The history of the debate over lake levels in Madison had its beginnings in 1848 when ambitious businessman Leonard J. Farwell built a dam across the Yahara River, harnessing the flowing water to power a grist mill.

Because of that dam, Lake Mendota is today about five feet higher than its natural, historic level.

The grist mill, Farwell's Madison Mills, proved a great success, according to the history of Madison written by David Mollenhoff. For years, the imposing five-story wooden building was the city's only flour mill. One reporter, writing about the mill in the early 1850s, noted the "merry clatter'' of its grist mills, turning lathes and buzzsaws, and how it had a ''very agreeable effect on the minds of our citizens.''

Business boomed and the mill operated 24 hours a day. Farwell kept a couple of pet bears on the premises for a while and could often be seen playing with them as though they were kittens.

Though the mill proved successful, not everyone was happy with its presence. Mollenhoff said several farmers with fields near the shore of Lake Mendota watched unhappily as the rising water  from the mill's dam flooded their livelihoods.

Lawsuits against the city ensued and continued to work their way through the courts for years.

The fields weren't the only victims of Mendota's rising waters. Over the years, other landmarks have disappeared beneath the waves.

In the late 1890s, a small island called Rocky Roost rose off the shore of Governor's Island. In 1893, Frank Lloyd Wright designed a grand vacation cottage that was built on the island by his childhood friend, Robie Lamp.

The cottage was destroyed by fire in 1934 and in intervening years, the rising waters of Lake Mendota have closed over the island so that now, it is only visited by divers who can glimpse the foundations of the Wright-designed cottage in the watery gloaming.

Hidden beneath the lake at various spots around its shores are submerged gravel and sandbars that once hosted swimmers, anglers and weekend celebrants. And on the North Shore of Lake Mendota is a cave, its entrance mostly beneath the water, in which Black Hawk is rumored to have once took refuge.

Aerial photos taken over the years show how dramatically the rising level  of Lake Mendota has altered some shorelines, none more apparently than Cherokee Marsh. Russ Hefty, conservation director for the Madison Parks, said the marsh was once true wetlands split by a modest and narrow river. Now it is a lake with rare sedge meadows being eaten away, year by year, by the lapping waves.