Clam Lake Canal - Cadillac, Michigan, USA - Vortexes, Mystery Spots, and Gravity Hills on Waymarking.com

The mystery is, that when the canal freezes over in the first part of the winter that the lakes on each side of it are unfrozen. Then when the adjacent lakes freeze, the canal remains unfrozen.

"The Clam Lake Canal displays an unusual event most winters. It is out of the ordinary of what usually happens to canals in the Northern Hemisphere of the world in the winter time where temperatures are consistently well below the freezing point. It is such an unusual event that it has been written up in Ripley's Believe-It-Or-Not books series. The phenomenon is when the canal is frozen over in the first part of the winter, the lakes on each side are unfrozen. The canal freezes over first during the winter months, while the lakes on either end of the canal are unfrozen during a typical winter in Northern Michigan. After the lakes freeze over during the mid-winter months, the canal thaws out and flows with unfrozen water.

According to Department of Natural Resources, the explanation for the canal unfrozen phenomenon concerns the physical properties of water. It starts with the fact that water is heaviest and most dense at 39 degrees Fahrenheit and lighter above and below this temperature because it is less dense. Therefore, in the early winter months, the lighter water molecules float to the top. Then as the weather gets colder the water closest to the top freezes first and turns to ice. In addition, since the canal is shallower and has less volume than the adjoining lakes it freezes quicker, and this is the reason why ice forms on Clam Lake canal before lakes Mitchell and Cadillac. As the winter advances and the temperatures drop more the lakes catch up and start the hard freezing process. The warm water of the lake under the ice is forced to leave as the ice becomes thicker on top.