Maple Ridge avoids major flooding from record rainfall

What is likely the wettest November on record in Maple Ridge and Pitt Meadows played havoc with drivers and even trains, and brought fears of widespread flooding.

On Tuesday and Wednesday, as the third of three atmospheric rivers dropped a deluge on Southern B.C., the community braced for the worst.

Maple Ridge sent evacuation notices to hundreds of homes, advising residents living along the North and South Alouette Rivers to be ready to leave.

Volunteers filled sandbags at Maple Ridge Park, where the nearby South Alouette was already overflowing its banks in places. Residents stopped to load the sandbags into their vehicles, to reinforce their properties against potential rising water.

READ ALSO: Maple Ridge prepares for potential flooding

BC Hydro monitored the rising Alouette River – after water in Alouette Lake overflowed the dam early Tuesday – and kept city hall apprised of the situation.

It appeared the worst had passed as of Thursday morning, with drier weather and roads reopened, but the city and Hydro were still on alert.

“Mother Nature decides how much more rain we get,” noted Mayor Mike Morden.

“Appreciate all the volunteers with sandbagging and supply chain relief efforts, and thanks to those on the front lines working flat out. We’re not done yet, lessons to be learned, some already acted upon to support better preparedness.”

RAIN RECORD SMASHED

Environment Canada meteorologist Bobby Sekhon noted it was the wettest fall (Sept. 1 to Nov. 30) on record for both Vancouver and Abbotsford, and very likely places in between. Complete records were not available from the Pitt Meadows weather station.

There were 410 millimetres of rain in November in Pitt Meadows, but data for Nov. 29 and 30 was not available. That’s well in excess of the normal for the month, which is 275 mm, said Sekhon.

By comparison, Abbotsford had its wettest November ever, with 541 mm, which was far above the record of 422 mm set in 2006. Recent rains caused catastrophic flooding on Sumas Prairie.

Sekhon explained an atmospheric river is literally the amount of water that would flow in a land-based river, but contained in the upper atmosphere.

“It’s a long plume of moisture originating in the tropics or subtropics,” he said.

Meteorologists have used the term for years, but has recently been popularized by use in the media.

Sekhon said the Fraser Valley and Coquihalla Canyon both received an enormous amount of rain in the middle of the month. At the Pitt Meadows weather station, there was 91 mm on Nov. 14, and 72 mm the next day.

This immediately caused flooding, and creating the conditions where more precipitation could cause further floods.

In Maple Ridge, flooding closed the Lougheed Highway in both directions between 105th Avenue and 263rd Street, a stretch of 4.8 kilometres, early on Sunday morning.

The West Coast Express commuter train service was interrupted by a mudslide on the tracks in Maple Ridge, near the foot of Fir Street Wednesday night.

Commuters were given a ‘bus bridge’ to get back to Mission that evening, and Thursday morning there was a bus shuttling riders from Mission City and Port Haney stations to Maple Meadows and Coquitlam Central.

CP Rail crews cleared the track on Wednesday evening, and TransLink announced that West Coast Express service was restored on Thursday afternoon.

There were also other local roads closed, including 132nd Avenue and 224th Street. There was so much water, that the Alouette River Management Society reported people finding fish swimming on roadways.

There were also landslides, including one that closed Wilson Street on Wednesday.

READ ALSO: Reports of salmon swimming on local roadways in Maple Ridge reach ARMS

There is a full road closure in effect on 236th Street, between 132nd Avenue and Fern Crescent until Dec. 15, after the road was washed out by an apparent watermain break. It’s unclear if this was flood related.

Golden Ears Provincial Park is reporting trail damage from the storms, noting they were “severely impacted,” but that the extent of the damage and hazards is unknown. BC Parks said trail use is not recommended at this time, and asked people to use caution when visiting the park.

As of Thursday morning, the 800 residents who were given alert notices along the South Alouette were still being asked to have “emergency preparedness plans in place, and be ready to self-evacuate if required.”

Despite the sunshine Thursday morning, the river was still raging and the city had not yet rescinded its warnings.

Among the precautions being asked by city officials, Maple Ridge fire chief Michael Van Dop was encouraging all residents to stay away from the banks of rivers.

This recent series of weather events will prompt some interest, said Morden, who noted the city’s emergency management plans will get an update on technology and implementation procedures.

Cyclical severe weather events come and go, the questions remain on infrastructure, storm systems drainage, diking systems, and so much more, he said, raising the questions of what did we learn, and how do we do better?

READ ALSO: Relief for B.C. as weather warnings lifted; flood warnings and evacuations remain