are competing for the funds. The program aims to reduce nutrient discharges by 380 tons over the life of 99 projects to be funded.

Holscher of Rivers Unlimited said data remains sketchy on nutrient levels in the Lower Great Miami Watershed. The group launched a project March 21 to sample and analyze water monthly through November in Hamilton County, looking for fecal coliforms, nitrogen and phosphorus.

“While we’ve seen much improvement in water quality (since the first Earth Day in 1970), we have real reason to be concerned about nutrient loading,” Holscher said. “Until we see more data, the report cards are going to have to be incomplete.”

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