River Report #4 – Conditions Ripe for Excellent Growing Season
The South Saskatchewan River at the confluence with Seven Persons, Ross creeks on Thursday morning. (Photo Alex McCuaig)
The table is set for a solid growing season as good soil moisture is combining with seasonal temperatures and modest precipitation allowing farmers to get an exception start across southern Alberta.
With seeding heading for completion across the region by the end of May, forecast hot temperatures in the coming week should provide good conditions for an equally early emergence of crops.
While conditions on southern Alberta rivers haven’t faced early season pressure from irrigated crops, things aren’t fairing great.
But the region’s traditionally wettest month, June, has yet to reveal what Mother Nature has in store for this part of the province.
Rain will be required to buoy river levels as the mountain snowpack runoff has peaked and is well into its downward seasonal trend.
The South Saskatchewan River at Medicine Hat has yet to see triple digit streamflow numbers since early April despite a sharp increase in calculated natural flow figures, an indication upstream reservoirs are continuing to be filled.
Streamflows in the past seven days in the Hat peaked at 87 cubic metres a second on May 20th and have steadily drop the past two days to 69 cubic metres Thursday morning.
Water conservation objects (WCO) on the South Saskatchewan River continue to not be met over the last two weeks with river levels also skirting above and below the instream objective (IO) of 42.5 cubic metres a second since the beginning of May.
An extended failure to reach either objective could impact water licences.
An increase from streamflows from the Bow River should help improve the situation but may only serve to match the decreases of discharges from the Oldman River into the South Saskatchewan.
(Graphic courtesy of Alberta Environment)
Lethbridge is also seeing similar streamflow challenges on the Oldman River, continuing to not meet WCO levels while dancing just above its IO of 20 cubic metres a second. The river at Lethbridge is running at 22 cubic metres a second Thursday morning, hitting a seven-day high of 34 cubic metres a second on May 18.
The Oldman Reservoir is also reporting below normal levels, currently sitting at 64 per cent capacity.
St. Mary River Irrigation District (SMIRD) reservoirs collectively are rated at normal levels. The district’s namesake and largest reservoir is sitting at 81 per cent capacity and is rated above normal for this time of year.
Weather forecasts for the next week are predicting hot temperatures descending on southern Alberta, peaking in the low 30s from Pincher Creek to Medicine Hat by mid-next week.