Count Daniel Genest among those who believe catastrophes come in threes.
In his role as director, coordination for Signature on the Saint Lawrence (SSL), the consortium building the $2.15 billion new Champlain Bridge in Montreal, Genest has been intimately involved in helping the project overcome a myriad of transportation challenges.
“What has been the biggest challenge on this project hasn’t actually been the design or the construction, but the transportation of oversize pieces to the project,” said Genest during a wide-ranging interview with Tantrastudio. In the space of less than a year his team had to deal with the loss of a critical transportation route, weight restrictions on provincial highways and a public sector strike that essentially shut down deliveries.
The new Champlain Bridge project involves the replacement of the existing Champlain Bridge over the St. Lawrence River, with a new 3.4 km bridge (including a 0.5 km cable-stayed portion) that will have six lanes for vehicular traffic, as well as a segregated cycle and pedestrian lane. The project also includes construction of a smaller 470-metre bridge for Nun’s Island, and reconstruction and widening work on Autoroute 15 as well as improvement of the ramps leading from Highways 132 and 10 to the bridge. The new bridge will have a life span of 125 years.
The bridge—scheduled for completion in December 2018— is expected to be used by up to 60 million vehicles a year that will carry an estimated $20 billion worth of goods.
Construction began in June 2015 after SSL, a consortium of SNC-Lavalin, Hochtief, Flatiron, Dragados Canada and Grupo ACS, was awarded the contract by Infrastructure Canada to design, build, finance and maintain the new Champlain Bridge corridor.
According to Genest, 50 per cent of the construction budget was subcontracted to large suppliers and fabricators, $750 million of which went to Quebec-based companies, including $250 million to structural steel manufacturer Canam Group.
A bridge too old
The first shoe to drop, in May 2016, was the limiting of loads permitted on the existing Champlain Bridge by the Jacques Cartier and Champlain Bridges Incorporated (JCCBI). The Crown corporation advised SSL that oversized loads beyond 48 metric tonnes would not be allowed. Four months later the threshold was reduced further to 30 metric tonnes.
“Our construction strategy had over 1,300 pieces coming in from various part of Quebec alone that were impacted by the weight restrictions on the existing bridge,” explained Genest.
The 54-year-old Champlain Bridge is probably the most closely scrutinized bridge in North America, with round-the-clock surveillance. This includes 300 sensors detecting abnormal behaviour in the structure, that are able to send out alerts to engineers 24 hours a day.
JCCBI’s efforts to maintain the structure consisted of installing a series of 100 steel trusses that shore up the exterior girders of the bridge, which had been badly weakened by road salt and corrosion.
SSL’s initial transportation plan was “pretty basic,” according to Genest, with bridge components from four main fabrication locations in the province (Quebec City, Trois Rivieres, Terrebonne and Drummondville) being delivered by road directly to the site using the old Champlain Bridge. “The best way to access the construction site of the New Champlain Bridge was to come in from the South Shore.”
With a fixed schedule, the consortium had to go into “solution mode,” as Genest termed it, once they received notification of the weight restrictions on the old Champlain Bridge.
“We went from a primarily road solution to a multimodal, hybrid solution that is a mix of marine, rail and road,” he added.
“Initially, our first solution was to make greater use of rail. Having railheads in both Quebec City and Trois Rivieres integrated into the fabrication sites, we looked at what we could bring in by rail.”
However, complexity was added to any solution because of the configuration of some of the pieces.
“The pylon and pier segments are heavy, but not large in dimensions, so we had the option to transport them by rail or by barge or by truck,” said Genest. “When looking at rail, we also had to consider the box girders, some of which could not be transported on a rail car because of their size.
“The idea was, let’s see what we can transport by road and complement that with a rail solution. Then we determined that the rail solution was not going to take care of all our problems, so we looked at a marine solution, which allowed us to address box girders of all dimensions, as well as pylon and pier segments.”
Initially, shipping by rail exceeded marine and road transport, but due to the economics of shipping large pieces by rail, it was decided that putting six to eight of the box girders on a ship in Quebec City and delivering them to the Port of Montreal often made more sense than using six to eight rail cars, said Genest.
“Now, the biggest percentage of our deliveries remain by road, with the second—by volume of activity—is by barge.”
The most significant transportation hub at destination became the Port of Montreal, according to Genest.
“There are two railheads in Montreal that we used, including one that is actually in the Port of Montreal, which became a transportation hub for us, where we were able to transload pieces onto marine barges for delivery to the construction site.
“We also created a smaller transportation hub on the South Shore at the Port of Cote-Ste-Catherine and this smaller hub allowed us to address the components that were slated to be delivered to the east approach.”
Just in time
Beyond the weight restrictions on the existing bridge there were road restrictions that were enforced on the provincial road network and, in the spring of 2017, a three-week strike of Quebec government engineers.
The strike created a huge backload because government engineers do the structural analysis that allow the issuance of special transportation permits required for oversized loads.
“We had to adjust our solution along the way, going from essentially a just-in-time delivery strategy to having to implement intermediate storage, using facilities located between Quebec City and Montreal,” said Genest.
None of this was done overnight, though.
“In response to all these issues, we created a very robust logistics management team, which enabled us to plan, contingency plan and set up a system that gave us tight control over all aspects of the logistics plan,” he says.
“It took us a full 18 months to craft this new strategy and implement it.”
Genest says that transportation and logistics was eventually removed from the project’s critical path as they were unable to deliver pieces in a timely fashion to the project. “The immediate impact of losing use of the existing bridge, the additional restrictions on the road network and the strike was the issue of inefficient pre-assembly of box girders and installation.
“The new hybrid solution we implemented, with additional storage, generated delivery delays and in some cases unsequenced deliveries on site.” He cited the example of assembling three box girders, with one coming in by truck, one coming in by barge and the other coming in by rail.
“We’ve been able to overcome these issues—delivery delays, unsequenced deliveries, inefficient pre-assembly/installation—and are now in a steady state of a continuous flow of pre-assembly and installation on site.”