NHA National Hydropower Association


Renewable hydroelectric power accounts for about 40 – 50%* of Cloverland Electric Cooperative’s power supply annually. The cooperative’s hydroelectric plant in Sault Sainte Marie, Michigan, generates about 30%* of the hydroelectric power. An additional 20%* is generated from the U.S. Army Corps of Engineers hydro plant, located in the Soo Locks.
*Percentages fluctuate monthly.

While we appreciate the interest in the history and functionality of our hydroelectric plant, we do not offer tours. Cloverland is dedicated to its mission of providing safe, reliable, and affordable electricity to its members.

Hydroelectric Plant History (PDF)

Power Canal

Aerial view of hydroelectric plantExcavation of the hydro canal occurred from 1898 to 1902. It is lined with more than 10,000 white pine timbers native to the area to strengthen and stabilize its structure.

The canal’s entrance at the east end of Ashmun Bay is controlled by four steel head gates. The canal is approximately 2 1/4 miles in length from the head gates (intake) to the hydro plant. It is approximately 24 feet deep and 200 feet wide at water level.


Construction of the landmark hydroelectric plant facility was completed in 1902. At that time, it was the second largest hydro facility next to Niagara Falls.

The hydro plant is constructed of steel and red sandstone excavated from the power canal. The plant is a quarter-mile long, 80 feet wide and has 74 horizontal shaft turbines located on the generation floor level. Each turbine has four runners (blades) that drive the 60-cycle generators. The water, which flows down the power canal, drops through gates in the turbines to make them spin, similar to a pinwheel in the wind. The turbine turns the generator rotor to create electricity.


Under ideal operating conditions, the hydro plant is capable of producing about 36,000 kilowatts (36 megawatts). Power output depends on the volume of water traveling through the power canal and the plant’s operating head. The operating head is the difference in water levels at the plant’s forebay (upriver) and the tailrace (downriver) on the St. Mary’s River. This difference is equivalent to the drop in elevation between Lake Superior and the lower Great Lakes.

At peak operation, the plant discharges approximately 30,000 cubic feet of water per second (equivalent to about 13.5 million gallons per minute).



Local architect, James Calloway Teague, designed the plant in 1899 to give the impression of power, importance and stability. The Romanesque design included three large pavilions and a double-pitched roof to counterbalance the length of the plant.

Powerful Facts

  • Hydroelectric plant with lights onThe hydro plant consists of 74 three-phase generators. Each 60-cycle generator operates at 4400 volts, 180 RPM, and 600 to 850 KVA (600 KVA can power two big box retail stores).
  • With 20 feet of headwaters falling from the upper St. Mary’s River to the lower river, rated output of the turbines is 772 to 935 horsepower.
  • Three manufacturers (no longer in existence) built the turbines. Many replacement parts are now machined in-house.
  • Canal water velocity is seven to 10 feet per second, or five to seven miles per hour.
  • A 14-person team, including nine repairmen, two electricians, a machinist, welder and manager, maintain the plant. Cloverland’s Director of Generation oversees all activities of the plant.
  • The hydro plant generates between 25 and 30 megawatts of electricity on average, or about 225 million kilowatt-hours, annually.
  • Renewable hydroelectric power accounts for approximately 50%* of our power supply. Cloverland produces 30%* and an additional 20%* is generated from the U.S. Army Corps of Engineers hydro plant. *Percentages fluctuate monthly.
  • Most of the heat needed for the building during the winter months is generated by the operating equipment.
  • The plant is allocated water every month by the International Joint Commission (IJC) for use in power generation. The IJC controls the levels of Lake Superior and the lower Great Lakes by regulating the amount of water the generating plants can use for power production.
  • The plant increases electricity production when the demand for electricity is highest (8 a.m. to 10 p.m., weekdays) and reduces production at all other times during periods of insufficient water allocations.
  • Some of the original wood bearings for the turbines are still in use today. The bearings were made from lignum vitae, a rare dense wood found in Central and South America.

Lake Superior State University Center for Freshwater Research and Education (CFRE)

  • The Center for Freshwater Research and Education (CFRE), operated by Lake Superior State University (LSSU), is located in the east end of the hydro plant. LSSU students are responsible for the day-to-day operations of the CFRE and receive valuable hands-on experience in freshwater research and fish culture. These LSSU graduates obtain jobs in fish and wildlife management, hatchery operations, ecology, and other biological sciences.
  • With the support of Cloverland Electric Cooperative and the Michigan Department of Natural Resources and Environment, the CFRE performs freshwater research and stocks fish in the St. Mary’s River.
  • The CFRE raises and releases approximately 30,000 Atlantic salmon into the St. Mary’s River each year.
  • The CFRE has been housed in a small, two-story section of the east end of Cloverland Electric’s hydro plant. CFRE will expand its research, education, and hatchery operations with a new facility to be constructed near Alford Park, on the east end of the hydro plant. Given the unique location at the nexus of three Great Lakes, CFRE is well-positioned to play an important role in increasing scientific understanding and education of Great Lakes issues. Therefore, LSSU and the State of Michigan have decided to invest in a new Center for Freshwater Research and Education (CFRE) to increase capacity in freshwater education and science to ensure that the Great Lakes remain great.
  • Visit the Lake Superior State University website to learn more about CFRE.