Caisson drilling has been well underway and will continue with upcoming extended hours around the Davenport Diamond Guideway project. It’s needed work, but it can be taxing on the local community. Here’s what’s happening, why it’s needed and what noise mitigating measures are being taken so neighbours can sleep at night.
Those living around the Davenport Diamond Guideway project have to sleep at night.
Amid extended hours on this important project, experts are working hard to make sure those neighbours aren’t left tossing and turning– though patience will be needed to get the heavy effort done.
We break down the why, as well as what’s being done to keep the commotion down as much as possible.
Delivering a major infrastructure project in a community is always challenging. Metrolinx has worked closely with contractor Graham Commuter Rail Solutions to plan upcoming extended hours of work, and mitigation measures, to minimize disruptions to neighbouring communities.
The new guideway – between approximately Bloor Street and north of Davenport Road – will replace the rail crossing near Dupont Street and span over the Canadian Pacific (CP) tracks, enabling service improvements without conflicts with freight trains. This new infrastructure will help support two-way, all-day, more frequent train service on core segments of the Barrie GO line and improve safety as well as connections in the community.
Caisson drilling – you can find out more about it further down in this article – has been underway since last month. Until now, most of the work has been carried out between the hours of 7 a.m. and 11 p.m., with the occasional late night or overnight shift.
Starting Jan. 30, the drilling will move to an extended work hours schedule. Crews will start work at 7 a.m. and continue overnight until 3 a.m. the following day, six days a week. This new schedule is expected to be in place until July.
Why extend the hours?
Extending the hours allows caisson drilling to be completed much more efficiently.
By finishing the day’s drilling during the early hours of the night, the need to take down the equipment and set it back up the next day is eliminated. Also, crews work far more safely and efficiently when trains are not running, as equipment and workers must stand down every time a train passes. Working a few extra hours into the night keeps the momentum going with continued progress and productivity.
What mitigation measures are in place?
Metrolinx has put in place several mitigation measures to minimize the disruption to the community.
This includes sequencing of work to reduce disruption at night. The most disruptive and noisy activities will continue to take place during the day. Night shifts will primarily be used to finish up the day’s drilling, and to cleanup and setup for the next day.
Each caisson takes two full days to complete. One pier is made up of two caissons. Therefore, work will be concentrated in one area for four days, after which it will move:
- Day 1: Drilling
- Night 1: Finish drilling and prep for day 2 activities
- Day 2: Rebar cage installation and concrete pour
- Night 2: Cleanup and setup for the next day
There’s extra planning that’s taken place, to make sure the noisiest things don’t take place when people are sleeping.
Drilling and concrete pours tend to be the loudest activities for this work and have been scheduled to occur mostly during the day. While drilling extends into the early hours of the first night, it is to complete the bottom of the caisson – and noise produced at that depth is less than the noise from drilling near the top. As for concrete pours, doing them in the day means far less equipment moving in the rail corridor at night.
Backup Alarms and Lights
Additional measures to reduce nighttime disruption include no idling of non-essential equipment, using broadband – white noise – backup alarms on trucks and equipment, and pointing lights away from residential windows as much as possible. While crews make every effort not to shine lights directly at windows, this isn’t always possible as crews must be able to see the top of the crane and drill rig boom for safety reasons.
While this work will last until summer, it spans an area from the CP diamond – (just north of Dupont Street) to Wallace Avenue – work during night shifts is localized, and disruption in a particular area is temporary.
The Toronto West Community Relations team has been working very closely with the Davenport community during the project by meeting with key community members on a monthly basis at Construction Liaison Committee (CLC) meetings, where construction impacts are shared in advance. Ongoing discussions are facilitated to listen and incorporate the community’s feedback where possible.
“We have been closely connected with the Davenport community since starting construction, listening to their feedback and concerns on a regular basis” said Luiza Sadowski, Metrolinx senior manager, community relations.
“We are committed to continuing this type of engagement along every stage of the project until it’s completed.”
The Community Relations team posts regular updates on the project website and a new dedicated @GOExpansion Twitter handle. Information is also shared in weekly e-blasts and construction notices, including advance notice for this work, are distributed (hand delivered) directly to all those affected in the community.
Estimate of scheduled work and areas:
- CP diamond to Dupont Street: January 30 to late-February
- Dupont Street to Antler Street: late-February to late-March
- Wallace Avenue to Sarnia Avenue: late-March to end of April
- Sarnia Avenue to Antler Street: May to July
Need a caisson drilling refresher?
Caisson drilling involves drilling a hole into the ground down to more supportive bedrock, lifting in steel rebar cage reinforcement, and pouring concrete. This creates reinforced concrete columns underground that will form structural piers to support the load of the elevated guideway structure above.
A dedicated email TorontoWest@metrolinx.com and phone number 416-202-6911 are available to answer any inquiries or concerns the community has on a regular basis. In April 2020, a virtual open house via Metrolinx Engage provided the community with updates on the project and another virtual engagement is planned for this spring.
Working into the night on any big project asks a lot from neighbours and communities. But the team is working overtime to make sure this work is as efficient and as hushed as it can possibly be.
Story by Teresa Ko, Metrolinx communications senior advisor.