The bridge money-hole gets deeper

By David Broadland, April 2012

Massive design changes to the new Johnson Street Bridge were withheld from City councillors prior to a critical vote.

AT A CRITICAL MOMENT in the special council meeting held March 15 to consider whether to keep digging the Johnson Street Bridge money hole, City of Victoria councillor Marianne Alto said, in effect, “Let’s keep digging.”

Along with other councillors, Alto had just watched a PowerPoint presentation by the City’s prime consultant, Joost Meyboom, the bridge’s architect, Sebastien Ricard, and the City’s Mike Lai.

Considered to be a swing vote on the question of whether to keep digging or get out and look around for what else might be possible, Alto declared she could now “understand” why the price had risen to $92 million. She told her fellow councillors she felt “grief” when she first heard the new price and earlier that day had decided “$77 million and not a penny more.”

Although I asked Alto for an explanation of exactly what changed her mind, by press time I’d received no response. Could it have been the dozens of images of beautiful, dramatically-lit swooping cable-stayed pedestrian bridges that Ricard’s employer, Wilkinson Eyre Architects, has designed? Or might it have been the confidence-instilling statements by Meyboom that every step so far in this “complex” project had been executed with such amazing ingenuity that buckets of the City’s money had been saved already. Well, we don’t know.

But one thing that didn’t contribute to Alto’s decision was the content of slide 24 in the Meyboom-Ricard show. An image was flashed on the overhead screen for about 6 seconds. No explanation was given other than Ricard’s brief statement that “This is some of the mechanics of the mechanism for the wheel to rotate.” After blasting past slide 24, Ricard lingered at length on slide 25, extolling the virtues of the design of the new bridge’s railings.

The implications of what was on slide 24 are perplexing (See images of the old and new mechanical systems at the links below). It shows the new bridge’s mechanical system—the arrangement of gears and motors used to lift the bridge for passing marine traffic. And it’s completely different than what the engineers had been saying would lift the bridge’s bascule leaf. For you railing freaks this probably doesn’t sound very exciting. But what’s important here is that a major design change had taken place, and at the very moment councillors needed full disclosure to be able to make the best decision for taxpayers, this vital piece of information was withheld.

Why did Meyboom and Ricard avoid telling councillors about the change? What was wrong with the previous design they had confidently claimed was tried and true? Are they any surer about the latest design than they were about the first? Has its cost been fully figured into the latest cost estimate? What other implications are there?

I explored with a bridge engineer the ramifications of this change in terms of functionality, long term reliability, and cost.

First off, the geometry of the new mechanical arrangement eliminates the very feature that convinced many people this bridge would be “iconic” and “cool”—the ability to walk through the rolling bascule rings while the bridge was being lifted or lowered. Slide 24 shows the bridge deck has been extended about 15 metres to the east of the bridge’s centre of rotation. (In the initial design it ended west of the centre of rotation.) With the new design, that long tail will swing 15 metres down into what’s called a counterweight pit, and would knock out any walkway that floated between the rings. So in the new design the walkway hangs from the underside of the bridge deck and would rotate when the bridge is raised.

The rotating walkway will create concerns about safety and liability. How will the engineers ensure no one is ever trapped on that walkway as the bridge is raised? Will they soon be arguing that it would be best to elminate the rotating walkway altogether? Moves in that direction have already been taken. City council was told recently the walkway would not be connected until some “future date.” Is that another way of saying “never”?

Another issue is reliability. In the initial design, the rings had circular gear racks driven by motorized spur gears located directly beneath the rings. This compact arrangement of machinery would not have been exposed to whatever debris fell from the bridge deck. But the new design has an exposed gear rack that sweeps in an arc six storeys down to the bottom of the pier building. Anything that comes off the bridge deck as it is raised—sand, gravel, nails, car-body screws, ice, chunks of the roadway itself—is going to fall toward the gear rack. Eventually, something will land or bounce onto that rack. When a stone or a spike finally lodges between the teeth of the gear rack, the gears will be damaged when the bridge is lowered, possibly putting the bridge out of operation for an extended period.

