SIOUX CENTER, Iowa – The Iowa Department of Natural Resources (DNR) traced a fish kill in a tributary of the Floyd River to Sioux-Preme Packing Company, which is just south of Sioux Center, Iowa.

The agency said Sioux-Preme is the likely source of the discharge causing the fish kill, but the investigation is ongoing. DNR staff found elevated ammonia levels and thousands of dead fish, including game fish, for at least nine miles downstream from the plant, the agency said. Fisheries staff conducted a second count of dead fish on Oct. 29 and Oct. 30.

Sioux-Preme is addressing the problem. The agency said the company hired a contractor to pump water, pooled in a tributary, to the affected stream. DNR staff will monitor the cleanup. The agency also plans to pursue enforcement action and fish restitution.

The DNR was alerted to the problem after a resident noticed stressed fish in the stream over the weekend, the agency said.