The demolition of a hog confinement facility led to a fish kill in Fayette County over the weekend.

Someone found dead fish on a tributary of the Little Volga River east of Maynard and notified the Iowa Department of Natural Resources late Saturday (Aug. 5, 2017). DNR officials investigated the report on Sunday and found dead fish in the unnamed creek, along with elevated ammonia levels.

Investigators traced the fish kill to an unused hog confinement building that was torn down by a contractor on Friday. According to the DNR, the demolition allowed manure to flow into the creek.

“Despite the building being empty for four years, ammonia levels were high enough in the remaining liquids to kill fish,” said Tom McCarthy of the DNR's field office in Manchester. “The main message is to know what you are pumping and make sure it’s not toxic. Any liquids from an unused feedlot or confinement should be tested and properly land applied.”

Records show the confinement facility is owned by Raymond Forsyth Farms Corporation of Maynard. Contractors hired by Forsyth Farms excavated the contaminated soil and removed contaminated water. About 350,000 gallons of contaminated water had been pumped from the stream by midday Monday, the DNR said.

Mostly dead minnows, suckers, dace and darter with a few game fish were found along the small creek. The DNR found live fish, and no dead fish, downstream in the Little Volga River. Live fish were noted in the unnamed tributary after pumping ended.

Officials with the Iowa Department of Natural Resources were in the process of conducting a fish count on Monday and continue to monitor the cleanup. The DNR may seek appropriate enforcement action and fish restitution, officials said.

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