Limestone Generating Station is a run-of-the-river hydroelectric dam on the Nelson River approximately 750 kilometres (470 mi) north of Winnipeg in the Rural Municipality of Alexander in the Canadian province of Manitoba. It is a part of the Nelson River Hydroelectric Project.
It was Manitoba Hydro's fifth generating station to be built on the Nelson River, which flows from Lake Winnipeg to Hudson Bay and is the largest. The station was built on Long Spruce Rapids. The site is approximately 750 kilometres (470 mi) northeast of Winnipeg and east of Gillam, Manitoba and is 23 kilometres (14 mi) downstream of Manitoba Hydro's Long Spruce Generating Station.
The dam is owned and operated by Manitoba Hydro. It has ten generating units with a capacity of 1,330 megawatts and annual generation around 8.5 terawatt-hours. Although work at the site began in 1976 with a cofferdam completed in 1978, construction was suspended owing to a slowing of demand for electric power. The project resumed in 1985, with the first generating unit delivering power in 1990 and completion in 1992. Construction cost was $CDN 1.43 billion; favorable economic conditions at the time resulted in lower cost than budget.