DEH GAH GOT'IE KOE/FORT PROVIDENCE - The Deh Cho Bridge will be opening a year later than planned.

Originally scheduled for completion in 2010, the bridge construction will now stretch into an additional season in 2011, said Kevin McLeod, the director of highways and marine services for the Department of Transportation.

Kevin McLeod, left, the director of highways and marine services for the Department of Transportation discusses the revised timeline for the Deh Cho Bridge project during a media briefing in Yellowknife on July 27. The bridge is now expected to be complete in the fall of 2011, a year later than planned. - Andrew Livingstone/NNSL photo

The department held a technical briefing in Yellowknife on July 28 to provide an update on the project's status.

The delay has been caused in part by the findings of a review of the bridge design. The territorial government in conjunction with their advisors, the engineering firms BPTEC in Edmonton and T.Y. Lin International in San Francisco, conducted the required independent review of the original design for the bridge submitted by the Deh Cho Bridge Corporation.

The foundations, piers, pier abutments and earthworks were all fully endorsed in the April 2009 report with some minor modifications, said McLeod.

The report, however, made a number of recommendations concerning the bridge's superstructure including the trusses, pylons, cables and bearings. The recommendations were forwarded to the Deh Cho Bridge Corporation's design team who have already addressed the main issues.

Because of the changes, ATCON Construction, the primary contractor on the project, was advised not to proceed with the fabrication of the superstructure and deck until the design was finalized, said Andrew Gamble, the corporation's project manager.

The actual design changes aren't significant and can't be picked out on drawings of the bridge, Gamble said.

"They're mostly what I would call detail," he said.

The changes include a slightly different manufacturing process for the prefabricated concrete deck that will be simpler and lighter as well as some changes to the bearings and suspension joints.

"It will improve the design and we believe simplify both the fabrication and erection of the superstructure," said Gamble.

The design amendments are expected to be incorporated and approved by the territorial government by the end of the year, Gamble said.

The costs of the design modifications aren't fully known.

The price may actually come down as the result of the changes that have simplified the construction process, he said.

The cost of raw materials including fuel, concrete and steel has also decreased from the initial project start costs.

The bridge currently has a $165 million price tag. Once the design modifications are finished, the Deh Cho Bridge Corporation will determine any new costs, McLeod said.

The government isn't apologizing for allowing the bridge to go ahead without a final design. Decisions were made with the information at hand, said McLeod.

The technical team knew the construction of the superstructure was over a year away and that the piers and earthworks had already been checked so they wouldn't be affected.

"We took a risk," said McLeod.

It was decided that the risks could be mitigated and that any necessary changes could be made, he said.

"So far it's proving useful. We're getting a better, easier, faster, stronger design," said McLeod.

The resulting delay in the project isn't uncommon for a civil engineering mega project like the bridge, he said.

"Given all that's happened, we're in a great position," said McLeod.

In addition to the construction timeline and the bridge design there's also been a reorganization of the duties between various contractors on the project.

ATCON is still the general contractor for the project. The company is responsible for the fabrication of the steel pier bents, the steel armour, the superstructure and the deck as well as the operation of the construction camp.

Ruskin Construction was a sub-contractor to ATCON responsible for building the temporary bridge, the cofferdams, the concrete piers and the installation of the steel pier bents. A contract dispute between ATCON and Ruskin that resulted in a short work stoppage early in the construction season, however, prompted the Deh Cho Bridge Corporation to take action.

As of July 24 Ruskin is now in a contract directly with the corporation to complete its original work. Ruskin will now also be producing the aggregate and the concrete for the piers.

Rowe's Construction of Hay River, a sub-contractor to ATCON, which was doing the earthwork approach, the aggregate and the concrete is no longer involved in the project, said Gamble.

Ruskin's intent is to use a Northern company for the concrete work. A tender will also be put out shortly for the remaining earthworks. It's expected to go to a Northern contractor, said Gamble.

Work is currently underway on the site to install the temporary bridge and prepare the cofferdams for the four new piers that will be constructed on the north side of the river this year, Gamble said.