The Environmental Working Group (EWG) released a report that says storm water erosion is sweeping away soil across the Corn Belt at a much higher rate than the government estimates.
EWG, based in Washington D.C., says scientists tracking soil erosion in Iowa after every storm have produced highly precise soil-erosion estimates that were corroborated with aerial surveys.
Data from the 2007 National Resources Inventory, released through the USDA’s NRCS, says erosion in Iowa averaged 5.2 tons per acre per year, only slightly higher than the allegedly “sustainable” rate of 5 tons per acre per year for most Iowa soils.
Across the Corn Belt, the NRCS estimated that erosion averaged only 3.9 tons per acre per year. But data cited in EWG’s report suggests the damage is far greater.
In some areas in Iowa, recent storms triggered soil losses that were 12 times greater than the federal government’s average. (To read more, go to www.ewg.org.)