Rain is kept out of the contained areas so crews can strip and coat the box beam.

On the downstream (eastbound) side of the bridge over the Fraser River, all of the steel required for the deck extension is complete. Crews have poured about 33 percent of the new concrete deck extension on the downstream side. Weather permitting, project manager Dennis Dupasquier predicts the concrete work will progress at a rate of about 7 percent per week.

Work underway on the downstream side of the main span includes demolition of the existing maintenance walkway.

Crews are also recoating the main box beam and part of the steel deck, and installing the permanent roadside barrier. Stripping and coating of the box beam must be entirely contained for environmental and public protection (see photo, center right). Scaffolding encases the entire box beam and a form of "shrink wrap" is installed surrounding the scaffolding to provide a contained work zone.

This view of the Port Mann Bridge shows the downstream side, facing the main span. A steel, orthotropic deck with an asphalt overlay makes up the main span deck. The approach span decks on either side of the main span are concrete slabs.

Crews carefully monitor the contained zone for temperature, humidity and pressure to provide the right conditions for the new coating system. Heaters, dehumidifiers and fans are used to regulate the contained conditions, so work can continue regardless of the weather, which in British Columbia means WET.

Flatiron/KWH started widening the Port Mann Bridge in January 2000 from four to five lanes. Traditional widening was impossible on the main span where the arches descend, so crews have used the old sidewalk area on each side of the bridge to squeeze out a fifth lane for HOV use. The 7,000-foot bridge serves as the major route in and out of Vancouver. It also carries the TransCanada Highway, the longest continuous highway in the world.