MADISON, Wis. -- The quality of the city's water has become an issue in the mayor's race after several wells were shut down in the last year, due mostly to high levels of manganese.

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Reports of high levels of manganese in water wells surfaced in May 2006. Ten months later, Madison Water Utility Manager David Denig-Chakroff received a five-year contract extension. The mayor imposed strict water improvement requirements in the contract, and said he would make a change if they weren't met.

Engineering studies have recommended a $2 million filter for Well 29, but no final decision has been made. It would take a while to install the filter as well, and until then, Mayor Dave Cieslewicz is trying to calm concerns of the public.

"First of all, we have water that is clean and safe. We've done over 2,000 tests for manganese (and) none of them consistently exceed the EPA guidelines for manganese, so we know our water is in good shape," Cieslewicz said.

His mayoral opponent, Ray Allen, has made the water issue central to his campaign, saying the mayor was slow to respond.

"They knew as early as 2004 they had water quality issues. Nothing was done. Certainly I'd be more transparent with the public," Allen said.

The water quality efforts are ongoing, with water filter tests conducted throughout late winter on Well 29. The mayor appointed former Department of Natural Resources Chief George Meyer to the Board of Water Commissioners in December.

"The strategies we've put in place to deal with the manganese issue were put in place before the first word was written in the press about it," Cieslewicz said.

But Allen said that's not enough.

"I certainly would be overseeing these departments a lot better, because it's about protecting the public, whether water or public safety, he's not protecting the public," Allen said.

The mayor said improvement takes some time.

"I think the public confidence is starting to be rebuilt. It'll take time; it's a big ship and does take some time to turn around," Cieslewicz said.

In Madison, the average water bill is about $200 every six months. But to pay for infrastructure improvements to help handle quality issues, the Water Utility has requested a significant 15 percent rate hike, which the Public Service Commission will decide in May.

Madison's water bills would remain about 40 percent less than the statewide average, according to PSC records.