Provincial Forecast

October 2025 Water Supply Conditions and Outlook Report

November 27, 2025

Please see the November 27, 2025 update below:

With the seasonal closure of many of the streamflow gauging stations used in the development of this product and freeze-up underway, this will be the final 10-Day Saskatchewan River Basin Forecast for 2025. The production of this product will resume in 2026 once the necessary data becomes available. This will occur following the breakup of the ice cover on the channels, which typically occurs in late April on the South Saskatchewan River and early May on the North Saskatchewan River.

At this time, we expect that winter flows and reservoir outflows throughout the system will be approximately normal. The Water Security Agency will continue to keep stakeholders which have the potential of being impacted by changing flows informed through direct communication during the winter period if significant changes to flows or levels are expected.

South Saskatchewan River Basin:

• Inflows to Lake Diefenbaker are expected to stay steady between 95-105 m³/s. The Inflows into Lake Diefenbaker remain close to upper quartile range for this time of year but are slowly receding. With freeze-up processes underway, inflows to Lake Diefenbaker are expected to drop closer to median levels next week.
• In preparation for the onset of freeze-up conditions, the outflow from Gardiner Dam was increased to 220 m³/s on Tuesday November 25. The operation plan is to continue releasing in this range.
• The reservoir is at 554.90 m. This level is near the median for this time of year. Based on the forecasted inflows and the increased outflows, the reservoir elevation is expected to decrease by 0.23 m over the next 10 days.

North Saskatchewan River Basin:

• The water level readings near the Alberta border and at Prince Albert indicate the river channel is starting to freeze over.
• Flows on the North Saskatchewan River at Prince Albert have dropped below median levels for this time of year and are expected to continue to drop over the weekend and stay low into next week. Once the river is fully frozen, flows are expected to increase back near median.

Saskatchewan River Basin:

• Despite increased releases from Lake Diefenbaker, inflows to Codette Reservoir are expected to decline sharply this weekend and could approach very low levels depending on the progression of the freeze-up.

• Cumberland Lake water levels remain lower than normal for this time of year and are currently below the lower quartile range. Inflows are expected to decline over the next week as freeze-up progresses. After freeze-up, Cumberland Lake water levels are expected to start rising due to backwater effects from ice formation in the river channel and increased inflows driven by higher releases from lake Diefenbaker.