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Could restoring swampland fix Lake Erie algae crisis?

By Marion Renault • Oct 4, 2017 at 8:00 AM

The neon cyanobacteria swirling across Lake Erie for the past three months or so signals to scientists and farmers alike: The annual plague of toxic algae is far from cured.

"It looks like someone dumped green paint in the water," said Tim Davis, an aquatic biologist at Bowling Green State University. "We're still in the middle of the bloom. It's setting up to be the third- or fourth-biggest one in recent history."

Bill Mitsch, a world-renowned wetlands expert and Ohio State environmental-science professor emeritus, believes he has a remedy.

In a scientific paper published recently, Mitsch proposed restoring 10 percent of the swamps that once coated northwestern Ohio before pioneers drained the land for agriculture. He said that 100,000 acres of the former Great Black Swamp could be recruited to act as nature's kidneys and sponge up agricultural runoff that feeds cyclical cyanobacteria blooms.

But the revival of even a fraction of the western Lake Erie basin's marshes could be a tough sell in a region where 15,000 farmers produce hundreds of millions of dollars worth of soybeans, corn, wheat and livestock.

"That's a massive undertaking: 10 percent of the land," said Ohio Farm Bureau spokesman Joe Cornely. "It's certainly big thinking -- and there's nothing wrong with that -- but I also think that there are a lot of other ways to go about fixing the problem that are not quite so dramatic."

The Great Black Swamp's original million acres made it one of the largest swamps in North America, one that ensnared early settlers in muck and infected them with malaria, cholera and typhoid fevers. Only after settlers started draining the "oozing mass of water, mud, snakes, wolves, wildcats, biting flies and clouds of gnats and mosquitoes" did agriculture become feasible there, according to historians.

Through his ongoing research, Mitsch hopes to show farmers and landowners that they can actually save money and improve productivity by temporarily flipping part of their fields back to wetlands.

Strategically placed "wetlaculture" in the watershed, Mitsch said, would cut the phosphorus load in the Maumee River, the major waterway that flows from northwest Ohio's farmland into western Lake Erie, by 40 percent -- the 2025 goal set by state and federal officials in 2015.

Farmers in the region already are exploring and adopting practices to reach that benchmark, Cornely said. But they need hard evidence that a wetlaculture strategy wouldn't put them out of business.

"We drained the Great Black Swamp for a reason," Cornely said. "Food production needs to be a parallel goal. It's not an either-or situation. It could come down to balancing a math problem."

Construction began last month on Chris Lenhart's farm in Defiance; it's the latest addition to a network of wetlaculture test sites.

Mitsch's research will stretch from there to Buckeye Lake, down to southern Florida and west to St. Paul, Minnesota. Sites in Cleveland, Indiana and Long Island, New York, are under discussion.

At each of the sites, 28 plastic tubs of 100 gallons each form an underground grid of miniature marshes. Scientists subject the test tubs to different water flows and plant communities to assess their ability to soak up the phosphorus that otherwise would wash into Lake Erie and fuel the cyanobacteria blooms.

If the project is ready to scale up after a few years, the research will expand to a 250- to 1,000-acre prototype wetland somewhere in the Black Swamp region.

To turn the agricultural fields back into marshlands, farmers would cork the drainage tiles that help irrigate the land. After a few years, they could unplug the tiles and drain the fields back into fertilized farmland.

Still, Mitsch said, the experiments might not prove that a wetland-to-agriculture model can work. "This is an experiment," he said. "This might go on for 10 years or more."

In the meantime, farmers have a bottom line, said Lenhart, who is also a University of Minnesota hydrologist.

"You're hard-pressed to find people to take land out of production," Lenhart said. "It has to fit in with the farm system. You can't just take 10,000 acres out."

And farmers can't wait a decade or longer for results.

They're already trying to reduce algae-feeding nutrient overdoses with cover crops, injected fertilizer, buffer strips and phosphate beds, said Deb Berger, a spokeswoman for the U.S. Department of Agriculture's Natural Resources Conservation Service.

"They're motivated to do what's right. That's already happening," Berger said. "They want their farmland to be sustainable for generations to come, and they want to leave it in better condition than what they get."

Wetland remediation — although on a much smaller scale — is already an available option, said Perrysburg grain farmer Kris Swartz.

"Wetlands do a great job where they fit in. In a lot of areas, they would be difficult to integrate," said Swartz, a former president of the Ohio Federation of Soil and Water Conservation Districts.

But Mitsch argues that large-scale landscape changes are necessary -- especially because climate change is forecast to lead to larger, more-intense blooms.

"I haven't seen any viable alternatives that make much sense," he said. "They're working for a silver bullet that won't take up land. It's just not possible."

mrenault@dispatch.com

@MarionRenault

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