Water main break - Frequently Asked Questions (FAQ)

Local options were considered first. A pipe of this size is not generally used in oil and gas operations and is typically stocked by organizations that provide water to residents. This pipe could have been custom made locally, but it would have taken a lot of time. In the interest of time, the faster option was chosen to ship from San Diego to ensure that repairs were completed faster.

These pipes can last a long time, as much as 100 years in ideal conditions. 98% of Calgary’s feeder mains, which are critical pipes in our distribution system, are in good or very good condition. This is aligned with the target we have set for our system.

The most recent maintenance work happened in the spring of 2024, including replacement of air valves and the installation of an acoustic monitoring device. Routine field checks on valve chambers are also performed regularly.

Several test shutdowns were undertaken in the winter of 2023 and spring 2024 in preparation for a full condition assessment planned for December 2024.

98% of our water distribution system is rated as being in “good” or “very good” physical condition. This rating is due to The City’s ongoing condition assessment and maintenance programs, which help to identify and address potential problems.

We are unable to physically inspect all existing infrastructure every year, so physical condition is based on a combination of asset characteristics, physical observations, operational knowledge, and experience of known issues.

The Bearspaw South Feeder Main is the most critical feeder main in Calgary’s water system allowing for movement of water to the east and south parts of the city from the Bearspaw Water Treatment Plant.

Our water system is interconnected and what happens in one part of the system can impact another part. With the feeder main offline, none of the other pipes connected to the line could receive water.

Key facts about this feeder main:

• It's 11 kilometres long.
• It has the capacity to transfer more than 400 million litres of water.
• The diameter of this feeder main varies from 1.5 metres to nearly 2 metres.

Shouldice Fields received damage during the main break on June 5, and we are still assessing the extent.

Hotspots are additional locations of the water main pipe that required replacement. They were found as a result of analysis of the water main pipe in areas beyond the spot of the initial break of June 5, and have now been repaired. The hotspots were not leaks. They were sections of pipe that warranted immediate repair.

Residents cannot take water from Calgary rivers unless they have a valid permit from the Government of Alberta. Taking water from our rivers is regulated by the Province under the Alberta Water Act. The City of Calgary has the required permits to do so. We don't want residents slipping on rocks while carrying heavy containers, so we have established sites for easy pick up of non-potable river water for residential use (outdoor use) and for construction work. 

Only if the pool can be filled with potable water from a source that is not from The City's water supply.

At 8 a.m, June 15, The City of Calgary declared a State of Local Emergency as it deals with a water feeder main break impacting the City’s water supply.

Under the State of Local Emergency, The City has even more coordination of action. Declaring the State of Local Emergency is an indicator of the aggressive approach that was required to restore full water service for all customers as soon as possible. 

• The City is using non-potable water to irrigate our five golf course greens.
• City crews and contractors are using non-potable water collected from recent rainfall to protect trees, parks, flowers and sport fields.
• We've turned off all irrigation systems that use potable water. We are using non-potable water in areas where we need to protect new turf.
• Wading pools, spray parks, and outdoor pools will remain closed until the Outdoor Water Restrictions are eased so that final preparations that involve water use can be completed.

City-owned buildings and vehicles

• Facilities ceased watering plants and flowers, and irrigation of grass areas maintained for city-owned buildings.
• Decorative water features & fountains were turned off to conserve water.
• Annual flowers already planted were not watered while water-saving measures were in place.

Pools and arenas

• Indoor City-operated aquatic recreational amenities have reopened, including pools, hot tubs, steam rooms. Outdoor pools remain closed.

Operations and construction

• To avoid additional use of water to wash streets, Street sweeping has been postponed.
• The City worked with the Calgary construction industry to open three locations on the Bow River to provide non-potable water for construction work. 
  • This water is free of charge and will be the responsibility of the end user to ensure that water is appropriate for its intended application.
  • The City has the required permits from the Alberta Government to withdraw from the river.

More on how The City is conserving water. 

Now more than ever we recognize that events are an important way for Calgarians to connect with our community. Event organizers are generally approved to proceed as long as they adhere to water restrictions currently in place.

Indoor car washes are now able to operate normally.

Businesses are now able to resume normal indoor water use. Stage 4 Outdoor Water Restrictions remain in place.

Businesses are now able to resume normal indoor water use. Stage 4 Outdoor Water Restrictions remain in place.

Under Stage 4 Outdoor Water Restrictions, outdoor water use is banned. However, watering plants, shrubs and trees for commercial sale is allowed. We are asking all garden centers to be as efficient as possible with their water use. This includes checking all hoses for leaks and turning them off when not in use, using a watering can to hand water when possible and only giving plants the water they need. 

