The 1550MW Romaine complex is to have first units commissioned in five years but construction work on the project, on the river Romaine in the Cote-Nord region of Quebec, is not due to be completed until 2020.
La Romaine will comprise four plants - Romaine 1-4 - and each will be supplied by reservoirs, to generate a total of approximately 8TWh of electricity per year.
The commissioning schedule for the plants is Romaine-2 in 2014, Romaine-1 in 2016, Romaine-3 in 2017 and Romaine-4 in 2020.
The project budget is Can$6.5B (US$5.53B), and the peak of the long construction period is 2012-2016.
Representatives of the utility, provincial government and native peoples attended the official groundbreaking for the scheme, described as Canada's biggest construction project.
Last week the Canadian Government announced that it accepted the conclusions of the federal-provincial Joint Review Panel over the environmental assessment of the hydro power complex. The Panel had concluded that, subject to the implementation of required mitigation measures, the construction and operation of the plant was unlikely to cause significant negative environmental impact.
However, a 20-year environmental monitoring programme will be undertaken following the completion of the scheme, at an estimated cost of Can$200M (US$170M).
Launch of the construction on the project was welcomed by the Canadian Hydropower Association (CHA), which said the country has approximately 163GW of technical hydro power potential. It added that the potential is more than double the capacity already installed.
Last month Hydro-Quebec reported higher net income in 2008 compared to the previous year due to increased net electricity exports and prices.
