Cairo (IL) urban land and Birds Point levees breach and New Madrid floodway (MO)
Dr. Kenneth R. Olson, University of Illinois at Urbana-Champaign
The decision by the Corps of Engineers to blow up Birds Point levee on the Mississippi River south of Cairo on May 2, 2011 was a difficult and complex engineering as well as social and political problem. Rising floodwaters on the Ohio and Mississippi Rivers, increased water pressure and sand boils were erupting on the levee system surrounding the city of Cairo, Illinois posing enormous threat to human lives and properties. Although the Corps of Engineers anticipated and planned for a 500 year flood in this area by creating the New Madrid Floodway in Missouri, the flooding of agricultural farmlands to protect urban areas was a contentious trade-off and not an easy decision. The induced breach resulted in significant soil erosion as overland flow of fast moving water created deep gully fields leading to short-term production losses and reduction in future soil productivity.
The impact of the floodwaters on the 133,000 acres of farmland in New Madrid floodway appears to have been greater than anticipated as a result of the delay in opening the Floodway due to legal action. When the Corps of Engineers were given permission to open the Floodway, the Mississippi River was 4 feet higher than specified in the operational plan and the additional force of initial floodwater caused more damage to buildings and other structures and greater land scouring than was predicted. The 2011 agricultural impacts included the 20,000 to 30,000 acres winter wheat crop loss, the crop production loss from 20,000 to 30,000 acres of low lying and slow to drained soils not re-planted to soybeans, the loss of crop production from the hundreds of acres of fields with gullies and the 40% crop income loss from farmland in New Madrid floodway.
The Corps of Engineers reclamation effort could restore some of the permanently lost cropland in crater lakes and sand delta and/or create additional wetlands and wildlife habitat adjacent to the patched levees. It appears that the severe gullying of isolated cultivated fields on ridges or high.er lying bottomland soils could result in lost permanent agricultural land unless a federally funded land reclamation program is developed