Iowa’s largest water utility is restarting special equipment to remove nitrates from the water it uses from the Des Moines and Raccoon Rivers to its customers. Recently the Des Moines Water Works sued three northwest Iowa counties, arguing water from agricultural drainage districts contributes to the high level of nitrates. Des Moines Water Works C-E-O Bill Stowe, says the utility has spent over half a million dollars in recent months running its nitrate removal equipment.

The Environmental Protection Agency says nitrate levels above 10 milligrams per liter of drinking water are not safe for infants. Friday morning in Des Moines, the Raccoon River tested at almost 15 milligrams. Stowe says the utility’s nitrate removal system will make the water safe to drink.

Farm groups argue nitrate levels in Iowa rivers fluctuate with the weather and soil fertility and “are not significantly affected by fertilizer application rates or management.”