The fish kill was traced to a discharge of egg washwater from the The Good Eggs layer operation owned by Joe Scallon of Iowa Falls.
DNR investigators found high levels of ammonia in the stream near a county road west of Mallory Memorial County Park last Friday for a pollutant source on Thursday. The egg washwater reached the stream when a tank at the facility overflowed into an underground drain tile. The tile flowed into a ditch leading to the Maynes Creek tributary.
The fish killed were mostly minnows and shiners but included some smallmouth bass. The DNR is calculating the number of fish killed and will monitor the cleanup, taking appropriate enforcement action.
(Reporting by Pat Powers, KQWC, Webster City)