Update July 16: Critical water main break affecting city-wide water usage

We have reached an important milestone in our efforts to reduce Outdoor Water Restrictions. Until recently, water flow through the pipe was at about 55% of its maximum capacity, limiting our supply. To address this, we needed to increase water flow through the pipe, which also increases pressure and can potentially damage the pipe walls.
After extensive planning and careful analysis, we activated an additional pump at the Bearspaw Water Treatment Plant yesterday. This allowed us to start increasing the water flow through the pipe while managing the pressure to avoid damage. We are pleased to report that the process has been successful so far, with water flow increasing steadily and no issues detected in the pipe.
This progress is encouraging as we aim to stabilize the pipe at 70% water flow and if things continue smoothly, we could move to Stage 2 Outdoor Water Restrictions by Thursday, July 18.
Bearspaw Water Main
Proceeding cautiously and preparing for setbacks
We continue to proceed with caution as we monitor the pipe closely for any further issues. While we fixed five "hot spots" requiring emergency repair, we know there are other areas of structural weakness that need medium-to-long-term solutions. Our priority was to fix the hot spots first as they were critical in being able to restore normal indoor water use and allow as much outdoor water use as possible.
In the past few weeks, we’ve gathered valuable information about the pipe's condition, allowing us to make some projections about how it might respond to increased pressure. We've been using acoustic monitoring to detect snaps in the wires that coil around each pipe segment, which indicate that the pipe is under stress.
Yesterday morning, our acoustic monitoring detected one additional snap, bringing the total to four. However, this was before the new pump was turned on. We have not detected any snaps since the pump was turned on. If this changes, it could affect our ability to move to Stage 2 Outdoor Water Restrictions and beyond.
Water use and heat
Yesterday our water use was 558 million liters, which is an increase from Sunday but still within manageable limits. With more heat in the forecast, we expect that water use will rise alongside temperatures.
Daily Demand Graphic JUL16
Although our goal is to reduce Outdoor Water Restrictions, for now we remain in Stage 3. This means watering by hand with a can or other container is required, except in specific circumstances like watering new grass or sod. If you know someone who needs help watering by hand, please consider becoming a Water Angel and offer your help.
The best times to water are early morning or late at night to minimize evaporation and reap the biggest benefits for your plants. If we can move to Stage 2 Outdoor Water Restrictions, it will allow activities such as using a sprinkler for up to 1 hour per week and using hoses with spray nozzles.
Irrigators
We understand that Outdoor Water Restrictions have been challenging for certain businesses like landscape and irrigation companies. We are sympathetic to these concerns and have been working closely with the Irrigation Association to provide support within the Stage 3 Outdoor Water Restrictions that are in place.
Our Water Utility Bylaw allows certain construction activities at Stage 3, and we have now expanded this to include maintenance of irrigation systems. This means irrigation companies can run water through the pipes of in-ground sprinkling systems if they are fixing irrigation lines or checking to see if they are working properly. However, after maintenance is completed, property owners must still follow the current Outdoor Water Restrictions in place for irrigation systems.
While we know this doesn't fully address the industry's concerns, we hope it is a step in the right direction and helps them expand the services they are currently able to provide. More information is available in the Frequently Asked Questions section on calgary.ca/restrictions.
Next steps and timing
If the pipe and our system remain stable over the next two days, we will be on track to move to Stage 2 Outdoor Water Restrictions by Thursday, July 18. However, if we detect any stress or new damage before then, we might have to stop. We will continue to monitor closely and keep you updated on our progress.
You can find more details on our progress and status, what is allowed during different stages of Outdoor Water Restrictions and lots of other information at calgary.ca/restrictions.