To the editor:
Here are some interesting facts about Iowa’s water problem and the hypoxic zone in the Gulf of Mexico: Iowa is only 3 percent of the land that makes up the Mississippi Watershed. Of all the water that is in the Mississippi River when it reaches the Gulf, only 6 percent of the water has flowed through Iowa.
However, Iowa contributes 45 percent of all the nitrates that end up in the Gulf of Mexico, causing the dead zone in the Gulf.
The nitrates are difficult to remove by municipal water treatment plants and also expensive to remove.
New studies from the University of Iowa have shown that nitrates in drinking water cause more types of cancer than previously thought, including cancer of the ovaries, thyroid, kidneys, bladder and particularly of the colon and rectum.
Better agricultural practices can reduce farm field runoff and keep nitrates out of Iowa’s streams. The nitrates come from commercial fertilizer and hog manure. Iowa’s voluntary Nutrient Reduction Strategy, meant to solve this problem, is not working.
More regulations are needed.