Vancouver British Columbia - Construction crews will have to redo a section of a stacked tunnel along Cambie Street after a miscalculation narrowed parts of the tunnel by between 20 and 46 centimetres.
 
The discovery was made when the crew remeasured the top tunnel, which is being excavated along Cambie Street between 11th and 12th avenues, and found two sections were too narrow.
 
One was out by 20 centimetres (eight inches); the other by 46 centimetres (18 inches).
 
The sections, which have already been dug and reinforced with shotcrete, or spray-on concrete, will now have to be redone, said Steve Crombie, spokesman for InTransitBC.
 
This will delay the building of the tunnel, pouring the concrete and adding metal frames, by more than a week and add extra costs to the project.
 
Crombie would not say how much more it would cost to redo the section, which would only require cutting panels out.
 
It's a tricky section, he said, because the stacked tunnel is narrower than side-by-side tunnel configurations. But he added it would not affect the completion date for that section of the tunnel, which is set for the end of December.
 
"It's not going to throw off the completion," he said. "When we're going to pour the tunnel, we want to make sure it's absolutely precise."
 
Crombie said the Canada Line has already experienced a handful of similar miscalculations, which he said are a "logical normal step in the process."
 
He insists such problems are built into the $2 billion extension to the Lower Mainland's rapid transit system.
 
"This is probably the biggest one we've had so far but it's not significant," Crombie said. "One of the beauties of cut-and-cover tunnels is that when you run into problems you can leapfrog and go onto another piece."
 
But Gregor Robertson, NDP MLA for Vancouver-Fairview, said he isn't holding his breath that the project will be completed on time.
 
"They made big promises to all the merchants in Cambie Village that they'll have this part finished by the end of December," he said.
 
"The patience of small business owners on Cambie has long been worn out."
 
Dale Dubberley, owner of Thai Away Home, said she can't take much more of the construction, which was only supposed to disrupt her business for three months. Business is already down 49 percent with lost revenue of $374,000 since construction began, she said.
 
Business owners say they have not been offered any compensation and many have already closed.
 
"I just want this over with, the impact is truly devastating," Dubberley said. "They're creating huge damage to a very small group of dedicated people. I can't understand how this is happening."
 
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