Historical Lake Diefenbaker Inflows

Inflows to Lake Diefenbaker are driven by spring runoff from the prairies, mountains and spring and summer rainfall. Mountain runoff generates most of the inflow to the reservoir. In 2023, the mountain runoff was less than usual, and there was no significant spring or summer rainfall events. As a result, the inflows were only 26 per cent of normal, leading to lower water levels than usual throughout the summer. The current water level on the reservoir is the second lowest in 33 years, with 2001 being the lowest.