December 11, 2009

Researchers urge floodplain management changes

by K.C. Jaehnig

CARBONDALE, Ill. -- Removing levees and subsidizing floodplain farmers who grow water-tolerant crops could reduce flood damage to downstream cities and towns while providing a host of environmental benefits, say a group of researchers whose specialties include ecology, engineering, economics and geology.

Their argument, titled “Sustainable floodplains through large-scale reconnection to rivers,” appears today (Dec. 11) in the Policy Forum section of Science Magazine, an international weekly journal. Authors are Jeffrey J. Opperman, Gerald E. Galloway, Joseph Fargione, Jeffrey F. Mount, Brian D. Richter and Silvia Secchi

“Federal subsidies currently encourage both agriculture and development on floodplains,” says Secchi, an economist with Southern Illinois University Carbondale’s College of Agricultural Sciences.

“That means taxpayers are paying twice -- once for the tax credits and subsidies that permit farming and development and once for the disaster relief payments when they’re flooded out. We’re saying we can do better. We can manage these resources in a way that makes sense for everyone.”

Climate change, ongoing land-use shifts and deteriorating levees increase the risk of devastating floods in the coming years, the researchers say. Allowing rivers to overflow their banks in certain farmed areas would cut that risk by dispersing floodwaters, lowering the costs of both flood prevention and relief. Restored to their natural function, floodplains -- “among the planet’s most threatened ecosystems,” according to the researchers -- could once again shelter a tremendous variety of animals, birds, fish and water creatures in healthy forests and wetlands. Upstream dams that now must remain partially empty to allow for floodwater storage could direct their increased capacity to supply additional water and power.

Targeting farm fields rather than developed areas for levee removal would minimize disruption but still would have real consequences for farmers whose fields flood.

“You can’t just put that risk on their shoulders and expect them to go along because you think it’s better for the planet,” Secchi said.

The researchers therefore urge several changes in floodplain agriculture.

First, farmers could switch to timber or biomass fuel crops that can withstand flooding.

“Farmers are innovators -- they’re always trying new things,” Secchi said.

“If you give them some safeguards and compensate them for the risks they face, I think farmers would get on board.”

Compensation could come in part through redirecting subsidies farmers already receive. Instead of encouraging traditional agriculture on flood-prone lands, the subsidies could reward farmers who grow flood-tolerant crops.

A trickier recommendation involves payments to farmers from those who benefit from flood protection or greater reservoir capacity.

“We would have to figure out both who would pay and how that would work geographically because those who benefit are not in the (affected floodplain),” said Secchi, whose current research focuses on assessing the costs and benefits of changes in floodplain management.

Because natural floodplains improve water quality, increase groundwater stores, retain greenhouse gases and keep farm chemical runoff from washing downstream, farmers also might be able to get payments for these “ecosystem services.” Some funding mechanisms, such as the USDA’s Wetland Reserve Program, which offers payments in exchange for not growing crops on wetlands, and the Chicago Climate Exchange, a greenhouse gases trading group, already exist. Others would have to be created, probably at the federal level.

“It would be complex to manage, but that’s no reason not to do it,” Secchi said.

“If something’s not working -- and our current floodplain management system is clearly not working -- you should do something else.”