Jun 24, 2013

Experts: More grasslands, wetlands needed to help reduce flooding | The Des Moines Register | desmoinesregister.com



Written by
Perry Beema



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Iowans can’t control the weather, but they could do a lot more to limit how much rainfall runs off into the state’s rivers and streams and heightens flood risks, experts say.

Changes in climate and landscape — including more pavement, row crops and fewer water-absorbing acres of prairie grasses and wetlands — mean more rain and snowmelt are entering Iowa’s waters. That makes conditions ripe for severe floods like those of 2008 and 1993.

Following two devastating floods in the past 20 years, environmentalists and scientists say Iowa needs to act to address what they call the root causes of severe and frequent flooding, including tackling climate change and expanding grasslands and wetlands to absorb rain where it falls.

But state leaders have largely ignored such recommendations. The Des Moines Register’s review of conservation, stream flow and rainfall data suggests that, if anything, the problem is worse now than five years ago.

There have been some notable exceptions.

The Mark Twain National Wildlife Refuge in southeast Iowa’s Louisa County was expanded when the federal government purchased often-flooded acres along the Mississippi River after the 1993 flood.

And U.S. Agriculture Secretary Tom Vilsack has said recently that overall enrollment in all of the nation’s conservation programs is at a record high.

But participation in the hallmark conservation effort most affecting the Midwest — the Conservation Reserve Program, which pays farmers to keep some land in native grasses and out of crop production — has dropped sharply as corn prices rose. And the program faces funding cuts.

In 1993, Iowa had 2.2 million acres in the CRP. That year turned out to be the program’s peak. By 2008, acreage had dipped to 1.8 million. This spring, it stood at just 1.5 million.

“Sadly, it looks as if things are going in the wrong direction right now,” said Craig Cox, the Environmental Working Group’s Iowa-based senior vice president for agriculture and natural resources.

“Landowners can’t do much about how hard it rains, but they can do a lot to keep that water from rushing into streams and triggering flooding downstream,” he said. “Conventional conservation practices like no-till, grass buffers and wetlands can keep water on the land just a bit longer — cutting a few inches off a flood peak can keep a damaging flood from becoming a devastating flood.”

Data suggest the threat of flooding will only grow in coming decades.

An ISU study has found that despite some annual fluctuation, rainfall in Iowa has increased steadily over the past century.

Iowa State University scientist Eugene Takle and colleagues predict a 50 percent increase in Iowa’s stream flows by the 2040s as rainfall increases because of climate change.

Jan Glendening, state director for the Nature Conservancy, said her organization is restoring 2,300 acres near the Cedar River north of Columbus Junction as a demonstration project.

Iowa must do more of that if it hopes to keep water from rushing full force into swelling rivers, she said.

“Floods are among the most expensive natural disasters, resulting in billions of dollars of damages in the United States every year,” she said. “We need to stop repeating the mistakes of the past and make a conscious effort to invest in our future.”

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