The Iowa Department of Natural Resources says some of the 3,000 gallons of liquid hog manure spilled earlier this week in Mahaska County has reached the Skunk River.
The Burlington Hawk Eye reports that the spill occurred Wednesday afternoon after a valve on a manure tank loading system failed to close properly.
While most of the spill pooled on the ground, some ran downhill into a small tributary that leads to the South Skunk River. The department says the Ring Valley producer behind the spill dammed the tributary, preventing most of the manure from reaching further downstream.
The department says no dead fish have been found, but personnel are monitoring the cleanup.