Lac Vieux Desert, a 6.6 square-mile lake on the Michigan-Wisconsin border, is the headwaters of the Wisconsin River. The Lac Vieux Desert Band of Lake Superior Chippewa Indians have a number of homes and tribal property on the Lake's north shore. Most drinking water is obtained from wells drilled in unconsolidated glacial deposits. A gravel layer at or near the bedrock surface is the most productive aquifer on tribal property.
Water quality of Lac Vieux Desert is a concern for tribal members. To assess general water-quality conditions, water samples were collected at three sites on the lake in March 1996 and at 10 sites in October 1996. Profiles of pH, dissolved oxygen, specific conductance, and temperature indicate that the lake is well mixed in the fall but not when the lake is ice covered in winter.
Between 1913 and 1995, the minimum and maximum daily recorded lake levels were 1,679.28 feet (in 1925) and 1,682.16 feet (in 1951) above sea level. Since the early 1950's, the annual minimum lake-level has been lower and less variable than before the 1950's. Although the level of Lac Vieux Desert is regulated, historical levels show year-to-year fluctuations that reflect transient changes in precipitation amounts.
