Airdrie’s upcoming tie into Calgary’s wastewater system is already part of the more than decade-long expansion of the Bonnybrook wastewater treatment plant, according to the City.

On July 30, the Government of Alberta announced $50 million to help support the construction of a seven-kilometre wastewater pipeline for Airdrie that connects to the City of Calgary’s existing wastewater infrastructure.  

The total cost of the project is $114 million.

According to Alberta Minister of Transportation and Economic Corridors, Devin Dreeshen, the expansion and connection will help support an additional 45,000 housing units and several commercial developments in the area. According to a provincial release, Airdrie recently annexed 10,000 acres of land on its east side.

“Airdrie is one of the fastest-growing municipalities in Alberta, and needs upgraded infrastructure to meet the demand for new, serviced, subdivisions,” Dreeshen said in the media release.

According to the City of Calgary, Airdrie is part of its north wastewater catchment area, serviced by the Bonnybrook wastewater treatment plant.

When asked if the potential addition of 45,000 housing units and the commercial areas would accelerate the need for further expansion of the Bonnybrook plant, the City said the current upgrade is incorporating growth for both Calgary and regional neighbours.

“The City of Calgary works closely with our regional customers on long range infrastructure planning since our master servicing agreements are in place for 20 years,” an email response to questions read.

“The City meets regularly with the City of Airdrie, and considers their growth needs in our infrastructure planning, including for treatment plants.”

The $1 billion Bonnybrook wastewater treatment facility expansion first began in 2016. The upgrades, which the City of Calgary said would be complete and operational by 2026, will bring the plant capacity up from servicing 950,000 citizens to 1.4 million.

Calgary also operates the Fish Creek and Pine Creek wastewater treatment plants.

Regional customers are paying for their share of water upgrades: City

Calgary’s water and wastewater system operates on a mostly user-funded system for both the operation and any capital upgrades.

Still, Calgary city council approved borrowing $1 billion for new water utility projects, and includes two new water feeder mains and a proposed new water treatment plant.

The $1 billon cost for Bonnybrook upgrades alone, to accommodate regional growth demands, aren’t all borne by Calgary ratepayers, however. (The Bonnybrook expansion costs are separate from the borrowing endorsed by city council.)

“Regional customers pay rates that cover all costs of the service they receive, including infrastructure,” the City said.

“The City ensures regional cost allocation is current through the Cost-of-Service Study (COSS) conducted every four years.”

The City said that the costs for an upgraded wastewater plant are financed by off-site levy growth within Calgary and by regional rates regulated by the Alberta Utilities Commission for regional customers. That’s based on total water used and wastewater treated, the city said.

The province said that the new pipeline project allows Airdrie to continue growing sustainably, while leveraging regional infrastructure assets, instead of building a new water treatment facility of its own.

Design work on the pipeline is expected later this year, with construction to begin next year and completion anticipated for 2027.

Calgary’s Bonnybrook water treatment plant was built in the 1930s.