MAYNARD, IOWA — An un-used Northern Iowa hog confinement building that sat empty for years was demolished, but high levels of ammonia present in the structure were released into a stream causing a fish kill.
Late Saturday, Aug. 5, the Iowa DNR received a call reporting dead fish on a tributary of the Little Volga River east of Maynard in Fayette County.
Sunday DNR staff found dead fish and elevated ammonia levels in the unnamed creek. The fish kill was traced to an unused hog confinement building owned by Raymond Forsyth Farms Corporation of Maynard.
A contractor demolished the building Friday, allowing 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 Manchester DNR field office. “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.”
The building owner had contractors excavate contaminated soil and remove contaminated water. By midday Monday about 350,000 gallons of contaminated water had been pumped from the stream.
Mostly dead minnows, suckers, dace and darter with a few game fish were found along the small creek. 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.
DNR is conducting a fish count Monday and continues to monitor the cleanup. DNR may seek appropriate enforcement action and fish restitution.
