Rain, conservation efforts help refill reservoir

By Lethbridge Herald on August 28, 2025.

Alejandra Pulido-Guzman
Lethbridge Herald

The City of Lethbridge has shared important information about water levels in the Oldman River Reservoir heading into fall. 

Mark Svenson, environmental manager with the City of Lethbridge said Wednesday that 2025 has been an interesting year for water supply. 

“We had a very low snowpack in the mountains, which resulted in very little runoff for the reservoirs this year, which meant the Oldman Reservoir was very low going into the season,” said Svenson. 

He said that, paired with the high demand from irrigation districts early in the season, kept the water levels below normal. 

“For most of the summer, the Oldman Reservoir has been at its lowest point since it was originally filled for this time of year, so it is substantially lower than normal,” said Svenson. 

That said, thanks to the substantial rain seen this summer, water levels have increased in the Oldman Reservoir. 

June 21 alone saw 58.8 millimetres fall in Lethbridge. That contributed to a month’s total of 96.6 millimetres – up from just 55.1 millimetres the previous June.

July followed suit with 103.5 millimetres of rain. That’s 150 per cent more than the average July rainfall, and 570 per cent more than the 15.4 millimetres that fell in July 2024. Cooler temperatures helped too, allowing the moisture to soak in.

“And speaking with Alberta Environment and protected areas, they are projecting by mid October the reservoir to be between 54 and 60 per cent full,” said Svenson. 

He said that even though this is still below normal, which is between 62 to 80 per cent full, it is substantially better than it was anticipated earlier in the season. 

And we may also have a better start to spring 2026, with winter forecasts calling for above average precipitation in southern Alberta.

“I want to thank our water users for continuing to look for ways to conserve water. We’ve been watching that, and they have managed to continue keep usage down from our baseline from 2023, which is great,” said Svenson. 

Many residents took advantage of the rebate program offered earlier this year for the purchase of rain barrels and low-flow toilets, which Svenson credited to the water conservation efforts.

“As of today (Uug.27), we have processed 391 rebates. The majority of those are for rain barrels, but about 60 low-flow toilets have also been put in, so that’s great,” said Svenson.