Lake Koshkonong is a naturally occurring lake that acts as a reservoir in southern Wisconsin. Its size was augmented by the creation of the Indianford Dam in 1932, making it one of the larger lakes in the state. The lake lies along the Rock River, with the river acting as both the primary inflow and the primary outflow for the lake. Lake Koshkonong begins downriver from Fort Atkinson, with the large majority of the lake located in southwestern Jefferson County. Small portions of the lake extend into southeastern Dane and northern Rock counties. After the creation of the Indianford Dam, which was built several miles down the Rock River from Lake Koshkonong, the lake has had a surface area measuring . It remains very shallow with an average depth of and a maximum depth of . The dam itself measures high and with a length of at its crest. Maximum capacity of the reservoir is . Both dam and reservoir are owned and operated by Rock County. History and etymology The currently accepted spelling "Koshkonong" was first used by Doty in 1844. An often repeated claim that has been recently disputed is that the meaning of the name is "the lake that we live on." A more accurate approximation may be "where there is heavy fog," or "where it is closed in by fog." Current thinking suggests that the modern spelling is a contraction of various names given to the region by white settlers in the early 19th century. They incorporated various pronunciations of the region from various surrounding tribes, including "Kashkawanung" from the Ojibwe, "Coscahoenah" from the Menomini, and "Kuskouonog" from the Potowatomi. This theory is supported by the fact that these name forms seem to share Algonquian language patterns, despite describing a Winnebago (Siouan) village. More evidence disputing the older name translation is that the name seems to have described a Winnebago village on the shores of the lake, with the name being extended to the body of water at a later date. This spelling of the lake's name gained legitimacy after surveying efforts in the area codified this interpretation in the 1830s and 40's. Fort Koshkonong, a fort of some importance to the United States during the Black Hawk War, was named in accordance with this convention. The fort was active before the Rock River was dammed, when the area was a cattail marsh with the Rock