Atmospheric rivers bring record rainfall and flooding

Maple Ridge and Pitt Meadows saw record rainfall in November as people became unfortunately familiar with the weather term “atmospheric river.”

There were three such events, bringing an unprecedented amount of rain. The City of Maple Ridge had 800 residents living along the North and South Alouette Rivers on evacuation alert. Roads flooded and were closed, the Lougheed Highway flooded, and a mud slide on the CP Rail tracks stopped train traffic, disrupting commuters on the West Coast Express.

And Maple Ridge and Pitt Meadows were fortunate, compared with other cities.

“This is historic weather, intensified by climate change,” said Public Safety Minister Mike Farnworth as he updated a British Columbia in the midst of its second atmospheric river.

Sumas Prairie in Abbotsford was flooded, leaving farms under water and residents evacuated from the disaster zone. Some 800 farms were flooded in the Fraser Valley. Merritt and Princeton also flooded.

READ ALSO: Ground zero shows flooding of Hwy. 1 in the Fraser Valley

On Nov. 14, Highway 1 through the Fraser Canyon was closed due to a rock slide, and there were also several severe washouts that closed the Coquihalla Highway. There was damage on about 20 sites. Other highways were also affected, and there were a total of about 200 sites, and many routes were open only to essential traffic.

It was the wettest fall (Sept. 1 to Nov. 30) on record for both Vancouver and Abbotsford, and very likely places in between, according to Environment Canada. 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.

Volunteers filled sandbags at Maple Ridge Park to help people in the area prepare for the rise of the North Alouette River.

Coun. Gordy Robson watched the water level rising in the Alouette Lake, as it crested the dam and threatened flooding downstream. He said it was just luck that the rain stopped and there was not more flooding, and said the city needs to consider it a wake-up call.

Ken Stewart, of the Alouette River Management Society, also said the city was fortunate to avoid flooding after the heavy rainfall between Nov. 13 and 15.

“We know this was an extreme event, given how far this went, but this is what we’re predicting now, with climate change,” he said. “This is going to happen more often.”

READ ALSO: More rain would have brought disaster to Maple Ridge, warns ARMS president

According to the Weather Network, B.C. will be under a stormy pattern, and getting more precipitation this winter, which means lots of snow at higher elevations. It’s good for skiers, but not for driving in mountain passes.

Temperatures are also forecast to be lower than usual in early 2022, in a cold weather pattern predicted to last well into February, and perhaps March.