The City of Calgary has responded to an unintentional wastewater leak into the Bow River, with no impact on Airdrie’s water supply.
Airdrie receives its water from Calgary, where officials have confirmed that drinking water quality has not been affected by the leak. Calgary’s drinking water, drawn from sources upstream of the leak, remains safe to drink, and Alberta Health Services says, based on available data to date, the risk to the public as a result of this event is extremely low.
There are no boil water advisories or recreational use restrictions for the Bow River at this time. Calgary’s monitoring data indicates that the leak was contained, and water quality testing continues.
On Friday, March 28, crews identified a leak on the east bank of the river, across from the Bonnybrook Wastewater Treatment Plant by the Ogden Road bridge.
Upon discovering the leak, the City of Calgary said that it immediately reached out to Alberta Health Services, Alberta Environment and Protected Areas, and communities downstream.
According to officials, monitoring indicates that this action has contained the issue, but ongoing testing and water quality assessments are continuing.
City crews first noticed a potential issue on March 19, when monitoring systems at the Bonnybrook Plant identified that wastewater levels flowing to the plant were lower than normal.
Crews investigated potential causes, including checking for seasonal variations and plant issues, but no abnormalities were found. As wastewater levels continued to drop, crews expanded their search to external factors, including:
-
Checking with regional customers to determine if less material was being sent to the plant.
-
Monitoring changes across Calgary’s 5,000-kilometre wastewater system.
-
Reviewing data from lift stations and 311 reports for any indications of leaks.
On Thursday, March 27, crews conducted a visual inspection of the riverbank and took water samples for testing. No visible signs of a leak were detected at that time. However, on Friday morning, test results showed elevated E. coli levels in the river near Bonnybrook.
A second inspection was conducted at 11 a.m. Friday revealed a visible leak. There are three pipes in that location that carry untreated wastewater under the river to the Bonnybrook Plant. Crews immediately began investigating which of these pipes was the source of the leak.
By 2:30 p.m. Friday, the faulty pipe was identified and shut down. Wastewater was rerouted to the two remaining functioning pipes, allowing service to continue. Since that time, wastewater flows into Bonnybrook Wastewater Treatment Plant have returned close to normal.
"This incident highlights the importance of having built-in system redundancies. Within hours of getting the test results, we shut down the impacted pipe," says Doug Morgan, General Manager of Operational Services.
"The three wastewater pipes leading to the Bonnybrook plant are designed to support each other in cases like this, ensuring continued service to Calgarians."
The City is currently conducting a full assessment of the incident. Calgary, AHS, and Alberta Environment and Protected Areas (EPA) continue to monitor the situation, including ongoing sampling and testing to ensure water quality remains safe.
Residents and their pets, should avoid contact with the affected area. Fish from the Bow River should be cooked before being consumed.
"We know when it comes to infrastructure, Calgarians want to know about incidents as soon as we know," said Mayor Jyoti Gondek.
"When I learned of this leak last night, I immediately called a briefing and told the team we needed to share all details with the public at our first opportunity."
"This incident highlights the importance of strong back-up plans. Because of those plans, Calgarians can have confidence in the systems they depend on daily."
Downstream communities, including Heritage Pointe and the Siksika Nation, have been notified and offered support with water quality testing.
Sign up to get the latest local news headlines delivered directly to your inbox every afternoon.
Send your news tips, story ideas, pictures, and videos to news@discoverairdrie.com. You can also message and follow us on Twitter: @AIR1061FM.
DiscoverAirdrie encourages you to get your news directly from your trusted source by bookmarking this page and downloading the DiscoverAirdrie app.