Clam Lake Canal

In 1873, George A. Mitchell paid $2,000 ($42,700 today) to purchase a 40 acres (16 ha) strip of land between Little Clam Lake (since renamed Lake Cadillac when the village of Clam Lake was similarly renamed) and Big Clam Lake (since renamed Lake Mitchell, for George's nephew and partner, William W. Mitchell). The strip already connected these lakes via the small Black Creek, which Mitchell envisioned as an efficient transportation route for logs once the canal was constructed.[4][5]

Mitchell first persuaded the Grand Rapids and Indiana Railroad to change their original route layout between the lakes to be redirected to go to the eastern end of the Little Clam Lake in the southeast corner of Wexford County, Michigan.[5] He then formed the Clam Lake Improvement and Construction Company and developed a canal there by widening the stream. There was a construction permit taken out as was required by the state of Michigan.[6] Mitchel widened the .33 miles (0.53 km) long connecting stream to some 20 ft or 6.1 m. The main reason for the canal's development was to be able to float logs from one lake to the other and collect fees for the usage of the waterway.[7] The logs were taken to the railroad and sawmills for processing into lumber.[8] The Clam Lake Canal has been widened additionally six times to about 50 ft or 15 m wide and is used in the present time as a recreational passage between the lakes for the local boaters.[9]

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.[3] The phenomenon is when the canal is frozen over in the first part of the winter, the lakes on each side are unfrozen.[3] 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.[3] After the lakes freeze over during the mid-winter months, the canal thaws out and flows with unfrozen water.[3]

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. The warm water moves toward the canal, thawing the canal and causing the canal water current to flow. It stays open for the length of the winter. On rare occasions, when the temperature goes below zero Fahrenheit, there will be some ice formed on the shoreline of the canal.[10]

• 
  January 1890 – Clam Lake Canal flows in winter months while the lakes on each side are frozen over
• 
  February 1900 – Clam Lake Canal flows, Lake Cadillac and Mitchell are frozen with thick ice on top
• 
  11/21/2008 – Widened Clam Lake Canal is frozen, but the lakes on each side are open and unfrozen
• 
  12/14/2008 – Lakes are frozen, while Clam Lake Canal itself is flowing and unfrozen in winter

• List of Michigan State Historic Sites in Wexford County

• Ashlee, Laura R. (2005). Guide to Michigan's Historical Markers. Ann Arbor, Michigan U.S: University of Michigan Press. ISBN 0-472-03066-3.
• Jager, Mark (1995). Mystic Michigan: Part One. Marion, Michigan: Zosma Publications. ISBN 9780967246444. Ever since the canal was constructed in the late 1880s, people have wondered why the canal freezes over when the cold weather comes, while the lakes remain unfrozen. Later, when the lakes freeze over, the canal thaws out and remains unfrozen for the rest of the winter.