A highly rudimentary method is being pursued by the BC Ministry of Transportation as the temporary solution for removing snow and ice from the Alex Fraser Bridge.
In a release, until it can find a permanent solution, the provincial government says it will utilize a heavy-lift helicopter to clear the bridge cables of any snow during the expected snowfall this weekend. High winds from the rotors will blow away any snow that accumulates on the suspension bridge cables.
“The first was a large amount of snow accumulating on the cables. Most years, there is very little snow or the snow blows off without accumulating,” reads the release. “The second factor was the cycling of temperatures and wind direction, which increases the likelihood of shedding snow and ice.”
With the temporary helicopter method of clearing the snow and ice, any bridge lane closure times should be limited to two to three hours.
With the Port Mann Bridge, the cables span over lanes of traffic to meet with the bridge towers positioned at the centre of the structure. This caused snow and ice to fall directly onto the lanes of traffic below, and it prompted the provincial government to install a de-icing system of cable collars shortly after the problem was identified.
A chain-link collar ring weighing 10 kg is manually released at the top of the suspension bridge’s tower. As it speeds down the 288 cables, it clears any snow and ice buildup.
The provincial government says the cable collar system has been effective in clearing the cables of snow, and crews will continue making snow-clearing drops this weekend if necessary.
Unlike the Port Mann Bridge, the cables of the Alex Fraser Bridge are located on the side of the bridge. But its traffic lanes are still prone to falling ice and snow when high winds blow any falling ice towards the direction of the bridge.