The Iowa Department of Natural Resources (DNR) is investigating a manure spill that occurred Sunday about four miles south of Eagle Grove. In the overnight hours, manure from a hog confinement building, owned by DMC Property Rentals, LLC of Humboldt, backed up into the building and then flowed into a nearby ditch. An unknown amount of manure was spilled, entering the Boone River about one mile downstream. The spill was discovered at about 9 a.m. on Monday, and the release was immediately stopped and dams were placed to contain the remainder of the spill. Normal ammonia levels were reported in the nearby drainage ditch and staff did not find any dead fish downstream. The DNR will continue to monitor cleanup and will consider appropriate enforcement action.