SNC-Lavalin has won a $587 million contract to design and build the Waneta Expansion, a 335-megawatt hydroelectric powerhouse near Trail, B.C.

The SNC-Lavalin contract is the design-build part of a $900 million project being undertaken by a partnership between two B.C. Crown corporations, Columbia Power Corporation and Columbia Basin Trust, and energy company Fortis Inc., which has 2.1 million gas and electricity customers in Canada.

The expansion will see a second powerhouse built where the Pend d'Oreille River meets the Columbia River, about half a kilometre from the Canada-U.S. border.

SNC will do the engineering, design and construction of the facility, supply and install two turbine-generator units and do related work.

The project "will require extensive environmental management plans, including special measures for the protection of sturgeon," SNC said.

Engineering and construction has begun and the plant is expected to produce power in the spring of 2015.

Provincially owned BC Hydro bought a third of the Waneta dam and original generating facility from Teck Resources in March for $825 million.

At the time, BC Hydro said that Teck often sold the vast majority of its surplus power to the United States. When the company decided to sell assets, BC Hydro moved to buy the Waneta interest to avoid the risk "that Teck would have sold to another party that could have diverted all of the power to the United States."

The Waneta Expansion is the third project undertaken by Columbia Power and Columbia Basin Trust.

The other projects were the building of the 185-megawatt Arrow Lakes Generating Station and the 120-megawatt Brilliant Expansion, both near Castlegar, B.C. The Crown corporations also own the 145-megawatt Brilliant Dam and Generating Station, bought in 1996.

Fortis holds 51 per cent of the Waneta Expansion and the two Crown corporations 49 per cent.

B.C. is facing increased demand for electricity as the population grows. Demand for electricity could rise by as much as 40 per cent over the next 20 years, BC Hydro has said.