A mistake early in the planning process has forced construction crews to backtrack on a two-storey underground parking garage that was supposed to be part of the new Whistle Bend continuing care facility.
When the territorial government went looking for a company to design and build the new project it mistakenly told builders groundwater could be drained into city storm sewers.
That’s not true. Whitehorse’s system is designed to manage surface water but not a constant flow of groundwater.
Steven Leeming, the territorial government’s project director for the Whistle Bend facility, said at this point they don’t know who made the mistake.
“Obviously it’s something we’re looking at,” he said.
Planners met with the city about the project last year but groundwater was not specifically discussed, he said.
It was only this January, when PCL Constructors Westcoast Inc. presented its plans to the city, that the problem was uncovered.
Wayne Tuck, the city’s manager of engineering services, said he was told the two-storey facility would be dealing with 144 cubic metres of water per day. “That’s a lot of water,” he said, and not something the system is designed to manage.
“We were all hoping that we would be able to accommodate the original concept design in full with just a few tweaks and technical solutions to the problem,” Leeming said.
But that didn’t pan out. So now the garage is being shrunk from a two-storey, 150-space facility to 75 spaces in one storey. All the parking that would have been on the second level will now be above ground, Leeming said.
The water table in Whistle Bend is about 4.5 metres underground, Leeming said. A one-storey garage is “maybe just a few inches into the water table,” he said.
The smaller garage is being prepared to deal with water issues if they come up.
The garage will be attached to the city system for surface water, which will work fine in the summer months, Leeming said.
Crews are also adding a 250 cubic metre storm water tank to the design. It will collect surface water if there is a major storm, or potentially store water in the winter in the event of a major melt.
“What we’re not allowed to do is drain the surface water in the colder months because that could cause glaciation in the storm water system which obviously would not be a good thing,” Leeming said.
The tank would be emptied in the spring or could be pumped out earlier if it got too full.
Meanwhile, crews that were digging the hole for the two-storey garage have had to backtrack.
Leeming estimated the hole was down to what would have been the top of the lower level of the parkade. PCL has had to backfill about two metres, he said.
The cost of the changes hasn’t been worked out yet but Leeming said everything will be covered using the project’s contingency fund.
“We’re very confident that the project remains on budget.”
The Whistle Bend continuing care facility is slated to have 150 beds and to open in the spring of 2018.
The three-year project’s total budget is estimated at $146,600,000. Roughly $113 million of that is to pay for the design and build. It’s one of the largest construction contracts ever awarded in Yukon.
The facility has been the source of controversy since it was announced. The opposition parties accuse the government of wanting to warehouse seniors in an underdeveloped neighbourhood away from their communities. The government maintains that the Yukon is in desperate need of continuing care beds.
Contact Ashley Joannou at firstname.lastname@example.org