HULL, Iowa — The report of a fish kill Wednesday sent field staff from the Spencer office of the Iowa Department of Natural Resources (DNR) looking for a source of the pollutant in a small creek on the southeast side of this Sioux County town.
The DNR found dead fish in a small tributary of the West Branch of the Floyd River, and they traced the problem upstream to Hull Co-op Association, where an employee rinsed out chemicals Wednesday morning after spraying corn.
The rinse water containing fungicide and insecticide ran into a storm sewer, flowed under Iowa Highway 18 and entered the creek, killing some 3,600 fish, according to DNR estimates.
“While the chemical was greatly diluted, even small amounts in the parts per billion can be toxic to fish,” said Ken Hessenius, supervisor of the DNR’s Spencer office.
“With stream levels low and temperatures high, fish and other aquatic organisms are more likely to be stressed,” Hessenius said. “I would urge everyone to be careful so that chemicals and other potential pollutants don’t reach streams.”
DNR fisheries staff estimated the dead fish were mostly minnows, chubs and darters, and they were killed along 4,200 feet of stream.
The DNR said it will seek appropriate enforcement action, including fish restitution.
Parts per billion can kill fish. What effect does the drift from aerial spraying have on everything else, especially you and me?