Agricultural practices that contribute to nutrient pollution came in for severe criticism at a Midwest regional roundtable Monday hosted by the Environmental Protection Agency and Army Corps of Engineers to gather input on defining “waters of the U.S.” under the Clean Water Act.

The virtual roundtable, the first of 10 to be held through June 24, featured community environmental activists, a builder, a sewer district CEO and others, including an Iowa organic dairy farmer and a University of Iowa engineering professor, both of whom said much more needs to be done to address nutrient runoff from farms and animal feeding operations.

None of the speakers at the roundtable represented farm groups, who have expressed frustration with the way the roundtables have been organized, including the lack of transparency about which interests would be represented.

In a letter to EPA and the Corps last fall, the Waters Advocacy Coalition, which includes the American Farm Bureau Federation and a wide range of commodity groups, said the format for the roundtables "allows the EPA and the Army to dictate who is allowed to participate in this important stakeholder process" and questioned how the information would be used.

Two panelists in particular on Monday's roundtable took a harsh view of modern production agriculture. 

“We have an unregulated industry in agriculture that needs policy and regulations to bring it in line with other societal needs,” said Larry Weber, an engineering professor at the University of Iowa. He said despite efforts through the state’s voluntary Nutrient Reduction Strategy, runoff of phosphorus and nitrates has continued to increase. 

And Iowa organic dairy farmer Francis Thicke, a former national program leader for soil science at USDA, said “agriculture contributes a whole lot of pollution – most of it, we could say – but we’re pretty much exempt, and we don’t have the political will to do anything about it. Unless we have the political will to regulate agriculture, we’re not going to get very far.”

Weber said farmers in Iowa are overapplying nitrogen, including synthetic fertilizer and manure, by about 100 pounds per acre, or about 2.5 billion pounds annually. Research shows “the nitrate load leaving Iowa has doubled since 2000 during a period when we are supposed to be reducing load by 45%,” he said in an email to Agri-Pulse following the roundtable.

The NRS, which is “based on purely voluntary approaches, is a complete failure,” Weber said in the email, adding, “We will not solve this issue in Iowa without regulating the application of commercial fertilizer and livestock manure.”

The 2013 NRS has a goal of reducing nutrient runoff by 45% by 2035. But Weber said it’s likely that nutrient loads will continue to increase over the next 20 years and likely will double again. 

Iowa contributes 29% of the total nitrogen load to the Gulf of Mexico, more than any other state, Weber said. Without Iowa's contribution, he said the nitrogen load to the Gulf would be decreasing.

Construction of “green infrastructure” that can capture nutrient runoff cannot keep up with ag intensification, Weber said during the roundtable, mentioning an $8.5 million project to build wetlands whose impact was undercut by more than 8,000 miles of subsurface tile drainage built in the same watershed.

“The impact of the tiled drainage far exceeds the benefit of the green infrastructure,” he said.

EPA and the Corps have proposed returning to their pre-2015 interpretation of WOTUS — prior to the ultimately unsuccessful regulatory rewrites made by the Obama and Trump administrations. The agencies plan to try to come up with a long-lasting definition once that proposal is finalized, but their intentions are complicated by the Supreme Court’s decision to take up a Clean Water Act case involving the regulation of wetlands under the CWA.

Republicans and industry groups have urged EPA Administrator Michael Regan to temporarily stop working on the latest proposal until the Supreme Court rules, but Regan has maintained that it’s important to keep working on it so the agencies can quickly adapt their definition to conform to the court’s ruling.

EPA Administrator Michael Regan discusses WOTUS and more in the most recent episode of Agri-Pulse Newsmakers.

The comment period on that proposal closed in February and none of the feedback from the roundtable can be used to inform the agency’s final decision.

The next roundtable is scheduled for May 23. 

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