Jan 21 2013
Set against a clear blue sky amid a collection of leafy green trees, a row of modern brick townhouses sits in front of a tasteful glass condo tower. In a gourmet kitchen, a pair of freshly poured martinis is poised atop a silver serving tray. As dusk approaches, a group of friends relaxes on a rooftop terrace.
These renderings, posted on plywood walls surrounding a dusty construction site on a residential block near Yonge St. and Eglinton Ave., offer a glimpse of The Berwick, one of dozens of projects set to increase density in booming neighbourhoods across the city, and redefine the skyline.
But peek behind the plywood barrier, and you’ll see a different side of the transformation that is occurring from the waterfront to North York.
Descending about 10 metres below street level, the massive condo hole is supported by concrete walls, hundreds of wooden slats (or tie-backs) and steel bolts and cables, driven horizontally into the ground and anchored with more concrete.
On a late-autumn morning, a soil inspector checks the compaction of the muddy, uneven ground at the base of the pit. He determines it is stable enough to support the footings of the elevator shaft, which workers are preparing to lay.
It’s but a tiny slice of the vital work that is required below city streets to support Toronto’s vertical communities of the future.
“The underground part is really an important part in the story,” said Matti Siemiatycki, an assistant urban planning professor in University of Toronto who specializes in infrastructure finance and delivery.
“It’s the part that happens in the background that the public doesn’t necessarily see … But this is really the precursor that allows you to do all of the exciting mixed-use types of development.”
From parking garages to storm drains, increasing density means overhauling the complex and aging networks of pipes and cables that already crowd the bowels of the city.
However hidden, the infrastructure component is complex and cost-intensive, particularly in older areas, where utilities must be upgraded and expanded to meet rising demand.
“What we’re starting to see now, with the growth and intensification in certain areas in the city, is that we may have little bottlenecks of capacity issues starting to emerge,” said Lou Di Gironimo, general manager of Toronto Water.
More than half of the city’s sewer and water system is between 50 and 60 years old, and about 8 per cent of it is more than a century old, Di Gironimo said.
In the case of the waterfront revitalization effort, which seeks to ready hundreds of hectares of industrial land for mixed-use development, $831 million has been poured into infrastructure since 2001.
But there are challenges to laying the foundations for even a relatively commonplace project like The Berwick, a 17-storey, $100-million condo and townhome development being built by Andrin Cherrytree Ltd.
According to Chris Lloyd, vice-president of construction for Andrin Homes, dewatering the site has been by far the most difficult obstacle.
Because the water table in this area is relatively shallow — about 15 feet below ground — the developer had to install 14 wells around the site to drain it before excavation could begin.
During construction, about 70 gallons of water per minute are being pumped into the storm sewer system. Although the volume will drop to less than half that when the project is completed in late spring 2014, workers will have to take a number of measures to waterproof the footings, a process called “bath-tubbing.”
All of which has slowed down the project and made day-to-day work more complicated, Lloyd said.
Then there’s the location of the triangular site, which is sandwiched between two long-established residential blocks and a TTC-owned property.
To access it, Andrin requested to have the Toronto Hydro poles on the north side of Berwick St. temporarily relocated across the road, in front of a row of detached and semi-detached houses.
According to Lloyd, Hydro distributed leaflets in January to advise affected residents of the proposal, but there were no complaints until work began in August.
“It wasn’t until somebody said, ‘I’m going to put a pole here,’ that they
It took about four weeks of negotiations — and some assistance from area Councillor Josh Matlow — but a compromise was eventually reached. Upon completion of the project, Andrin will move the poles back to the north side of Berwick, and run the high-voltage wires underground.
Because it is a direct result of the development, Andrin will pay the entirety of the $300,000 it is expected to cost to move the poles back and forth, and relocate a portion underground, Lloyd said.
The developer also had to pay to demolish the 20 or so houses that used to occupy the site, and disconnect the gas lines.
Although the former trolley barn at the southwest corner of Yonge and Eglinton hasn’t been used in years, Lloyd said the proximity of the Berwick site to TTC property meant that the developers had to get permission from the TTC before they could start building.
The “Level 2” review, required for all sites located within 15 meters of a TTC property, took several months to complete, he said.
The exact points at which The Berwick will connect to the web of pipes and cables that move water, gas and electricity along Berwick St. have yet to be determined, but it will occur at between 2 and 4 feet below street level, at a cost of about $500,000 to the developer.
At the moment, however, funneling power and water into bathrooms, kitchens and bedrooms still seems a long way off.
On a rainy, mid-January afternoon, concrete support columns jut up from the bottom of the pit, where, despite the wells, water collects in divots in the soil.
But Lloyd said the workers are getting close to another major milestone: laying the concrete slab that will form the base of the parking garage.
“Once we get the slab on grade down, they’ll move quite quickly with the rest of the structure,” he said.
By summer, he predicts, this rare glimpse into the underground will be invisible to passersby.
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