It went about $25-million over budget and inflicted more than two years of delays on commuters. But the buzz on the soon-to-be completed reconstruction of Vancouver's Lions Gate Bridge is that a minor engineering miracle was performed high above Burrard Inlet.
Critics, however, complain it will be a wonder if construction ever ends on the 64-year-old landmark suspension bridge.
For the past 2½ years, construction crews have been rebuilding the bridge, which connects Vancouver's North Shore to the downtown, piece by piece. The bridge now has wider lanes and sidewalks, features viewing platforms and can withstand a major earthquake.
The technological marvel in all this was that the retrofit was done without closing the bridge to weekday traffic.
That meant the work was done on the weekends and at night, during 10-hour time frames -- an engineering feat never before attempted on a bridge that size.
"You're into major, technical calculations with a project like this," said Bob Sexsmith, an engineering professor at the University of British Columbia.
"This has never been done on a major suspension bridge."
But what looked doable and daring on paper ran aground with glitches, delays and soaring costs.
The project, which was supposed to be completed by the fall of 2000, was delayed at the outset when problems arose with the assembly plan developed to rebuild the bridge in short time bursts.
When work crews finally complete the job next month, it will be 18 months behind schedule and commuters will have endured more than 150 bridge closings -- 100 more than originally estimated.
The contractor rebuilding the bridge, American Bridge/Surespan, won the bid on the condition that motorists could still use the crossing during reconstruction.
Assistant project manager Carson Carney said that task was more difficult than first thought.
Last summer, the company submitted a claim to the province for additional money. Under a mediated settlement reached last November, the province paid the company an additional $7.5-million. By then, the price tag had gone from $100-million to $125-million.
The idea to keep the crossing open during the reconstruction came from the bridge's owner, the province of British Columbia. Aging bridges that need to be rebuilt are usually closed for two or three months, during which crews work around the clock replacing panels, section by section.
That wasn't an option with the Lions Gate because closing it would have meant gridlock for tens of thousands of commuters.
Up to 70,000 cars use the Lions Gate each day and there's only one other bridge connecting the downtown to the North Shore.
The bridge's design consultants came up with a scheme in which the work would be done at night, in non-negotiable, 10-hour shifts, between 8 p.m. and 6 a.m.
At night, workers performed a tightly choreographed construction dance, which, on some evenings, called on them to: dismantle a 10- or 20-metre section of the bridge, lower it onto a barge, hoist a new panel into place, then splice it to the existing deck using 800 bolts -- all before morning rush hour.
Darryl Matson, whose Vancouver firm designed the plan, said removing an entire section of a suspension bridge changes its shape. To prevent the bridge from buckling when a section was removed, engineers were constantly adjusting the pressure on the bridge's suspended hangers.
"It involved a lot of tweaking," Mr. Matson said.
But there were hitches. In September of 2000, after the first weekend of deck replacement work, the bridge didn't open until 2 p.m. on Monday afternoon. Cars on the North Shore were backed up for kilometres.
Never again was there a delay that long, but Mr. Carney said he sometimes watched construction through binoculars from his North Vancouver home. If orange sparks weren't streaking across the sky by 10.30 p.m., he knew the bridge opening would be delayed.
"Certainly, it is an engineering first, and in that respect it is a success," Mr. Carney said. "The fact that it was done, that it was able to be done, is really a marvel of modern engineering."