More than 60,000 patients visit the emergency department at University Health Network’s (UHN) Toronto Western Hospital annually. This does not include those who depend on the innovative programs and specialized health care services the hospital provides. To keep the hospital running seamlessly for the community that relies on it, having access to power at all times is crucial in the event of a power outage.
Toronto Western Hospital’s Critical Infrastructure Reliability project is responsible for keeping the hospital running and allowing patient care to continue. Tasked to improve the reliability of the emergency power system, PCL’s Special Projects team and expert trade partners came together to make vital upgrades to the mission-critical backup power equipment.
To update the emergency power system, the team needed to replace the existing generators with two new generators in sound-attenuating enclosures. These generators are supported by a 153-foot exhaust stack. This all needed to be installed within the footprint of the hospital’s central courtyard.
Coordinating the team installing these extremely large pieces of equipment was even more complicated due to the challenging soil conditions of the site. Experts in delivering compact projects under tight constraints, the Special Projects team needed to evaluate the options for how to improve the soil conditions and bring in the heavy installations without affecting the schedule or the budget.
“The geotechnical engineers report identified the existing soil as having low allowable ground bearing pressure,” explains Andrew Easton, PCL Toronto project manager. “With constructability in the winter and a tight schedule as the main two focuses for the team, paving the courtyard with an approach ramp made out of crane mats and steel road plates was the most effective strategy.”
PCL worked closely with the design team to review the imposed loads from the lift to the nearby hospital’s foundations. After careful review, six additional caissons were placed for the main crane outriggers. Temporary shoring was required in the power plant basement to facilitate this lift by allowing loads to transfer from the wall to the basement floor slab.
After assessing the feasibility of the plan, PCL worked with the lift engineer to detail the formal crane mat layout to provide the most constructable, time- and cost-efficient method. Figuring out the correct location for the caisson placement and the crane’s outrigger was key to executing the lift.
With the site prepped, the final piece of the puzzle was transporting the single-piece stainless steel, 112,000-pound tri-stack and generators to their final destination. The challenge was figuring out how to move a 153-foot stack from the east end of the city through the busy streets of downtown Toronto during the day.
“Moving the stack during peak operational hours was not an option, as it would be a disruption for the hospital and the community,” Easton says. “We worked with our trade partners, Ellesmere Fabricators Limited and Anderson Haulage, to have the stack moved early in the morning.”
With the stack assembled to become a part of the truck and a team of vehicle escorts to ensure a quick and safe transportation, the departure began at 3 a.m. PCL intricately mapped out the positions of the cranes to create a clear path of travel when the stack arrived on site. With the stack equal to the length of the entire construction site from corner to corner, the team needed to back the stack into the position which would allow for the tandem crane lift to be completed safely. Slowly, the stack was lifted right from the truck and placed in its final destination by 11 a.m.
“Right before the lift, we performed a final review of the plan with the field team to ensure a safe execution,” explains Andre Bourbonnais, PCL Toronto superintendent. “A project like this requires a tremendous amount of teamwork, collaboration and dedication from our client, consultant and trade partners.”
Following the installation of the stack, the two generators were successfully brought into place. Prioritizing the surrounding community, the state-of-the-art generators produce minimal noise and are enclosed within an acoustic cabinet as an additional sound barrier.
“Complex projects are where we thrive,” says Mark Henderson, PCL Toronto construction manager. “We took a design, developed it substantially to fit the client’s vision and budget and executed it according to plan.”
Recognized for its complexity and innovation, the UHN Critical Infrastructure Reliability project gained national accolades from the Canadian Institute of Steel Construction. On November 10, 2022, the project team, including H.H. Angus & Associates Ltd., Milman & Associates Ltd., First Capital, Ellesmere Fabricators Ltd and PCL, were awarded a CISC Award for Excellence among distinguished members of the Canadian steel industry.
“I am extremely proud of this team for finding an award-winning solution for our client that would enable us to complete the critical lift and overall project safely and efficiently,” Easton says. “The project will have a long-lasting, positive impact on not only the hospital but the surrounding community.”