What part of south dakota northern or southern parts. As for the southern half south of watertown there is minimal full sized vechiles driving on, mostly just quads. Lakes around the Sioux Falls area DO NOT drive on only travel on foot. I talked to a guy today who was up north waubay area and said lots of slush and water on the lakes. We are heading that way saturday to the waubay area but we plan on walking. Good Luck to you and safe travels.