CEDAR RAPIDS — Ending two farming practices would reduce harmful nitrates in Iowa’s rivers and streams by 10 to 20 percent in just one year, predicted Chris Jones, a University of Iowa research engineer speaking at the Iowa Ideas conference Friday.

Farmers should stop tilling their land in the fall because it leaves soil exposed to erosion longer and avoid planting crops in flood plains, Jones said during the conference that was created and hosted by The Gazette this week.

“It’s difficult for me to understand why these things continue,” he said. “If we could do those two things, we would have a 10 to 20 percent reduction in one year.”

The Iowa Department of Agriculture doesn’t track whether Iowa farmers till in spring or fall, but there’s been a more than 6 million-acre increase in no-till farmland since 1987, the agency reported. The ag department does not know how many acres of Iowa flood plain are being farmed, Spokesman Dustin VandeHoef reported Friday.

Jones’ suggestions came during a panel discussion of new research and ideas about improving Iowa’s water quality. Two water quality panels Friday brought together researchers, state officials, legislators and agricultural groups.

The big goal is reducing nitrates flowing into the Mississippi River, where they are creating an oxygen-deprived dead zone in the Gulf of Mexico. The 2008 Gulf Hypoxia Action Plan called for Iowa and other Midwest states to cut nitrogen and phosphorus loads in the Mississippi River by 45 percent.

“Have we moved the needle at all?” Gazette columnist Todd Dorman, who moderated the panels, asked Adam Schnieders, water quality resource coordinator for the Iowa Department of Natural Resources.

“Slightly,” Schnieders said. “Right now we’re getting more confidence in the metric systems to measure that.”

More municipal wastewater treatment plants have created plans to upgrade their systems to remove nitrates and Iowa is seeing a growing number of water quality projects — both good signs Iowa may see improved water quality, Schnieders said. One effort would restore 40 wetlands in the Cedar River basin, which could reduce flood events and filter nutrients from the river.

Those projects are fine, said Bill Stowe, CEO and general manager for the Des Moines Water Works, but he would like to see farmers ante up for the cost of removing nutrients from drinking water.

“Producers of adverse environmental impacts should be responsible for their impacts,” Stowe said. “Communities like yours and mine are spending billions of dollars. Ninety percent of the nitrogen in our water is from agriculture.”

The Water Works in 2015 sued Sac, Calhoun and Buena Vista counties for nitrates and other pollutants washed into the Raccoon River, a source of drinking water for 500,000 central Iowa residents. Water Works claimed it would have to spend millions to remove the nitrates to meet federal standards, but the lawsuit was dismissed earlier this year when a federal judge decided water quality was an issue for the Iowa Legislature.

Stowe doesn’t see lawmakers making changes fast enough.

“We, as Iowans, are beginning to believe everything is on a 100-year time frame. That is unacceptable,”

Water quality leadership may come from other areas, he said.

“I see the youth in our state, I see industry in our state going elsewhere.”

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