Mayo Lake Enhancement

The Mayo Lake Enhanced Storage Project will help us generate more renewable electricity, on average, by using more of the water available in Mayo Lake. It would require a change to our water use licence to allow us to use up to an additional one meter of water in the lake.

At first, we would drop the lower level of water we are allowed to use on Mayo Lake by 0.5 m. After three years of monitoring, we and the First Nation of Na-Cho Nyäk Dun would determine if the lower level:

can be lowered by another 0.5 m,
should stay the same, or
should be raised back to the existing licence limit.

This decision would be made based on the results of our ongoing annual monitoring studies and be made according to the environmental thresholds identified in the enforceable adaptive management plan.

This project also includes the removal of sediment in Mayo Lake.

During Phase 1, we would remove the old cofferdam remnants, which are affecting water flows – possibly as early as spring 2021.
During Phase 2, if needed after several years of monitoring, we would dredge a narrow area of the main outlet channel.