Yes. Community gardens are allowed to continue using water for their gardens during Stage 4 restrictions, according to the Water Utility Bylaw. However, we urge you to be as efficient as possible with their water use. This includes checking all hoses for leaks and turning them off when not in use, using a watering can to hand water when possible, and only giving plants the water they need to survive.

Consider putting a tote in your shower to collect clean, cold water while you’re waiting for it to heat up and reuse it to water your veggie garden. Don’t use water collected while shower in/bathing or other greywater to use on your edible plants.

According to the Water Utility bylaw, community gardens are allowed to continue using water for their gardens during Stage 4 Outdoor Water Restrictions, but we have been reaching out to them to urge them to be as efficient as possible with their water use. This includes checking all hoses for leaks and turning them off when not in use, using a watering can to hand water when possible and only giving plants the water they need to survive. 

At this stage in the growing season, veggie gardens need very little water to survive. Consider putting a tote in your shower to collect clean, cold water while you’re waiting for it to heat up and reuse it to water your veggie garden. Don't use water collected while showering/bathing or other grey water on your edible plants.

Yes, you can use grey water or water from rain barrels to water plants, shrubs, lawns and gardens. However, grey water and collected rainwater are not potable, which means you shouldn’t drink it. There also may be risks associated with using it on food crops.

If you choose to use rainwater or grey water on your food crops, follow these precautions:

• Use a drip irrigation system or hand water the plant roots with a watering can. This is called ‘base of plant’ watering and will help to prevent possible contamination of above-ground fruits and vegetables. 
• Wash all fruits and vegetables to remove as much contamination as possible. 
• See YardSmart - Rain barrels (calgary.ca) for more information on risks and precautions.

Whenever crews do a repair on a water main break, they need to flush the pipes to ensure water is safe to drink. While we take measures to reduce the amount of water used, flushing the pipe to meet drinking water regulations is a necessary process. The water used in this process is dechlorinated and returned to the river. At this time, we don’t have a mechanism for capturing and reusing this water.

If you know your neighbor, you may want to ensure they are aware of the outdoor water restrictions before reporting them to Bylaw.

Otherwise, please contact 311 so Bylaw Officers can follow-up to investigate the situation.

The City strives to take an education-first approach with citizens, it’s important that all Calgarians do their part. Therefore, there are penalties for violations.

The following exceptions, related to safety and core business needs, are allowed:

• Watering plants, shrubs and trees for commercial sale
• Washing outdoor surfaces to meet health and safety regulations at childcare facilities, restaurants, kennel and animal care facilities
• Washing of vehicles to follow health and safety regulations
• Washing windows manually by businesses that have a license to operate exterior window washing services
• Irrigation using non-City of Calgary water sources, such as rainwater collected in a rain barrel.

Although outdoor water restrictions should minimize water pressure problems, some customers may experience low water pressure at peak water demand times.

No. At this time of year, flows from the Elbow River are typically adequate to supply the high demands on the Glenmore Water Treatment Plant and keep the Glenmore Reservoir maintained.

Yes, a fire ban remains in effect for the City of Calgary. Learn more about the fire ban. 

However after consulting with the construction industry, we are working to accommodate specific lower-risk hot works activities for roofing (restrictions on this work apply and work using open flames are prohibited).

Hot works continue to be permitted in existing, occupied buildings where work is already underway and in existing, occupied buildings where work is needed to maintain the safety of the building and/or the health and safety of residents. Work such as welding and metal cutting that takes place in fabrication shops is permitted.

As of June 11, 2024 the following are now permitted:

All roof work, including new construction, done with Hot Air Welding and Cold Process roofing is permitted provided the following is in place:

• Fire watch in place for 60 minutes post-application, followed by an inspection of the area four (4) hours after completion of the work
• Increased fire extinguisher presence at worksite 

The following hot works are still prohibited:

• hot works with an open flame or with bitumen/tar kettles on new construction where fire separation and assemblies are not completed; and
• hot works with an open flame or with bitumen/tar kettles on existing, occupied buildings.

To learn more contact FireLegal@calgary.ca.

While The City strives to take an education-first approach with citizens, it’s important that all Calgarians do their part. Therefore, there are penalties for violations.

The fines are listed in the Water Utility Bylaw and range from $400 for a violation during Stage 1 to $3000 for a violation during Stage 4.

If you know your neighbour, you may want to ensure they are aware of the outdoor water restrictions before reporting them to Bylaw.

