DES MOINES, Iowa — Nitrate levels remain elevated in both major metro rivers. The Des Moines River measured more than 11 milligrams per liter on Thursday. The Raccoon River is currently around 9 mg/L, though it exceeded 10 mg/L.
The Central Iowa Water Works nitrate removal system has been operating on and off since January 6, an unusual occurrence during the winter months, when nitrate levels are typically lower.
The ongoing concerns come months after the U.S. Environmental Protection Agency removed seven river segments from Iowa’s impaired waterways list. That reconsideration included portions of the Des Moines and Raccoon Rivers, which were initially listed as impaired before the EPA reversed course last summer…