ANKENY, Iowa — The Iowa Department of Natural Resources says dead fish have surfaced in an Ankeny stream after 800 gallons of bad milk were improperly disposed of following by a Hy-Vee following Monday's derecho.
A stream connected to the Fourmile Creek began turning white early Wednesday morning. The DNR received reports of fish struggling near the surface of the stream as well.
"Dead fish in the tributary were mostly minnows and small gamefish," Iowa DNR said.
DNR staff and Ankeny officials traced the white color back through a storm drain to milk released at the Hy-Vee store at N. Ankeny Boulevard.
An employee at the store made an "uninformed decision" when instructing others on how to dispose of milk that had gone bad during following storms on Monday, according to a company spokesperson.
Hy-Vee tells Local 5 the store immediately began working with the City of Ankeny, DNR and a third-party environmental cleanup company to address any potential issues.
"We are covering all costs related to the cleanup," Hy-Vee said in a statement. "We also have enrolled the employees involved in environmental education training with the DNR so this does not happen again in the future."
DNR staff haven't seen any fish die from the incident, however, they said the bacteria that breaks down in organic products can use up the oxygen in the water.
In small streams, low oxygen levels can cause fish and small organisms like crayfish and insects to die.
“Materials that we think are harmless can actually be very toxic to the environment,” Ted Petersen, a DNR supervisor, said in a press release.
“When disposing of a liquid into the municipal collection system, it’s important to check with the local wastewater treatment plant or DNR field office prior to disposal.”
The DNR continues to monitor cleanup activities and check on the stream for dead fish and will consider appropriate enforcement action.
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