Sliding island

There was some confusion last week when it was reported that an island in Wisconsin's Chippewa River broke off and came to a rest beside a bridge. It turns out the island didn't move, even though several people called a television station in Eau Claire. Given that we've seen lakes disappear in Wisconsin (near the Dells a couple years back) and dams burst in Iowa (this year), all sorts of geographical weirdness seem possible in the Upper Midwest. But I'm pretty sure an island couldn't just float away. Chicagoist posted about the story.