Lake Peigneur is located in Louisiana near the Gulf of Mexico. Before 1980, it was an approximately 10-foot deep fresh water lake with an island in the middle. Next to it, and partially under it, Diamond Crystal Salt Company maintained a salt mine, with salt being mined near the lake since 1919.
In 1980, Texaco drilled down to look for oil beneath Lake Peigneur. A little too far down. The mistake drained the entire lake like a bathtub, creating an enormous whirlpool that consumed barges, drills, and 65 acres of land. Oops.