Calgary races to complete new repairs to feeder main

Key Takeaways:

• The City has identified additional urgent repairs for the Bearspaw South Feeder Main, informed by recent PipeDiver device results and ongoing acoustic monitoring.
• These repairs must be completed by the end of September to prevent potential water system failures.
• To facilitate the repairs, the South Bearspaw Feeder Main will be shut down from August 26 to the end of September, necessitating Stage 4 Outdoor Water Restrictions and a request for residents and businesses to significantly reduce non-essential water use.
• Officials are currently developing a rehabilitation plan, with reinforced concrete encasement being the preferred method.
• The majority of the repair work will occur along 33 Avenue N.W., with potential additional repairs on Parkdale Boulevard and 16 Avenue N.W.

The Whole Story:

Calgary’s water woes have not yet dried up.

The city has announced that, based on new information, additional urgent repairs are needed to the Bearspaw South Feeder Main.

The conclusion is based on analysis of the recent results from the city’s PipeDiver device, combined with previous testing and ongoing acoustic monitoring. Officials noted that while this is not an emergency situation like the city experienced in June, the new data has uncovered additional points in the pipe where urgent repair work is needed by the end of September.

“This news is not what any of us wanted to hear,” said Mayor Jyoti Gondek. “However, I am grateful that we have the PipeDiver results. That important information is allowing us to immediately act to protect our water system against potential breaks. To everyone in the Calgary region, particularly residents and businesses in Bowness and Montgomery, I understand how much this impacts your lives. You have my word that we will continue to do everything we can to improve the stability and security of water in our city.”

Timing is crucial for managing Calgary’s water supply through the winter. Calgary sources its water from the Bow and Elbow Rivers. The Bearspaw Water Treatment Plant draws water from the Bow River, while the Glenmore Water Treatment Plant sources from the Elbow River. During spring and summer, river flows are higher due to rainfall and snowmelt in the mountains. In late fall and winter, the city relies on the Glenmore Reservoir as its water “bank,” drawing it down as flows on the Elbow River decrease. The repairs need to be completed while the flow is still high enough to refill the Reservoir for winter.

Repair work and timing

To facilitate these urgent repairs, crews will need to shut down the South Bearspaw Feeder Main and stop the flow of water through it between August 26 and the end of September.

During this time, the city will return to Stage 4 Outdoor Water Restrictions and officials will also be asking Calgarians and businesses to limit their non-essential indoor water use to reduce the strain on rivers and water treatment plants while work is underway.

Residents will be asked to take three specific actions: taking three-minute showers, skipping flushes where possible, and only running full loads of laundry and dishes. Businesses will be asked to aim to reduce indoor water use by 25%. No businesses will be asked to close unless absolutely necessary. The City of Calgary will also be reducing its non-essential water use.

“We understand that water restrictions play a major role in the day-to-day life of Calgarians, and we want to thank you for your continued support as we rehabilitate the Bearspaw South Feeder Main together,” said Michael Thompson, general manager, infrastructure services. “These urgent repairs are required to proactively support the stability of our water system. We are committed to getting the required repairs completed to keep water flowing safely to you.”

Next steps

The majority of this work will take place along a section of 33 Avenue N.W. There will also likely be a repair required on Parkdale Boulevard, and crews may also perform some additional repairs on 16 Avenue N.W. The precise locations and extent of these repairs will be communicated in the coming weeks as officials learn more information. The city will communicate directly with impacted residents and businesses in the area as construction plans evolve.

Officials are currently developing a rehabilitation plan, with reinforced concrete encasement being the preferred method. This involves exposing the pipe through excavation, constructing an exterior reinforcing steel cage, pouring concrete and backfilling the excavation. Although this method does not involve removing pipe segments, the pipe must be taken out of service due to the water pressure and to ensure worker safety. The city also has contingency plans in place should it encounter additional issues, and officials say they are prepared to respond rapidly.

For now, Calgary remains in Stage 1 Outdoor Water Restrictions until work begins the week of August 26. The city will have teams working 24 hours a day, seven days a week to restore water service to Calgarians as safely and quickly as possible.

The crisis began with a major break in a feeder main on June 5 which is one of Calgary’s most important water supply lines. This break caused extensive flooding and disrupted the water supply to approximately 1.2 million residents.