TransCanada Sanitary Trunk
Project status – June 2025
Construction work continues on a section of Forzani Way which includes work on existing manholes and preparation for microtunnelling work which is required to install the sanitary trunk underground. We have successfully moved in some equipment including a crane and excavator, conducted surveying, marked existing utilities and began building the microtunnelling shaft. For more information on what microtunnelling is, scroll down the page. We are now preparing for microtunnelling work on various sections along the trunk’s route.
Thanks to those who attended our open house on May 26!
A shaft, which is a vertical access point for microtunnelling equipment, was installed on Forzani Way. From here, equipment will be lowered down the shaft in preparation for the microtunnelling process.
| Where are crews currently working | What’s the timeline for the current work | What crews are working on | Traffic impacts |
|---|---|---|---|
| Forzani Way N.W. | April 28 – May 30 | Construction fencing, tree protection fencing, installing sediment logs (which look like sandbags) to prevent soil erosion, hydrovacing to locate existing utilities, crane set-up, building a temporary residential access road, shaft construction near the Forzani Way cul-de-sac, microtunnelling equipment set up. | None |
The west side of Calgary along with the Town of Cochrane are currently serviced by the Valley Ridge Sanitary trunk, which transports sewage produced by homes and businesses. As a result of population growth over the last several years, the trunk is nearing its capacity. For this reason, along with the projected population growth in the future, another sanitary trunk is needed which will be The TransCanada Sanitary Trunk (TCST).
This new 8.5 kilometre long sanitary trunk will transport sewage from regional customers such as the Town of Cochrane and other developments along the TransCanada Highway. The infrastructure plans were developed with the community in mind and utilizes methods to reduce the environmental impact during construction. Of the approximate 8.5 kilometres, about 7.3 kilometres will use the process of microtunnelling while only 1.2 kilometres will be open trench construction. Microtunnelling is a method of installing utilities underground – essentially an underground tunnel – which minimizes environmental, health, and traffic impacts. (See figure 1 for more information).
Project benefits
- This project is essential to meet sewage demands in the west part of Calgary given recent population growth and provides adequate capacity for future residential and commercial development to take place.
- Specific sections of this project work will be completed by microtunnelling, which reduces construction impacts on traffic, parks and green space. This work will primarily near the community of Valley Ridge along with another large section east of Stoney Trail to Sarcee Trail N.W.
- Reduces odours in the community of Valley Ridge.
Project timeline
- Detailed Design – Complete.
- Construction - Began April 2025 to Q4 2026.
- Landscaping – Scheduled to be complete by Q4 2027.
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Connect with the project team
For more information, please contact the project team at:
TransCanadaSanitaryTrunk@calgary.ca.
Project maps
Construction route access in Valley Ridge
UPDATED MAY, 2025. These maps show the proposed routes construction trucks will use during the TransCanada Sanitary Trunk project. The time duration of these routes is still being determined and will be updated on our website.
Construction route access in the Bowdale area
UPDATED MAY, 2025. These maps show the proposed routes construction trucks will use during the TransCanada Sanitary Trunk project. The time duration of these routes is still being determined and will be updated on our website.
Construction route access along the TransCanada highway
NEW: added May, 2025. These maps show the proposed routes construction trucks will use during the TransCanada Sanitary Trunk project. The time duration of these routes is still being determined and will be updated on our website.
Construction mitigations
Keeping the sound barrier intact
We will be using microtunnelling to install portions of the sanitary trunk that allows us to keep the sound barrier on 16 Avenue N.W. in place during construction. This is an area just west of Stoney Trail where the tunnelling passes under the sound barrier. Click to enlarge.
Tree protection
Trees just north of the TransCanada Highway and west of Stoney Trail will be protected by the process of microtunnelling as the sanitary trunk will be installed underground without disturbing the surface.
Microtunnelling
Microtunnelling is a method of installing utilities underground – by essentially building an underground tunnel – which minimizes environmental, health and traffic impacts. For this project, more than 85 per cent of the sanitary pipe/trunk installation will be through microtunnelling.
Step 1 - Build the shaft
A hole is dug at the site of where the shaft will be built. The shaft is a vertical excavation that leads down to where the underground tunnel begins at one end. It also houses the equipment used to dig horizontally to the next shaft.
Step 2 - Set up equipment
Equipment such as the microtunnel boring machine, used to dig out the soil and other material to create the tunnel, and the pipe jacking machine, which will push the sanitary trunk piping through the tunnel, are put down the shaft via a crane where they're set up.
Step 3 - Install the sanitary trunk piping
A boring machine digs horizontally and the pipe jacking machine pushes the sanitary trunk pipe through the tunnel, essentially installing the trunk underground. The process is repeated with alternate sections of pipe until the line is complete.
Frequently asked questions (FAQ)
What size will the trunk be?
The trunk will have both 1350 mm and 1500 mm pipe sizes.
Why is this new sanitary trunk needed?
The TransCanada Sanitary Trunk (TCST) is needed because the current trunk that serves the west part of Calgary along with the town of Cochrane is nearing capacity. This project is essential to meet sewage demands in the west part of Calgary given recent population growth and provides adequate capacity for future residential and commercial development to take place.
Will the trunk be built all at once or in sections and if so, what would the construction timeline be for each section?
We are in the process of hiring a contractor for the project at which point they will develop a construction plan that will detail section sequencing along with timelines. We will communicate this on our website once we learn these details.
When will construction begin and how long will it take?
Construction is planned to begin in Spring 2025 and will last for approximately two to three years.
How will I know about construction and its impacts in my area?
We will notify residents through mailing a construction notice and we will also update our website regularly.
Will Bowdale Crescent NW be closed during construction?
No, we will be widening the Bowdale Crescent ramp to allow vehicles to turn and get access to the Community.
Will trees be removed as part of the project?
Some trees will be removed on Forzani Way that are located on the Utility Right of Way. The project will pay for the compensation of the trees that require removal and The City’s Urban Forestry will replant the trees in an area of need to maintain our tree canopy. We will also remove Caragana plants, which are not a native species and are invasive. Any grass that is disturbed will be re-seeded once construction is complete in this area.
Is there other construction in the area unrelated to the TransCanada Sanitary trunk that will result in impacts such as construction truck traffic?
Yes. There are two other projects in the area that are not City infrastructure projects that are resulting in construction impacts. These are: Osprey Hill Developments (south of the TransCanada and just east of Stoney Trail) and Greenwhich and Upper Greenwhich (north of the TransCanada Highway and just east of Stoney Trail). For more information, please contact the developer on their project websites: Osprey Hills: www.Experienceospreyhill.com, Greenwhich: www.greenwhichcalgary.com, Upper Greenwhich: www.uppergreenwhich.com