The City will replace the 100-year old cast iron watermain along Rowanwood Avenue, Thornwood Road, Chestnut Park and Roxborough Street with a newer, larger diameter watermain. This will improve the reliability of water supply to the neighbourhood.
Construction will take place from February 2025 to August 2026. The work will involve underground tunneling and open cut construction within the City right-of-way.
In February 2025, the City started work to replace the transmission watermain along Rowanwood Avenue, Thornwood Road, Chestnut Park and Roxborough Street. This included a temporary bypass of the watermain on Macpherson Avenue. In May 2025, work on Macpherson Avenue was paused due to unexpected underground conflicts that would have significantly expanded the work zone.
Originally, the watermain was relocated to support the work on Macpherson Avenue. The City is now preparing to restore the watermain work on Macpherson Avenue and return the watermain to its original location.
Work to assess options for the new reception shaft location is still underway and construction of the transmission watermain remains on hold. Additional notice will be provided before this work resumes.
Please see Construction Update Notice for full details.
During recent work at the Macpherson shaft site, the contractor discovered a steel beam and column structure. Further investigation revealed that the beams extend approximately 8 metres below ground. Removing these steel beams and columns to proceed with the construction of the tunnelling shaft would require additional trenching and a significant expansion of the work zone, resulting in further property impacts and a prolonged full road closure at the Macpherson Avenue and Yonge Street intersection.
To avoid these disruptions, City staff have advised against removing the steel beams and columns.
Currently, the City staff and the contractor are exploring the relocation of the Macpherson shaft site. This relocation would extend the overall project timeline, and a revised schedule will be developed accordingly. While the project team works through these technical adjustments, construction is on hold.
To minimize disruption to the community during this pause in work, the contractor will begin demobilizing from the site. This will include:
An update notice will be provided before work is to take place again.
The City is planning to replace the existing 900mm watermains on Rowanwood Avenue, Cluny Drive, Chestnut Park, Roxborough Street East, and Wrentham Place with larger 1200mm watermain to ensure sufficient water supply to residents.
Construction will involve both excavation of trenches (‘open cut’) and underground tunneling work for about 20 months.
Tunneling on Rowanwood Avenue will be carried out through two underground shafts (vertical tunnels). A tunnel boring machine (TBM) will excavate and construct the new watermain between the two shafts. One shaft at MacPherson Avenue, west of Yonge Street and the other shaft at Thornwood Road.
Open cut construction will take place on Thornwood Road at Chestnut Park and Rowanwood Avenue; Roxborough Street at Wrentham Place and Chestnut Park.
You may experience dust, noise and other inconveniences during construction. We appreciate your patience during this construction and will make efforts to reduce the impacts.
The route for the watermain was selected to reduce impacts as much as possible, however, there are areas where construction activities will be carried out in close proximity to businesses and residential properties.
Work will take place from 7 a.m. to 7 p.m., Monday to Friday, with work on weekends as required.
Sound and vibration monitors will be in place within the work zone to track and assess noise levels.
Each shaft work area will be surrounded by a temporary, 2.4 meter-high solid wood fencing. The fencing will ensure public safety around the shaft areas and reduce noise levels during construction.
From time-to-time, the water supply to properties will be shut-off to complete construction; The City’s contractor will provide notice at least 48-hours in advance. When water is shut off, it is recommended that you temporarily disconnect any water treatment systems (i.e. softeners or filters), water-cooled air conditioners or similar plumbing fixtures. In the event you did not receive advance notice, the City may have needed to use an emergency water shut off to complete work.
As part of the construction, 12 trees will be removed: Seven on Chestnut, four on Roxborough, and one on Thornwood.
The project team carefully designed the construction methods and watermain alignment to minimize tree loss, evaluating multiple alternative alignments during the design phase. Various engineering measures were explored and incorporated into the project to protect as many trees as possible, including trenchless technologies such as tunneling and directional drilling where feasible, adjusting utility placement, and refining excavation limits. These efforts allowed for the preservation of a significant number of trees; however, the loss of these 12 trees could not be avoided.
Trees within the construction zone that will not be removed are protected as per the City’s Tree Protection Policy.
The City has been working with businesses and property management representatives to accommodate delivery and loading activities during construction. If you have not yet discussed your delivery needs with the project team, please contact the staff person listed on this web page as soon as possible.
The City’s contractor must ensure safe and accessible walkways and entryways are maintained for everyone during construction. Any temporary access disruptions will be communicated as soon as possible. If you experience a disruption, have a specific access need or related accommodation request, contact the person listed on this web page.
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