"Iowa's outdated sewage treatment plants regularly dump excess pollution into rivers and streams that provide drinking water for up to 900,000 people and recreation for many more, a Des Moines Register analysis of state records shows.
Some river stretches, including the Skunk River south of Ames and Mill Creek south of Milford, carry almost nothing but sewage during dry weather. Popular fishing streams, including French Creek and Clear Creek in northeast Iowa, carry too much bacteria to be safe for swimmers or kayakers at times. So do parts of the Des Moines, Raccoon and Little Sioux rivers.
One of every five of Iowa's 1,910 city and commercial plants over the past five years discharged more pollution than their permits allowed. At least 1,111, or 58 percent, have faced at least one state enforcement action, sanctions that can include fines and orders to make improvements."