A clarifier at the Lethbridge Water Treatment Plant. (Image Credit: Lethbridge News Now)

By David Opinko

UV disinfection upgrades underway at Lethbridge Water Treatment Plant

Feb 11, 2026 | 2:53 PM

The City of Lethbridge is continuing to make improvements to its Water Treatment Plant.

They say upgrading its ultraviolet (UV) disinfection system is an essential step that keeps the community’s drinking water clean and safe.

“The work may be happening behind the scenes, but the benefits are anything but invisible,” reads a news release from the City. “They’re long-lasting, cost-saving and designed with residents in mind.”

According to the City, it was an early adopter of UV disinfection when it was installed in 2003.

Water and Wastewater Engineer Ted Larson says, “We were pioneers at the time, and now we’re bringing that same forward-thinking approach into the future.”

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Technology has continued to evolve over the last two decades with smarter, safer and more efficient systems.

Engineers can pinpoint the exact UV dose needed to disinfect water, which allows municipalities to use less energy.

Currently, the aging system runs at full power around the clock, even when demand dips.

“The new reactors change that completely,” the City says. “They automatically adjust their brightness based on how much water is flowing through the plant. When demand is low, the lamps dim. When demand rises, they brighten. It’s simple, smart and efficient.”

The City says the upgraded UV system will use 78 per cent less electricity, which it estimates will save roughly $120,000 every year.

It will also increase the system’s capacity and support plans to boost water treatment from 150 million litres per day to 180 million.

Other improvements include clarifiers, pumps, chlorine dosing and filters. Design work for those next steps is already underway.

The upgraded UV reactors have already been purchased, and they should be fully installed by the end of this year.

READ MORE: $9.2 million grant to move Lethbridge Water Treatment Plant upgrades forward