Bridge engineer Frank Nelson noted that with the new design, the driving mechanism is located a relatively great distance away from where the two big rings of the bridge rotate on rollers. For this design to work, he notes, the rings would need to be machined to exceedingly high tolerances. Nelson said, “This is not a typical fabrication technique.” It will require “a major part of the truss to be fabricated to microns as opposed to millimeters. This is closer to aerospace tolerances.” Could such work be done in this country? “Canada has aerospace shops that could do this,” Nelson said, “But then there is the matter of joining those fabrications to the rest of the truss and not introducing weld or fit-up stress in the truss.” Can it be done? “I am sure it can be done,” Nelson said, “but for a contractor to figure this all out in the period they have to prepare a bid will introduce significant risk pricing, which may not yet be figured into the estimate.”

Would a mechanical system that required such exacting tolerances survive a magnitude 8.5 earthquake? Nelson said “I am not aware of a moveable bridge with this two-rings-in-roller-cradles design in existence in a high seismic zone.” He reckoned that with this mechanical system the cost of the bridge “will likely exceed $100 million by the time it goes to construction.”

Let’s summarize: The bridge has lost the one unique quality which people agreed would qualify it as iconic—the walk through the rings while the bridge is in motion, a feature promised in a referendum. And now the geometry of the new lifting mechanism will require those rings to be machined to such extremely high tolerances that they will be exceedingly expensive, and that’s probably the real reason the cost estimate has ballooned. But the only reason for including these exceedingly expensive rings in the design is so that people can walk through them when the bridge is in motion.

The design rationale has become illogical and that fact was hidden from Marianne Alto and other councillors when they voted on March 15 to keep digging.

 

AT A MARCH 22 City of Victoria council meeting, councillor Geoff Young questioned City staff about changes to the bridge’s mechanical design. Project director Mike Lai told Young, “There has been no material change in the design,” even while admitting it would no longer be possible to walk through the rings when the bridge was in motion.

Engineering department director Dwayne Kalynchuk told Young, “It’s a complicated process in designing this bridge...there’s not another bridge we can go and look at and say ‘Yep that’s how it’s gonna look and that’s how it’s gonna operate.’”

Young expressed reservation about being a bridge design pioneer: “All the discussion about the design evolving because it’s unique and because this is the first time it’s been done— that’s exactly what is worrying me. I don’t want to be in the forefront of bridge design and at the same time [be] assuring people that we’re going to be able to bring it in at the budget we’ve set out.”

Councillors went on to ratify the motion they passed a week earlier, moving forward on what is, for now, a $93 million bridge. Councillors Young, Lisa Helps and Ben Isitt voted against. Councillor Gudgeon was absent. 

Some members of this council—Mayor Fortin and councillors Coleman, Madoff and Thornton-Joe—seem to have lost all perspective about the costs and benefits of this project. They seem able only to say “yes” to the City engineers, who have in turn been captured by the Meyboom-Ricard corporate show.

Even in the face of a massive and expensive design change, the City’s engineer says “there has been no material change.” Mayor Fortin nods his head and says there has been no material change. Each time there is “no material change,” the functionality of the bridge goes down and the price goes up. Each time the price goes up, the only winner seems to be Meyboom’s MMM Group.

Bit by bit, the original design parameters are disappearing: First rail was removed. Then design life for the approach bridges was dropped to 75 years and the navigational channel width shrunk from 47 to 41 metres. Now the walkway through the wheels is going to be eliminated. What’s next? The safety space on the outside of the bicycle lanes? Whoops, that’s been eliminated too. Ka-ching, ka-ching, ka-ching.

In April 2009, Fortin, Coleman, Madoff and Thornton-Joe voted to replace the bridge when they were told the cost of a “signature” bridge would be $40 million. Including a few of the councillors’ “must haves”drove that price to $63 million. Once the Wilkinson Eyre concept had been cost-estimated, the price grew to $89 million. When rail was taken off it dropped to $77 million. Now the price has grown to $93 million. Will that be the end of the money-hole digging? Only if Marianne Alto puts down her shovel.

David Broadland is the publisher of Focus Magazine.

 

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