The Department of Natural Resources has advised against swimming in 11 lakes across the state again this week. The DNR’s Jason Palmer in the Water Quality division says the return of wildlife and agricultural runoff toward the end of the season has created an elevated risk for all types of harmful bacteria.
They look first for E. coli. “We use E.coli bacteria primarily as an indicator of conditions where we might also see other pathogens or virulent bacteria that are of human health concern,” Palmer says. He says birds in the water around the beaches have elevated the concern of possible bacteria.
“So you start thinking about when you go to the beach and you see the waterfowl that are loafing and hanging about at the park. During these time frames, it’s likely that those local sources are more of a factor,” he says. The DNR held over last week’s advisories as they say the heatwave made it unsafe for workers to take new samples.
(By Grant Winterer, Iowa Public Radio)