DES MOINES, Iowa (AP) – The Iowa Supreme Court has upheld a legal doctrine going back 100 years in Iowa that allows agriculture drainage districts to maintain immunity from lawsuits seeking monetary damages. The ruling today (Friday) presents an obstacle for the Des Moines Water Works, which is pursuing a lawsuit in federal court in Sioux City filed in March 2015.

The water utility for 500,000 Iowans alleges the three counties (Sac, Calhoun and Buena Vista) that oversee 10 agricultural drainage districts, should be required to obtain federal water pollution discharge permits and pay the utility more than $1.4 million it has spent for increased filtration methods to remove the nitrates from water.