You wouldn't know it listening to Iowa agricultural industry groups or state ag department officials, but a new report from University of Iowa researchers makes it clear: state farm operators are doing a lousy job of keeping nitrogen fertilizer out of the Missouri and Mississippi Rivers.
How bad a job are ag businesses doing in preventing nitrates-nitrogen from seeping from their farm field drain tiles into state waterways?
In the Upper Mississippi River Basin, Iowa contributes 21 percent of the water, comprises 21 percent of the land area, but is responsible for nearly half (45 percent) of nitrate-nitrogen pollution that flows into the Mississippi River.
In the Missouri River Basin, Iowa contributes 12 percent of the water, comprises only 3.3 percent of the watershed land area, yet is responsible for more than half (55 percent) of the nitrate-nitrogen polluting the Missouri River.