Letting Rivers Run Wild Won't Help the Midwest
Tearing Out River Levees Would Not Create Biodiversity, Just More Soggy Ground
July 23, 1999
by Dennis T. Avery
CHURCHVILLE, Va. - Even as 2 million people were recently forced from their homes along India's overflowing Ganges River, the Sierra Club said that America should learn to live with floods again.
A recent cover story in the group's magazine claims that the dams and levees in the Mississippi and Missouri Valleys don't really stop floods but merely channel the water rapidly downstream.
The environmental group wants to restore the lazy, wandering old paths of the Missouri and Mississippi Rivers. It wants more swamps and sloughs and oxbows retaining more water upstream, creating a huge set of restored wetlands.
The group recommends that we tear out our dams and levees, relocate homes and businesses that lie in the way and let the rivers do whatever the rivers want to do up and down Midwest river valleys.
It's an odd recommendation, coming at the very moment that the environmental movement is loudly criticizing the Chinese government for forcing the relocation of 1 million people to build the Three Gorges Dam (which will prevent flooding).
Now the same environmental groups want the U.S. government to relocate its own people so the country can have more flooding!
The Sierra Club's reflooding idea would also mean losing thousands of farms and huge amounts of cropland. The Wetlands Initiative, a Chicago-based organization, estimates that, without levees or dams, the big Midwest floods of 1993 would have covered 13 million acres - half what has been leveed and drained in the last 200 years.
The project would eliminate far more U.S. cropland than urban sprawl. Between 1982 and 1992, the United States expanded urban land use by 9 million acres, added 17 million acres to parks and wildlife areas and lost only 2 million net acres of cropland.
Sierra Magazine says the Midwestern flood plains represent "wetlands destroyed for agriculture."
Another viewpoint, however, is that this high-quality land was devoted to farming because of its potential for high farm yields.
There are other advantages to farming the Midwest as opposed to other regions with poorer-quality land. There are fewer wildlife species - and fewer endangered species--to put at risk in the Midwest because it had relatively few to start with.
Texas and Florida, which have warmer climates and poorer-quality land, have vastly more species. Tropical forests may well have 100 times the biodiversity per acre of the Midwest.
Tearing out river levees would not create more species, just more soggy ground. Most of the year it would be too wet even for hiking.
When George Rogers Clark led an expedition to capture a British-held fort on the Illinois frontier in 1779, he marched his men across more than 100 miles of prairie, often through water that was knee-deep.
America was unable to farm much of the Corn Belt until levees were built to protect the farmland and drain tile was installed to allow timely planting in the spring.
The Mississippi Valley does one thing superbly well: grow crops. Corn yields in the bottomlands of Illinois and Missouri produce some of the highest corn yields in the world, over 300 bushels per acre.
By comparison, Indonesia is yielding less than 20 bushels of corn per acre from its outer islands, where it is clearing tropical forest for agriculture.
Perhaps the Mississippi watershed needs additional wetlands for wildlife habitat in specific areas. It may be that some of the flood plains of the Mississippi and Missouri Rivers would make ideal places for a modest expansion of Midwestern wetlands.
But the world cannot afford to lose much of the fertile Corn Belt. The tropics have few good soils, while the middle of America has the biggest chunk in the world.
Maybe learning to live with floods again isn't such a great conservation idea after all.
Dennis T. Avery is based in Churchville, VA, and is director of the Hudson Institute's Center for Global Food Issues.