How the city is overhauling Crowchild Trail's river crossing without ever closing it

The mammoth job of revamping Crowchild Trail where it crosses the Bow River is more than half finished, but some of the most challenging work is just starting as workers add two lanes and rearrange off-ramps while 100,000 vehicles per day continue to drive above and around them.

The City of Calgary's two-year, $84-million project will add an extra lane to northboundand southbound Crowchild Trail between Memorial Drive and Bow Trail and relocate the on-ramps from westbound Bow Trail/10th Avenue over to the east side of Crowchild.

And the off-ramp to Memorial Drive has already been moved farther north, so that vehicles merge onto that route from the left lane.

"Keeping this road open on these bridges with traffic flowing on top of them throughout the project had to be a priority, obviously, because commuters and businesses and emergency services all depend on using this road 24/7, 365," said senior transportation engineerJeff Baird.

To accomplish that, crews needed to get several temporary structures in place before the work of widening and altering Crowchild Trail could get underway.

The first step was to widen the roadway's basewithout impacting the safety of the traffic below, said Martin Dobby, the senior project manager with Graham Construction.

"We have to get down to the foundation level. So to do that safely we had to install a temporary wall which is holding up 10th Avenue. That allows us to work right the way down and we're nearly nine metres below 10th Avenue level," he said.

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"And that allows us to install the wider pier and then we'll soon be constructing the pier cap itself, which is the base substructure which supports the beams and girders above."

The girders allow the bridge deck to be extended on average by four metres, and as much as 6.5 metres at some points.

A temporary work deck was also attached just metres below the traffic to keep the workers safe while construction is underway. It's been called a bridge underneath the existing bridge.

"It forms a solid platform so that our workers aren't exposed to fall hazards. And it prevents material and debris from falling into traffic or trains below," Dobby said.

"It allows us to carry on with all of the work above the traffic without interfering with it."

The project includes about 1,500 square metres of concrete surface rehabilitation, about 50 kilometres worth of reinforcing steel dowels to support the new structures, and about 16,000 square metres of new asphalt.

In total, there are12 different improvementsto CrowchildTrail and surrounding roads, as well as nearby pathways.

Baird says the project is on budget and set for completion by the end of 2019.

Crowchild Trail upgrades explained

7 years ago

Duration 0:47

The nuts and bolts of how the road construction will affect you over the next two years.

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