ASME-Landmark:Michigan-Lake Superior Power Hydroelectric Plant

When Francis H. Clergue and Hans von Schon designed the Sault Ste. Marie Hydro-Plant, it was to be the largest in the world in terms of the volume of water passing through its penstocks, with a power house designed to contain more turbines and more generators than any contemporary plant. At the time, only the then-recently completed Niagara Falls Power House No. 1 matched the capacity of the Sault Ste. Marie Plant.

Excavation of the plant's canal began in September 1898 and was completed in June 1902. Construction of the powerhouse began in March 1900 and was completed in 1902. It was constructed of stone and steel and is 1,340 feet long and 80 feet wide, with a total of 40 turbines installed at water level. A portion of the first floor was left vacant for prospective specialized customers and the balance was left vacant for the installation of an additional 40 turbines should they be required.

In May of 1963, the Edison Sault Electric Company purchased the plant and canal and converted the 25-cycle generating units to 60-cycle units. Altogether, the plant featured 78 horizontal turbines, each with four runners that drove 74 60-cycle generators and four exciter units that provided field current. Net plant capability was 36,000 kilowatts, generating electricity for some 50 percent of the Upper Eastern Peninsula of Michigan.

As of 2016, the plant is one of the oldest large generating stations still operating in the United States. See ASME website for more information