14) Seven Sisters Falls Generating Station

Seven Sisters Falls Generating Station

Listen to recorded audio by clicking the audio button on the left.

The area was settled by homesteaders well before the construction of the hydro dam and powerhouse. The Winnipeg River in this area consisted of seven nearly identical falls along a 2 1/2 mile stretch of river. The falls looked so much alike that they were called sisters. They were given girl’s names: Helen, Maude, Mary, Ruth, Katherine, Nora and Jean. The dam is built on the fifth fall, with the sixth and seventh visible downstream. The upper five falls or sisters are flooded. A private consortium, the Northwestern Power Company, a division of the Winnipeg Electric Street Railway Company was granted the rights to develop hydro electricity here in 1923. The dam was built in two stages. The first stage, began in July of 1929 and featured the construction of a powerhouse. A rock filled cofferdam was constructed, and concrete poured just downstream to form a control dam and a powerhouse. Work progressed on the dam, powerhouse, town site and transmission lines to Winnipeg over the next two years. Gravel for concrete was excavated from pits at Shelley, northwest of Whitemouth, and brought here by rail. The dam, dikes and the first half of the powerhouse were completed in 1931. Generators 1, 2 and 3 went on line between June and August of that year. The town site consisted of about 25 houses. As one came into the town site, they would see the Northwestern Railway tracks beside the road. At the first bend was a street called "Frog Alley" going behind the present-day dike. There were houses here, and a sawmill owned by Paul Sigurdson at the end, where Natalie Lake now is. Across the town site road was a large car garage for the residents. This garage later was converted into the present-day curling rink, with two sheets of ice, now operated by the Seven Sisters Community Club. Just north of the garage was the community hall, and then an outdoor skating rink. A Chinese laundry was located just off Frog Alley. The large building north of this marker post was a Hudson's Bay store with living quarters, a two-room school, post office, company office and library. The store closed around 1965, and the post office was moved to the main town of Seven Sisters. A large building behind the main building was the locomotive shed, later the bus garage. The outline of the big doors could be seen in the stucco of the south facing wall. The upper floor in this garage was used initially as a high school, and then as a church room. It was the home of the Seven Sisters Community Club. The building fell into disrepair, and was demolished in 2015. The first house (now gone) in the present-day town site was a duplex, with one unit being an infirmary, looked after by local doctors and nurses. The first doctor was Dr. Reid.

The great depression and World War II brought the construction progress to a halt for over 15 years. Stage two began later, in 1948, three years after World War II had ended. Inevitably, the war had delayed progress in the province's development, but during that time the demands for electricity had increased and more energy was needed. The tail race, carrying the water away from the turbines, was widened and deepened to increase efficiency. Also, the second half of the power house was built between 1947 and 1949. This was called the "second construction", providing a much-needed boost to the local economy. Units 4, 5 and 6 came online between 1949 and 1952. The dikes were built up to their present levels, and water levels increased to form the fore bay; an artificial lake called Natalie Lake. The lake was named after the daughter of the chief engineer of the Northwest Power Company. Old Pinawa generating station, built in 1906 on the Pinawa Channel was shut down September 26, 1951, forcing all the Winnipeg River's water to flow through the turbines at Seven Sisters. This is the largest generating  station on the Winnipeg River, at 150 megawatts. Seven Sisters was operated by the Winnipeg Electric Company until 1952, when all of its assets were sold to the Manitoba Hydro Electric Board (Manitoba Hydro). The rail line had outlived its usefulness, and was dismantled in 1956.

When Seven Sisters had reached 50 years of age in 1979, a major six-year rehabilitation project was conducted to extend its productive life another 50 years. Manitoba's winter with its freeze-thaw phenomenon had caused serious concrete deterioration and it became necessary to repair the generating station's north dam, to build a concrete structure to link the powerhouse to the north dyke, and to repair the powerhouse, spillway and sluiceway structures. In the late 1980s, the station's electrical and mechanical equipment was also upgraded.

A monument at the generating station was added in 2006 in commemoration of the 75th anniversary of hydroelectric dam.

Additional Details

Civic Number: N/A   l    Amenities on Site: Walking Trail; Parking  l    Building on Site: Yes

The construction of a generating station is an enormous task that takes many years of planning and building. Thousands of workers were involved in building the Seven Sisters dam during stage one in the late 1920s and early 1930s (Manitoba Hydr

Rock-filled cribs were placed in the river to form a wall around the area to be drained dry. This area, called a cofferdam, is where the Seven Sisters Generating Station was eventually built (Manitoba Hydro)

Ariel view of the Seven Sisters dam.  *Photo courtesy of George Penner*

Workers built the generating station with the Winnipeg River's turbulent waters rushing close by (Manitoba Hydro)