South Sask. River still Parched - River Report #2 May 8
The South Saskatchewan River on Wednesday afternoon. Stream flows on the river at Medicine Hat are running in the red zone, falling below the 42.5 cubic metre a second threshold. (Photo Alex McCuaig)
The South Saskatchewan River is still waiting to receive its spring diet of precipitation and mountain runoff as the second week of May gets underway.
It might get at least a little of both in the next seven days as warmer temperatures at higher elevations and rain is expected right across southern Alberta starting early next week.
Stream flows have been running below 50 cubic metres a second on the South Saskatchewan over the past week with the month starting with levels falling below the instream objective (IO) of 42.5.
Thursday morning saw the river once again dip below that threshold.
Bow River irrigation reservoirs at Lake Newell and McGregor are nearing capacity levels. However, stream flows at the fork of the Bow River are running in the red zone, falling under the water conservation objective.
The Oldman River is also failing to reach both the instream and water conservation objectives (WCO) at the forks, recording a stream flow of 17 cubic metres a second. The IO is currently set at 20 cubic metres with the WCO set at 56.
Releases from the Oldman dam have more than quadrupled since April 27, going from 11 to nearly 46 cubic metres a second. The Oldman Reservoir is currently holding a little less than 60 per cent of its capacity.
Reservoirs fed by tributaries from the Cypress Hills are either at or over capacity with Sauder (Rattlesnake) reservoir nearing 99 per cent full. Murray Lake is an exception running at near 75 per cent capacity.
Alberta Environment’s mountain runoff forecast is currently predicting much below to below average levels for the Eastern Slopes running into the Bow and Oldman river basins.
Soil moisture levels, however, continue to be moderately high from Taber to the Special Areas and east to Saskatchewan border. Areas in the far southwestern corner of Alberta and directly surrounding Medicine Hat city limits are reporting moderately low moisture levels with the driest areas running along the US border near Warner County to Pincher Creek.
Environment Canada’s May temperature outlook is predicting warmer than normal temperatures across the southern prairies.
A weather system is anticipated to bring rain to much of southern Alberta starting Sunday night through to May 14.