The Iowa Department of Natural Resources (DNR) is investigating manure released from a cattle feedlot about 10 miles west of Guthrie Center to a tributary to David’s Creek last week.

Owner of the 14,000-head-capacity beef feedlot, Matt Van Meter, reported the manure release at 3:34 p.m. Oct. 2, about eight hours after discovering a break in an irrigation pipe. Van Meter estimates 200,000 gallons of liquids from a solids settling basin were released, but the amount is uncertain because he’s unsure when the pipe broke.

A DNR environmental specialist tested ammonia levels in the runoff and water quality in the stream Thursday night and Friday. Field tests showed ammonia levels of at least 10 parts per million in the runoff from the feedlot, which is high enough to cause a fish kill. However, it was raining Wednesday night, stream levels were high and field tests did not show elevated ammonia levels in the stream.

Friday, the DNR checked the stream for 10 miles below the feedlot and did not find any dead fish. The Van Meter feedlot has a national pollutant discharge elimination system (NPDES) permit which allows facilities to discharge pollutants under certain conditions, such as heavy rainfall, if the permit conditions are followed.

The DNR is checking records and investigating the incident to determine if the facility was operating according to NPDES permit conditions. However, the DNR expects to take enforcement action on failing to report the manure release within six hours of discovery. DNR may take additional enforcement action depending upon results of the investigation and laboratory results from stream samples.