Rescue crews were on alert for potential evacuation of Cheekye Fan residents Saturday night (July 25) as a torrent of debris blocked the area’s river system, threatening a flash flood.

It was touch and go for residents as Squamish Emergency Program personnel and rescue crews stood by for possible evacuation while flood teams attempted to determine why the river’s water was rising.

“Exactly where the water was coming from and how long of a duration it was going to be created some concerns in regards to whether the water was going to continue to rise and whether evacuation would be required,” said Squamish Fire Rescue chief Ray Saurette. “We got geared up for it, and it ended up being a very short duration.”

The debris at the mouth of the Cheekye River continues to create a major blockage of the Cheakamus River, reducing the channel’s ability to convey water flow.

A local geological engineer said action needs to be taken immediately to avoid potential floods. A Ministry of Environment flood hazard assessment team is currently on the scene to determine whether the debris can flow out naturally.

“They’ll be assessing [the blockage] in the next few days to determine whether, over time it will naturally flow away or whether the Cheakamus that’s being restricted… that they’d have to go in there and remove that,” said Squamish Emergency Program co-ordinator Jim Lang.

But geological engineer Frank Baumann, whose done two significant studies on Cheekye River debris flows over the last two decades, says the situation can’t wait.

“A high water event could flow north out of its channel, overtop the dike that is there… and then flow into the village of Cheekye,” he stated in an email to The Chief.

“It is important that this debris be removed as soon as possible before the village of Cheekye is affected by a flood or even high water flow event on the Cheakamus River.”

Baumann said he's been contracted to file a report to ministry officials, and all the authorities and experts involved are "pretty much in agreement" that the debris is too big to flow out naturally. Ministry spokespersons were not immediately available for comment.

The debris came down when thunderstorms washed the Cheekye River basin at the Cheakamus River confluence with heavy rains. The basin’s geography is short and steep, creating a funnelling effect, which backed up drainage, according to Lang.

“The upper reaches of [the Cheekye River basin] are the side hills of Mount Garibaldi,” said Lang.

“They’re 45 degree slopes and the water can come down there pretty quick.

“There’s nothing that obstructs it. If you drop the whole glass in the top of the funnel, it’s going to try and come out real quick and that’s exactly what happened. So the event was short-lived, but the magnitude was fairly large.”

The damage caused the washout of a railbridge used by locals about one km up the Cheekye River. No other structural damage has been reported.

Based on aerial photos and comments provided by Baumann, the team feels no threat of further debris exists, said Lang.

“We’re satisfied there’s no other obstruction up there,” said Lang. “There’s not something up waiting to come down.”