Otherwise, please contact 311 so bylaw officers can follow up to investigate the situation.

The feeder main pipe that failed is a pre-stressed concrete cylindrical pipe (PCCP). The pipe has a composite construction made up of a steel reinforcement cable sandwiched between layers of concrete.  

City engineers and external experts are working to fully understand the cause of the pipe failure, including the contributing factors that led to the premature deterioration of the pipe.

All pipes, regardless of pipe material, will deteriorate over time. In the case of a pre-stressed concrete cylindrical pipe (PCCP), both the concrete and the steel reinforcement can deteriorate and weaken over time. Some of the factors that can contribute to deterioration of a pipe include operating pressures, pressure transients (spikes in pressures), soil conditions, defects during the manufacturing process, physical damage during transportation or installation, poor installation practices, physical damage during excavation work adjacent to the pipe, and bearing loads applying excessive force on the pipe.

The pipe was operated well within its design pressure. The pressure in the pipe is continuously monitored, and the data confirmed that the pipe was operating at a pressure of approximately 70 psi at the time of the failure. This pressure is well within the pressure rating for this pipe. This pipe had a pressure rating of 150 psi, with a surge pressure of 210 psi.

Pressure stayed within a normal operating range for this pipe.  An analysis of pressure deviations has been completed as part of the ongoing review of the event.  This analysis supports the monitoring data.

The initial exterior visual inspection of one pipe segment that failed shows evidence of physical damage to the exterior of the pipe segment. It is unclear when this damage occurred.  This damage could have led to steel aspects of the pipe being exposed to the soil conditions, potentially leading to corrosion. This will be further investigated as part of the third-party review.

While it is impossible to provide a definitive answer, pipes are inspected immediately after installation. Any damage or deficiencies would be corrected before putting the pipe into service. A pipe can also be physically damaged when excavation works are happening in the vicinity of the pipe. A pipe strike would normally be investigated to confirm whether the pipe has been damaged.  Any damage would be repaired before backfilling the site.

A condition inspection is the best method we have to learning about our assets. An inspection using the latest pipe inspection technology would have likely detected “hot spots” along the length of the pipe.  This is how the five hot spots being repaired as part of this emergency response were found. The hot spots found are not pipe breaks; they are locations where advanced deterioration has occurred.

The inspection robot used to inspect the 4.3 km of pipe requires the pipe to be drained and empty of water. Alternatives are available where the inspection can be completed without draining the pipe; termed in-flow or in-stream condition assessment. 

An inspection plan was being executed prior to the pipe failure. A pipe inspection while in operation carries additional risks. Preliminary work was completed to replace air valves along the feeder main, valves were exercised (physically opening and closing the valves to confirm that they are working) and acoustic monitoring equipment was installed. This work was preparing for of an inspection scheduled for Fall/Winter 2024.  

The City has an annual inspection program for its pipe assets, including feeder mains. The logistics of inspecting over 5,000 km of pipe means that inspection data is supplemented with modeling of pipe condition. Inspection data are used to calibrate this model, which also incorporates factors of pipe material, pipe age, known condition, failure history, location, operating pressures, soil parameters and cathodic protection.

The model, along with an evaluation the assets hydraulic importance in the system, ease of repair, and by understanding the social, environmental, and financial consequences of potential failures, is used to guide inspection efforts and identify candidates for the pipe replacement program.  Pipe breaks are used to continually improve the modeling results. 

There are two types of acoustic monitoring available for this type of pipe. External acoustic monitors are discreet sensors mounted to the outside of the pipe. They pickup events within the pipe (possible wire breaks) but are low-resolution compared to the fiber optic monitoring. They can tell us if an event occurred near a sensor, but they cannot tell us which pipe section has experienced the event.

The second type of acoustic monitoring is fiber optic acoustic monitoring. Fibre optic cable is installed inside the pipe and is connected to a data acquisition system which can accurately identify the location of an event. Along with the baseline condition, data collected from the electromagnetic inspection can continuously monitor the condition of the pipeline so we can take appropriate action when the wire break count exceeds a threshold.

While the risk of a pipe break was deemed lower based on available data and modeling, The City did take action to reduce the impact of a failure. Investments in replacement air valves reduced risk factors to operations. The City has also invested in the reliability of the two water treatment plants and the broader pipe network to improve the capacity of the system to deliver water even when a failure occurs.

The 2011 and 2021 Water Long Range Plans also included future investments that will improve the redundancy of the system. An Emergency Response Plan for the Bearspaw South Feeder Main was prepared to quickly respond to a failure and maintain service while a repair was executed. This plan also included our critical parts inventory.