Seven Sisters Dam

The first dam I visited.. Seven Sisters Generating Station is Manitoba Hydro's largest producer of electricity on the Winnipeg River in southeastern Manitoba. Located about 90 kilometres (km) east of the City of Winnipeg, it is fondly and respectfully described by engineers who designed and built it as the river's mightiest generating station. The generating station operates at a maximum capacity of 150 megawatts (MW) and can produce. Seven Sisters is a "run-of-river" design, which means that water flowing into the generating station from upstream is used immediately, not stored in the forebay for later use. The spillway at Seven Sisters is flanked to the north and south by non-overflow, concrete wingwalls. In winter, to prevent an ice buildup on the concrete of the spillway and wingwalls, which would create a pressure hazard, an air bubbler system has been installed to stop ice from forming. For the same reason, the spillway gates have been fitted with heaters.
http://www.ieee.ca/millennium/seven_sisters/seven_history.html