The Bridge River Power Project

Photo: A. Roozeboom (?), c.1956 - TERZAGHI DAM UNDER CONSTRUCTION	In its day the Bridge River Hydroelectric Development was the largest of the power projects undertaken in BC to date, epic in atmosphere and daring in engineering, spectacular by scale and scenery, memorable as a community - and also highly destructive to the local ecology, though was little understood at the time.  Though largely forgotten today except by those who lived and worked in its place and time, the power project was probably one of the busiest times in the history of the Bridge River-Lillooet Country, and despite its obscurity in today's BC it was in its day one of the most important and largest power projects of its kind in the province's history.  From its compleition until the development of the WAC Bennett Dam on the Peace River in northeastern BC, the Bridge River power development provided the bulk of the power supply for the burgeoning growth of the post-war Lower Mainland - and for the Cold War-era aircraft plants and naval yards of Puget Sound.  In terms of pure engineering, there are few hydroelectric developments anywhere in North America - or the world - that rival it for ingenuity and technical complexity, even today.
Terzaghi Dam Bridge River Townsite Lajoie Dam Lillooet Canal & Powerhouse Penstocks Bridge River No. 1 Powerhouse Bridge River No. 2 Powerhouse Diagram of Development
Begun in the 1920s following opening of the district by the Pacific Great Eastern Railway, the project proceeded fitfully until after World War II, at which time resources were poured into development of BC's primary resources and the full development of the potential of the Bridge River-Seton basins was begun.  The project was finished by the early 1960s with the final completion of four power plants, three dams, several tunnels and penstocks, two new reservoirs in addition to the alteration of Seton Lake, and a canal distinguished by its bridging of two other watercourses - the whole framed within some of North America's most stunning mountains and canyons.
BC Archives # I-29082	This is a view of the project's No. 1 Powerhouse, taken from the site of the newer No. 2.  The powerhouse in view is actually the second on this site, and was rebuilt during the major overhaul of the whole project in the 1950s after its prededessor was damaged in a transformer fire.  It also housed the company's main operating room and offices.  Along the shore at left, in between the two powerhouses, was the townsite and community hall; just below the trees was the community beach, no longer accessible to the public although once a central part of community life.  Upon completion, the two powerhouses generated 480 MW of power, produced by xxx cu ft of water per minute plunging the 1078' (329m) through penstocks which emerge from tunnel outlets leading from the Carpenter Lake Reservoir.  Another powerhouse on the Fraser River at Lillooet and another at Lajoie near Gold Birdge bring the project's total generating capacity to 492 MW, which is 6 to 8% of current BC Hydro production.

http://www.bchydro.com/recreation/southern/southern1201.html

Basic information from the site linked above:

"Work on Powerhouse No.1 was postponed until 1946 due to the depression and war years. However, growing power requirements of the post-war era gave the project great urgency. The building was rushed to completion and the first generator was installed in1948. Three more generators were added at intervals until 1954. The plant’s total output of 180 MW was the largest source of power in the province at that time. While a second tunnel was being bored to carry water from Carpenter Reservoir, work on Powerhouse No. 2 commenced. Four generators were installed by the end of 1960. Water for the turbines of both powerhouses flows from the tunnels under Mission Mountain into steel penstocks which drop a vertical distance of 329 m (1,078 feet) down the hillside. Bridge No.1 has four penstocks—one for each turbine. Bridge No. 2 has two penstocks which split into four just before they enter the powerhouse. The Bridge River Picnic Site located between Seton Portage and Shalalth, offers picnicking and a boat launch. The Bridge River Powerhouses have a maximum generating capacity of 480 MWand an average generating capability of 2670 GWh per year — more than enough to supply the City of Victoria."