After receiving reports of discolored water in a Chelsea Creek tributary, the Iowa Department of Natural Resources has traced the issue back to Martin Brower, a McDonald's distribution center in Mason City.
According to a release from the DNR, Martin Brower employees said they hosed a spilled milkshake ingredient into a storm water intake Monday morning.
From there, the contaminated water made its way through the underground storm water system and into a tributary of Chelsea Creek on the southwest side of Mason City, tingeing it the color of milk.
The DNR release stated the affected area is a couple hundred yards long and lies along a popular walking and biking area.
DNR staff took water samples at the site. Those initial field tests "showed dissolved oxygen and pH levels were normal, and ammonia levels were low," the release said. Based on those results, the spill isn't believed to pose an immediate hazard to children or pets in contact with the water.
"The company must clean up and remove the impacted water from the stream," the DNR release said.
The cleanup process wrapped up Wednesday, said DNR Environmental Specialist Senior Jeremy Klatt.
"I don't think there was anything, or at least, not much living in that little section of that tributary, but Chelsea Creek will have bluegills, stuff like that in there, catfish ... but where this spill impacted was before Chelsea Creek," Klatt said. "They (Martin Brower) did get a contractor out there to take care of it all... They went in there with like a vacuum truck to suck all that water out, so they did remove everything before it made its way to Chelsea Creek."
A representative of Reyes Holdings, Martin Brower's parent company, relayed the following response regarding the spill: "Martin Brower is partnering directly with the Department of Natural Resources to address this issue. We can confirm this does not present a threat to the local water system."
As of Thursday afternoon, Martin Brower did not return request for additional comment regarding whether training protocols were in place to avoid incidents like the one on Monday.
Additional water samples have been sent to a lab for further testing. DNR staff monitored the cleanup, the release said, and will consider enforcement action.
Melanie Mergen is Local News Editor for the Globe Gazette. You can reach her at firstname.lastname@example.org.