Four semi-trailer truck rollover accidents in less than two months on the same stretch of the South Fraser Perimeter Road have led Delta Police to sound the alarm over a possible design flaw in the new highway.
The interchange of the perimeter road (Highway 17) at the Highway 91 Connector features a steep downhill slope that also tilts to the outside.
“It’s like someone took a hill and put a bit of a twist in the hill itself off to one side,” said Delta Police acting Sgt. Sarah Swallow.
She said the 12-foot drop in grade to the bottom of the interchange means truck loads can easily shift and that momentum can contribute to a rig tipping over on the tricky tilt.
The interchange accounts for five of six truck rollovers that have happened on the SFPR since it opened.
The latest hours-long closure of the SFPR at that interchange happened Aug. 6 when a truck hauling paint turned over. It took eight hours for both closed to fully reopen because firefighters and hazmat crews had been brought in due to the spill of some paint.
“That one rolled over right into a bike lane,” Swallow noted. “Another one was carrying four large steel pipes. The pipes actually broke free and rolled right across the road.”
Other rollovers have spilled wood, lentils and french fries.
All injuries have been minor ones just involving the truck drivers.
But Swallow fears for the public’s safety if nothing is done to reduce the risk.
“How these have been able to miss anybody so far is amazing,” she said. “If you have a semi truck turning in the inside lane and a passenger vehicle in the outside lane, I don’t want to think about what the consequences of that could be.”
The transportation ministry has ordered an independent review of the design and construction of the interchange to check its geometry and ensure it was built as planned.
“We’re obviously very concerned about the rollovers,” said Patrick Livolsi, the ministry’s south coast regional director.
He said hazard signs will be posted as early as Friday to warn truckers that there’s a risk of tipping, along with a reduced advisory speed limit.
Livolsi confirmed the location is one of three intersections along the South Fraser Perimeter road that was initially built with traffic lights rather than on- and off-ramps as a cost-saving measure. The ministry decided full interchanges throughout weren’t yet justified but critics warned the move would slow trucks and worsen congestion.
Livolsi could not yet say if there would be less risk of rollovers now if it had instead been built as a free-flowing interchange.
“We’re not sure if that’s part of the issue but we’re going to be looking at that.”
The $1.26-billion South Fraser Perimeter Road fully opened last December.
The interchange carries numerous trucks, some carrying hazardous chemicals, heading to and from Delta industrial areas via Nordel Way or the Alex Fraser Bridge.
In some cases the drivers have been ticketed for speed or insecure loads, Swallow said.
“We’re not saying if you made this a flat road the issue would go away,” she said. “But we are concerned this could be a contributing factor to these collisions. The design is amplifying other factors in these rollovers.”
The speed limit there is 80 kilometres per hour, but most of the rollovers have happened at low speed as trucks negotiate the downhill curve.
ICBC hasn’t investigated the safety concerns and was not yet able to provide 2014 statistics on crashes or claims at the interchange.
Intersection of South Fraser Perimeter Road and Highway 91 Connector. Evan Seal / Surrey Leader