Sediment clouding the river: Getting to conversations about why

There has been a lot of attention lately on sediment, those particles of soil and other solids that float down river and can cause problems, like pollution and the filling in of Lake Pepin. The topic is controversial because taking ownership of high sediment levels means having to do something about them.

Some recent reports have placed the onus on farmers in the Minnesota River watershed and especially on new, highly efficient tiling systems that quickly rush water off the land and into streams. On Friday, at the Country Inn & Suites in Mankato, a group of more than 200 people--about half of them farmers--gathered to hear a variety of viewpoints on climate, geology, and potential solutions to runoff.

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The meeting, organized by the Minnesota Agricultural Water Resources Coalition, was interesting because it was an effort to put farmers at the center of the debate. This drew the matter into the bailiwick of Ground Level, which seeks to explore community solutions to big problems.

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A few of the presenters intimated, if not outright stated, that farmers play a minimal role in the current sediment woes of the Mississippi River, a perspective that dismays some scientists and environmentalists.

Dr. Stanley Trimble, a professor of geography at UCLA, made the case that farm-related sediment has decreased markedly since the 1930s. "In my view, farmers have done an extraordinary job," he said, partly chalking up current levels to bank erosion caused by a wet weather regime. "The stream itself is the source of the sediment," he said. In some cases, Trimble added, conservation practices themselves can change water flow patterns and cause erosion. He called this a "cruel irony."

Largely concurring with Trimble's assertions, Dr. Satish Gupta, a researcher at the University of Minnesota, added dredging to the list of culprits. "The problem is still not rightly diagnosed," he said. Gupta showed a modern-day aerial shot of the muddy Minnesota River flowing into the cleaner Mississippi alongside a similar photo from the 1930s. "The Minnesota River and its tributaries have been muddy since pre-settlement times," he said.

"I don't think erosion is due to tile drainage," concluded Gupta. "We need to do more research before we spend money we don't have."

These sentiments were more warmly received by farmers than by the environmentalists and regulators in attendance. Because it's difficult to control "nonpoint" pollution sources, change largely must come from voluntary efforts. "Facts and data are necessary, but not sufficient," said Robert Finley of the Minnesota Pollution Control Agency, from his chair at the back of the room. "Emotion plays a big part. Culture plays a big part. There is a strong ethic around voluntary compliance. I don't see that changing."

Mostly what came across at the seminar is that farmers, at least those in attendance, want to do better at controlling runoff and pollution. Case in point: According to Minnesota Farm Bureau literature, "Minnesota farmers rank third nationally in miles of Conservation Reserve Program filter and buffer strips along waterways." Still, there seems to be a ways to go.

"We need to set aside the ag versus environmentalist mindset," said Matthew Wohlman, a farmer in Renville County who serves as assistant commissioner at the Minnesota Department of Agriculture. "We need to work together. We share some common goals here."

Wohlman called on farmers to be flexible when it's shown there is a better way. "Farmers are the best stewards of the land and water. We know the challenges better than anyone else."

Toward the end of the seminar, the MPCA's Larry Gunderson spoke. "Nobody benefits if it becomes our science versus your science," he said. "We need to have mutual respect." He made a series of suggestions to farmers, including targeting priority areas, working with support networks and supporting calls for enforcement of existing laws. "We believe water quality and agriculture can both exist, " Gunderson said to applause. "You can control your own destiny."

A theme began to emerge, that by taking conservation seriously, farmers can avoid further regulation. Don Baloun, State Conservationist for the Natural Resources Conservation Service, closed the event by asking that farmers, when making their yearly budgets, include something for conservation. "Don't make that number a zero. If we are going to tile, let's be smart enough to put water quality measures in place at the same time. The right practice, the right place, the right time. It can work."

"Don't look at this globally," Baloun added. "Look at your operation and decide what works."