Janesville water probably wasn’t contaminated
The city May 8 issued a boil-water advisory for the city’s north and east sides after a water test showed contamination with E. coli bacteria and coliform bacteria. A follow-up test showed the water was clear, and the boil-water advisory was lifted the next day.
Karen Cain, health officer at the health department, said they’ve seen no increase in any communicable diseases reported.
“That’s possibly an indication that there was no contamination,” Cain said. “We would have thought that if there was widespread contamination, we might have seen reports of people suffering from (gastro intestinal infections and E. coli infections),” she said.
“We didn’t see an increase in those reports.”
Dan Lynch, utilities director, said his department will never know what caused the water sample to test positive.
City water staff will sit down and “go over everything with everybody again, just to make sure everybody is doing everything right with the lab collection and the analysis,” Lynch said.
But everybody involved in the testing is experienced, and there is nothing apparent that anyone did something wrong, he said.
Lynch said the city received several calls from people who said they were sick, but one of those people got sick Tuesday, he said. There’s no way to tell why he or she was sick, he said.
“I’m pretty sure they were not sick from the water,” Lynch said. “What the confirmation test did was confirm there wasn’t anything there.”
If the water had been contaminated, “we’d still be having interesting conversations on a very regular basis,” Lynch said.
Grocery stores reported a rush on bottled water May 8 after the boil-water advisory was issued for about one-third of the city.
It was the first time a test indicated E. coli in city water in about 30 years, Lynch said.
E. coli comes from the intestinal tracts of warm-blooded animals, and it’s a sign that dangerous fecal bacteria such as salmonella, giardia, hepatitis and other harmful organisms might be there as well, said Tim Banwell, environmental health officer for Rock County.
The fecal bacteria can cause short-term diarrhea, cramps, nausea, headaches or other symptoms, according to the city’s advisory. These bacteria may pose a special health risk for infants, young children, some of the elderly, and people with severely compromised immune systems.
The boil-water area affected about 24,000 residents.
After the positive test, the city flushed water mains and increased chlorine levels to fight possible contamination. It took new water samples at the site of the first positive test and at four other sites in the vicinity, Lynch said.
The last E. coli alert in Janesville in the late 1970s was traced to an animal that got into the city’s water reservoir, Lunch said.
City water is tested about 70 times a month at various locations around the city, Lynch said.