REGINA - The Water Security Agency has released its preliminary spring runoff outlook for 2023, and it shows near-normal runoff is expected for the southeast.
The report is in advance of its initial Spring Runoff Report for March 2023, and shows a range of snowmelt conditions across the province based on conditions on Feb. 1.
Both Rafferty Reservoir and Grant Devine Lake are below their prescribed Feb. 1 drawdown elevations. With drier than normal conditions at freeze-up in 2022 and what is estimated to be a near to slightly above normal snow pack, the snow-melt runoff response is expected to be near normal above the three reservoirs and above normal in the area below the reservoirs to Sherwood crossing.
Additional drawdown of the reservoirs is not expected, and it is anticipated that reservoir releases during the spring runoff period will be limited to amounts required to meet international apportionment obligations. At this time, Boundary Dam Reservoir and Grant Devine Lake are expected to fill during spring runoff. Any excess water from Boundary will be diverted to Rafferty.
At this time, Rafferty Reservoir is not expected to fill from snow-melt inflows in 2023.
Detailed forecasts for the Souris River Basin are developed on or near the first and 15th of each month, beginning in February, up until the snow-melt runoff event. These forecasts can be found on wsask.ca.
Other findings in the report were:
- Most of southern Saskatchewan had below normal snowmelt runoff potential. Much of the southern areas experienced very dry conditions through the summer and into the fall, according to the report.
- Central areas, with above normal snowpack, can expect an above normal snowmelt response. The snowpack is generally above to well above normal to date but flooding is not expected despite the predicted above normal runoff.
- The far north, encompassing the areas of Uranium City, Stony Rapids and Cluff Lake are anticipated to experience a near normal runoff event.
According to the Water Security Agency the runoff potential is determined based on several factors including conditions at freeze-up, the snowfall received to date and potential expected further precipitation between now and spring melt.
The report also raised some concerns about surface water supply issues being likely in southwestern Saskatchewan this year. The report states that with depleted subsoil moisture, a slow melt will likely result in the bulk of the snowpack recharging the soil column, and that a rapid melt is likely needed to result in improvement to surface water supplies. The current snowpack is not sufficient to satisfy both, their report states. They do note the spring runoff outlook could change.
