The St. James Civic Centre in Winnipeg, Man., is getting the space and modernized program its community has asked for: a 15,000-square-foot expansion with flexible multipurpose rooms, a community kitchen, a new studio and a proper home for the St. James Assiniboia 55+ Senior Centre.
While renderings display a beautiful and welcoming facade, the true story lies beneath – 152 cast-in-place caissons that make it possible. These foundational pillars transfer loads to dense glacial till, chosen for their strength, reliability and minimal impact on nearby homes.
This unseen work is the backbone of the project. Additionally, the project remodels the main building entry and reconfigures the parking lot to enhance circulation and access, making it safer and more convenient for users. These upgrades will improve visitor experience and community accessibility, while also targeting LEED Silver certification, reflecting a commitment to environmental sustainability and reduced operating costs. The City of Winnipeg has confirmed an approved $17 million budget comprised of tri-level support from the municipal, provincial and federal governments. The project broke ground in June 2025, with plans to reopen in fall 2026.
Winnipeg’s subsurface is layered: cohesive clays near the surface, glacial till beneath, then fractured limestone bedrock. These clays are known for seasonal movement. Shallow footings risk differential movement, cracked finishes and doors that won’t swing properly. “Here, you’re building on deep foundations, period,” said Jonathan Schinkel from Sub100, who consulted on the piling scope and supported the contractor, Metro Piling, on the execution.
The structural team’s tendered design called for the bored piles to end-bear in the dense till, rather than to the bedrock, with shaft friction along the embedded length contributing to capacity. Pile tip elevations varied across the grid to match actual till density. In practice, typical lengths ranged from 8.5 to 9.8 metres (m), and the 762 to 1,016 millimetres (mm) class diameters were used to meet capacity and stiffness targets.
Schinkel has been involved in drills since he was 15, running a rig in a rock quarry for his father before university. He moved from estimator to general manager at a major piling firm, then stepped away from corporate life to launch Sub100, a consulting firm that still pulls him on-site with contractors. He also advises owners directly, including acting as an owner’s rep for the International Institute for Sustainable Development’s Experimental Lakes Area facility, translating field realities into better decisions.
“Piling isn’t glamorous,” he said. “But it’s what everything else depends on.” That perspective guided his approach for the St. James Civic Centre expansion: a practical plan with contingencies, executed cleanly, for a smooth superstructure team hand-off.
Winnipeg builders insist on deep foundations because the soil science supports it. Local studies report thick, high-plasticity clays – often interlayered montmorillonite–illite – with up to 80 per cent clay content and thicknesses to 20 m; conditions prone to swelling, shrinkage and settlement if built shallow. Below, glacial till over dolomitic/limestone bedrock adds complexity, characterized by patchy density, soft seams and sometimes pressurized groundwater. End-bearing cast-in-place caissons into dense till have become a Winnipeg standard for civic and commercial work: bypassing clay movement, seating into a strong layer and keeping serviceability high.
The technical documents and field work were co-ordinated across a diverse project team, including the City of Winnipeg, LM ESP as the architectural and program lead, Tower Engineering Group for structural engineer and pile scheduler and TREK Geotechnical Inc., to conduct the geotechnical investigation and provide bearing recommendations. Bird Construction is the prime contractor running the site. Sub100 provided piling consulting and oversight, while Metro Pile handled field drilling and pouring.
Unlike design-build foundations, where contractors help shape the solution, the St. James pile package was pre-designed. Capacities, diameters and performance criteria were set by the design team based on geotechnical data. Sub100 and Metro Piling focused on buildability, managing groundwater risk at the till interface and ensuring schedule certainty through proper tooling and sequencing.
The crew mobilized a Soilmec SR-20 rotary rig – well-suited to the project’s pile diameters and depths – run by a single crew. SR-20 is a compact, high-torque machine, rated for approximately 100 kilonewton metre featuring a roughly 156-horsepower plant and maximum pile diameters of around 1,200 mm. It has a nominal maximum depth of approximately 32 m with a standard setup. The sequence was fluid: layout, drilling and cleaning to the target tip in place, followed by a geotechnical inspection, cage placement and continuous pour.
The crew worked under Notice to Airmen and airport zoning height limits for nearby Winnipeg Richardson International Airport. “At the end of the day, it was fine; we were significantly under it. You throw in a permit, call it a day,” said Schinkel. In practice, the rig and support gear stood well below the flight paths and height restrictions, allowing for straightforward permitting and no impact on production tempo.
“You don’t notice great foundations. You notice when they weren’t done right.”
Jonathan Schinkel, Sub100
The site’s suburban location simplified common logistics: easy access made trucking, staging and material handling straightforward, helping the crew maintain workflow. Safety focused on open-hole fall protection around large shafts. The team managed this with covers, signage, an exclusion zone and supervision. Downtown constraints didn’t limit the site, and the Bird Construction site team and geotechnical consultants responded quickly to field notes. “Anytime we hit sub-par material to bear on, the team turned in responses quickly,” Schinkel said. “From our perspective, it was an excellent job.”
An advantage of bored cast-in-place shafts for this project was the low noise and minimal vibration near an active arena precinct and established neighbourhood. That helped the team maintain a good neighbour profile while keeping production steady. The most significant risk identified in the pre-construction phase was potential groundwater contamination where the till meets the bedrock. The team carried an allowance for temporary casing into the till to guarantee hole stability and a clean bearing. Field conditions surprised on the upside.
“We lucked out,” Schinkel said. “The till at the top was incredibly dry. Either you had dry and perfect, or if you didn’t, you went deeper and it got softer, but we could adapt.”
Adaptation involved occasional upsizing at a handful of locations where the till didn’t quite match the report’s predictions. Rather than chasing extreme depths, the field team and geotechs agreed to increase the diameter to regain capacity, keeping production on track without overspending the schedule. With that approach, the piling phase wrapped up in about four weeks. Schinkel says the piling scope ran about $750,000, or roughly 4.4 per cent of the City’s $17 million project budget.
A geotechnical inspector witnessed every shaft: recording depths, till characteristics, bearing conditions and concrete deliveries. Because LEED Silver is a goal, the piling team tracked rebar cut-off, concrete haul distances and local sourcing – inputs for a sustainability submission. On paper, Winnipeg’s till and rock contact zone can be problematic: soft seams, water in fractured limestone and local variability from glacial deposition. That’s why the team priced a casing contingency and stayed flexible on pile lengths and diameters. In the end, seasonal dryness in the upper till proved to be the gift that kept the work uncomplicated. Where the till was a bit soft, the solution was to increase the diameter over depth.
Schinkel’s view of success is modest by design: no drama, no surprises, just capacity achieved and a clean turnover. “You don’t notice great foundations,” he said. “You notice when they weren’t done right.”
Experience on Winnipeg’s soil shapes construction success: knowing when to carry casing, upsizing or halt drilling. This expertise builds an unseen support system that keeps floors level and community spaces functional for decades – a quiet achievement few notice, but everyone will rely on long after opening day.