MADISON, Wis. -- Madison's protected Cherokee Marsh is under attack from high water.

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Some local environmental experts said on Monday that rising water in the marsh is slowly killing off portions of the precious wetlands.

"You have to go out and see it," said Madison Parks Commission president Bill Barker. "You have to see the big chunks of wetlands tearing away and floating away."

"These wetlands did not evolve to be floating," said conservation resource supervisor Russ Hefty. "They're only floating because the dam or series of dams at Tenney Park back the water up into the Yahara River. These wetlands that were growing on peat, and instead of being inundated and lost immediately, floated up. Ever since that happened, they've been steadily eroding away."

Hefty said additional runoff from more development has also added to the water level, and recent heavy rains only add to the problem.

"I dread going out to look after it pops up two to two and a half feet above what it's supposed to be because I know what I'm going to see," said Hefty.

On Monday, Hefty took a boat tour of the marsh and showed a WISC-TV news crew large sections of sedge meadow drifting on the water.

"They will die off because of such small size," said Hefty. "Between the wind action and the ice action, things will get whittled away, so it's kind of like a slow death."

Hefty said at least 7 feet of marsh shoreline disappears every year. He said a least a full square mile of it has gone since the first dam was put on Lake Mendota in the mid-1800s.

"It accelerates as it gets wider and the waves get bigger," said Hefty. "It's a downward cycle."

"Ultimately, we're losing habitat that does support a wide variety of birds and other wildlife," said Hefty.

Some experts would like to see the lake level lowered on Lake Mendota, which in turn would lower the level in Cherokee Marsh, WISC-TV reported.

"Anything we can do to lower the summertime levels will enhance the growth of the plants," said Hefty. "And it will also reduce the loss when we have flood events because if you start at a lower elevation you have more storage so it won't rise up as high."

Those wetland plants also serve another purpose. They hold back silt that would otherwise wash in to Lake Mendota.

"Any silt that we can catch up in this part of the watershed, as opposed to having it travel freely to Lake Mendota has certainly got to have some sort of positive impact on the ultimate water quality," he said.

City officials will soon have the opportunity to weigh on the issue. On Tuesday night, the Madison Common Council will vote on a resolution that will, among other things, put a formal request in to the state Department of Natural Resources to review the lake level policy, something that hasn't been done since 1979.

"We can't just let this go on," said Barker. "If the high water levels of the lake are eroding and increasing the width of the upper Yahara River channel by 7 feet a year -- that's tens of acres of high quality marshland lost every year."

Hefty and Barker said that they hope this is the year for change. They said many of the groups that have an interest on the lakes have been impacted by the high water this year.

"You've got lakeshore property owners who aren't pleased about flooding or damage to their shorelines and having to rip out piers before their float away," said Hefty. "You've got boaters who've been denied a lot of recreation because of no wake orders."

Hefty said the key to making change is having everyone on the same page.

"This could be a real historic opportunity to really have the kind of discussion that maybe wasn't occurring in the past," said Hefty.

DNR officials said reviewing the lake level policy could take a year or longer.

A request to raise the level of Lake Koshkonong in the 1980s is still being hashed out in court because of opposing sides, WISC-TV reported.