The Thunder Bay Hydroelectric System is a system of four hydroelectric power plants near Alpena, Michigan. The system was originally built by the Alpena Power Company, beginning in the early 1900s. Today, the system provides recreation opportunities and clean power to residents of Michigan. It operates under a license from the Federal Energy Regulatory Commission (FERC Project No. 2404) valid through 2038. Total system generating capacity is 7,530 kilowatts. The system delivers over 32 million kilowatt-hours of clean electricity into the Midwest power grid in a typical year.
In addition to the four power plants, the system includes two storage reservoirs authorized in the FERC license for the Thunder Bay project to manage water flows through the system. The Upper South facility creates the 7,000-acre Fletcher Pond in Lachine, Michigan. Hubbard Lake covers 9,300 acres in Hubbard Lake, Michigan. Water releases from both are regulated to maintain specified seasonal water levels in the reservoirs.
Hillman, located on the Thunder Bay River near the village of the same name, is a 250-kilowatt generating station with a single vertical Francis turbine producing about 1.4 million kilowatt-hours of clean electricity per year.
Norway Point is a 4,000-kilowatt power station on the Thunder Bay River in Alpena, Michigan. Its dam creates the 1,700-acre Lake Winyah. The Norway Point facility contains two vertical Francis turbines producing about 14 million kilowatt-hours of clean electricity per year.
The Four Mile facility is immediately downstream of the Norway Point facility in Alpena, Michigan. It contains three horizontal Leffel Samson turbines and one Flygt turbine for a total capacity of 2,080 kilowatts and produces approximately 9.5 million kilowatt-hours of clean electricity per year.
The Ninth Street facility is the final facility on the Thunder Bay River, located in downtown Alpena about one mile from the mouth of the river in Thunder Bay on Lake Huron. It contains three horizontal Leffel Samson turbines with a total capacity of 1,200 kilowatts and produces approximately 7.2 million kilowatt-hours of clean electricity per year.