The Water Security Agency is preparing for an influx of water expected to flow into Lake Diefenbaker just northwest of Moose Jaw, as a low-pressure rain system is forecasted to hit southern Alberta.  

The system is expected to bring 50 millimetres to southern Alberta, and 100 mm to the Alberta foothills beginning on Wednesday.  

The agency says the large quantities of rain from Alberta will affect one or more of the subbasins contributing to the South and North Saskatchewan rivers, which will cause Lake Diefenbaker’s water level to rise drastically.  

“We’re certainly going to see some inflows coming into Saskatchewan from Alberta rise significantly so we don’t know how much right now, but we’re looking at that as it happens and try to plan and account for it going forward,” says Water Security Agency Spokesperson Patrick Boyle.  

In preparation, the agency will begin increasing outflows in stages this week at the Gardiner Dam. They began on Monday increasing the outflows to 90 to 100 cubic metres per second, and with more expected by the end of the week, until the capacity of the Coteau Creek Hydroelectric Station is 400 cubic metres per second. 

“We’re seeing a general idea of how much is going to come there, so we’re accounting for that on the outflows and releasing water, and it’s coming out on the other side of the lake, it’s going to be downstream of Saskatoon,” adds Boyle.  

In addition to the Alberta rain system, Boyle notes the agency is also releasing water to account for the influx of mountain run-off that is expected.  

“It was delayed this year. Temperatures were pretty cold in the mountains this year and the snowpack was well above normal.” 

Boyle reminds residents living along the South Saskatchewan River into the lake, that with the expected water level increase, flooding may occur.  

“One of the biggest things there for residents is any infrastructure that you do have, right now the lake level in the area is fairly low so irrigators and pump intakes, they’re going to be farther in the water and you’ll have to move those back as that water comes in.” 

The agency adds that they have been in contact with area residents below and above the lake to advise them of higher flows coming in both sides.  

While widespread flooding in Saskatchewan is not predicted at this time, citizens facing flooding issues are encouraged to look into WSA's Emergency Flood Damage Reduction Program (EFDRP).  

EFDRP provides assistance to implement emergency flood protection measures for communities, rural municipalities, businesses, non-profit organizations, individuals with rural yard sites, country residences and cottages to prevent damage from imminent risk of flooding. Details of the program can be found here. 

WSA will continue to monitor conditions and provide updates as the situation develops.