Bridge demolition work requires temporary SUP closure. Here’s why.

The next major phase of demolition work on the east side of the Groat Bridge is set to begin. This means the temporary closure River Valley Road and of the shared-use path (SUP) below the north end of the bridge until the area is again safe for pedestrians, cyclists and other commuter and pet traffic to use. The road will also be closed to vehicles.

The closure takes effect January 20 and is scheduled to last until February 15. These dates, like most of the equipment,  depend on the weather. 

The demolition work will feature 40-tonne Gantry cranes, concrete saws and other equipment to cut through, dismantle and haul away the concrete bridge deck and girders on the east side of the bridge, directly above River Valley Road and the shared-use path (SUP). 

The road and the path are needed as staging areas and transportation corridors during the operation. It is a prime safety consideration that only construction zone workers are in the area while girders, one of which weighs close to 80 tonnes, are taken apart. 

Gantry cranes on Groat Road Bridge

“We really want Edmontonians who use that shared-use path under the bridge to know there is not a nearby detour that is safe—and we studied them all,” said Sam El Mohtar. “It is a much better plan to steer clear of the area and use other routes instead of travelling down into the ravine system expecting that you’ll be able to get through under the bridge during that period.”

A key fact is the uniquely configured roadways that provide access for automobile traffic to and from the Groat Road Bridge, a set-up made even trickier by the zipper merge in place during bridge construction. 

“We hear what commuters not happy with this are saying and we studied the zone extensively,” said El Mohtar. “We looked at each suggested option. Each is significantly high risk and unsuitable for a safe crossing.” 

A City team looked at five possible access points in the area for a detour route. 

Big picture

Here, in greater detail, are the five areas studied and deemed unsafe, and why. 

The view from above

Point A – This is the current location of a temporary crosswalk used by construction workers on site. While this crossing appears to allow access to the west side of the bridge, there is no way to get onto the bridge or onto the safety of the bridge sidewalk that connects to the SUP along Victoria Park Road east of the bridge. Anyone attempting to cross at Point A would still reach a dead-end at the southbound on-ramp. 

Point B – Last year, the City temporarily closed the same shared-use path while demolition and girder work took place on the west side of the bridge. We received feedback requesting that a temporary pedestrian crossing be installed at Point B that would, the suggestion went, allow travelers to go under the overpass and then cross the road to access the bridge at Point D. 

Here’s the challenge: 

Sightlines for southbound motorists coming around the corner under the overpass to this location are not adequate enough to allow for a safe crossing point. Interrupting the flow of traffic at this location would heighten the risk of rear-end collisions. As well, this location is a decision point for drivers proceeding south over the bridge or to Government House Park. Adding foot traffic to this busy point would create an unsafe route for all users. 

(The speed limit through this area is 50km/h. The option of reducing the limit to 30km/h was explored. Speed compliance on arterial roads is typically low. An additional speed reduction would not significantly lower the risk of collision to a level that would make this crossing feasible.) 

Point C – This location was also requested during the last closure and presents similar issues as B. As automobile traffic heads south towards the river, the road curves, establishing the same poor sightlines and conditions as B. Traffic at this point is typically moving  from the outside lane to the inside lane to allow better flow northbound or southbound on Groat, while maintaining access to Government House. As with Point B, there is no feasible way to introduce a safe crossing.

Point D – Similar to the scenario at Point A, commuters, once across the road, would not have a safe option to move onto the bridge. This point would have required temporary crosswalks at location B and C to allow for a complete movement over the bridge to the sidewalk, which is not possible for the reasons explored above. Once again, at this point, the pedestrian would reach a dead end.

Point E – Getting commuters from the open north- and southbound lanes on the west side of the main bridge to the temporary sidewalk, which now runs down the middle of the bridge, and then either north to the ravine trail or south toward Emily Murphy Park, would be the most difficult and dangerous crossing of all. Among other hazards, foot and bike traffic would have to contend with poor sightlines in the current zipper merge environment, a difficult northbound right turn onto River Valley Road, construction traffic and a yield of the southbound ramp from Victoria Park Road. 

In these conditions where the risk of collisions is high, there is no safe place to install a pedestrian signal or crossing that would adequately guarantee the safe movement of people to the sidewalk. 

Projected completion is the fall of 2020 and includes an improved, 4.2m wide shared-use path on the east side of Groat Road Bridge.

There’s more here to learn about the project and its benefits, timelines, costs, closures and engineering.

Thanks for reading the story behind the signs.

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