Developing the remaining cost-effective hydroelectric potential in Ontario is an investment that will make a modest but worthwhile contribution to expanding our low-cost, low-carbon electricity supply to meet the province’s future needs.


Up until the 1950s, waterpower resources underpinned Ontario’s electricity supply. Once the largest waterpower sites had been developed, Ontario began to add thermal generation, primarily coal along with some oil-fuelled generating stations to meet growing electricity demand. Nuclear generation, because of the clean, low-cost, abundant base-load electricity it produced, became the supplement to waterpower.

Ontario’s Long-Term Energy Plan foresees a total of 9,000 MW of hydroelectric generation by 2018. Investments should focus on cost-effective projects rather than a hard cap of 9,000 MW. Smaller waterpower projects (less than 50 MW) could be constructed on crown lands. Large-scale projects in remote locations are not always feasible due to high costs, seasonal water levels, environmental issues, land use issues and the requirement for long transmission lines.

For more information about Ontario’s hydroelectric resources and how these generating stations work please go to the following websites: