Storms battering B.C.'s West Coast since Saturday (Nov. 14) sent the heaviest rainfall of the province to Squamish, causing an intense few days on flood watch for District of Squamish staff. But high waters receded today before evacuation alerts had to be issued.
From Saturday to Tuesday, more than 105 millimetres of rain fell on the town during a storm that caused floods and wind damage throughout the municipality.
The newly-built Centennial Way underpass was the worst hit area, becoming impassable as a foot of water collected under the Highway 99 Mamquam River Bridge. The water was so high that one local travelled the underpass in his canoe.
Having been built as part of the Highway 99 improvement project, the underpass is still under the maintenance of contractor Kiewit, according to District of Squamish operations director Gord Prescott. A call to a project spokesperson was not immediately returned.
Prescott said he can only assume the construction and/or design of the underpass was flawed, and the drainage and pump system that should clear the water did not work.
"I'm not entirely sure on what has gone wrong," said Prescott.
"You can be assured that our engineering department are pounding on their doors trying to get both the system up and working correctly and to give us direction on how to keep the thing running," said Prescott.
Prescott said it reflects negatively on the district since drivers wanting to use the underpass find themselves detoured by District of Squamish signs showing the roadway is closed. But in reality the municipality fared well through the anticipation of flooding with only a few residents being challenged by blocked culverts.
The Ministry of Environment and River Forecast Centre had forecasted flooding in the Squamish River system, but local rivers rose only to moderate levels and maintained enough capacity to contain the rainfall, according to a district release.
"If it's your ditch or your driveway it might seem a little bigger, but overall in the whole scale of things, they were pretty small problems," he said. "We had road crews 24 hours, and I think they did a real good job in the situation. We went from salting and sanding on Saturday night to 'What are you going to do with all this rain?' sometime Sunday."
The deluge is the result of what Environment Canada calls the Pineapple Express - a flow of moist, sub-tropical air from Hawaii that can cause extreme rain in B.C.
Despite the storm's passing, residents are still being encouraged to check culverts and ditches in front of their properties and clear blockages to ensure maximum drainage and avert some of the usual annual internal drainage issues.
Those unable to clear a blockage are asked to call the Operations Department of the District of Squamish at 604 815-6868.