ELKHORN — A water sample taken at a utility sink in Elkhorn prompted the city to immediately take its Lakeland Water Treatment plant offline.
In June, Elkhorn sent out a notice to residents explaining a quarterly test found excessive amounts of radium in Elkhorn's water supply -- more than five times the state limit.
"I think a lot of people are concerned about it, really," said local resident Nancy Hinson. "I know a lot of people have gone out and bought bottled water so that they don't have to drink the city water."
Utilities Director, John Murphy, believes a sampling error is to blame.
"Our water is safe to drink," he said. "We're gone through all the equipment, making sure it was working properly."
Samples taken since have come back normal. However, the Lakeland plant is still offline as the DNR awaits more results.
Meanwhile, Elkhorn is relying on its two other treatment plants.
"We go to extremes to provide good, quality, safe water," Murphy said.
Elkhorn is among 11 community water systems out of compliance with Wisconsin radium regulations. Among them Waukesha, Sussex, and Pewaukee are all taking steps to reduce radium -- Waukesha, with the plan to divert water from Lake Michigan.
To be in compliance, water systems need to average below the state standard over four quarters. This is why cities serving water that meets standards can still be out of compliance after the violating test was taken.
The DNR says, right now, all communities provide water that meets radium standards.
"Several of the different communities around here have applied treatment. Some of the communities have done new wells," explained Jesse Jenson of the DNR.
Jenson says radium occurs naturally in rock formations.
"When rain falls down into the landscape, it filters into the ground," Jenson said.
The concern is not short-term exposure, but over a lifetime.
"It has been linked to bone cancer, so it is something that we do take very seriously," Jenson said.