British Columbia

Huge Fraser River ice chunks wash up in Agassiz, B.C.

An earth sciences professors says large chunks of ice formed in the Fraser River and washed ashore near Agassiz B.C. were likely caused by unseasonably cold weather from earlier in December.

Expert says cold snap followed by warmer temperatures and rain caused the ice to break into slabs

Chunks of snow are on the banks of the Fraser River with several people walking among and examining the snow.
People admire and photograph the melting ice chunks on the banks of the Fraser River in Agassiz, B.C. on Friday, December 30, 2022. (Ken Leedham/CBC)

An earth sciences professor says large chunks of ice formed in the Fraser River and washed ashore near Agassiz B.C. were likely caused by unseasonably cold weather from earlier in December.

They were first spotted on the shores near the Agassiz-Rosedale bridge Wednesday afternoon, which is about an hour and 30 minute drive east of Vancouver. 

People have been posing among the ice chunks and posting on social media about the phenomenon.

Chunks of ice are pictured along a river, with a bridge and mountains in the background.
Ice chunks are pictured on the Fraser River near Agassiz Bridge in the Fraser Valley. (Submitted by Valerie Pentz)

'Person-high blocks of ice'

The chunks are a result of unusually frigid temperatures in the province last week, according to SFU earth sciences professor Brent Ward. 

"They're big," he said. "It really shows we had a pretty good cold snap to freeze. It's almost person-high blocks of ice so that's pretty impressive."

Ward said chunks of ice likely formed somewhere upstream in the Fraser River during the cold spell. 

Two people pose next to huge ice chunks along a riverbank.
Valerie Pentz is pictured next to the ice chunks on the Fraser River, some of which are 1.5 metres tall. (Submitted by Valerie Pentz)

Then, with the warmer weather and rain the region experienced this week, the ice broke up into blocks and floated downstream. 

Ward says this commonly happens in colder parts of the province in the spring when river ice starts to break up. He said it is unusual to occur in December. 

Large chunks of ice stick up from the shore of the Fraser River, with a bridge in the background.
SFU expert Brent Ward says it is not common for large chunks of ice to form like this in the Fraser Valley in December. (Ken Leedham/CBC)

The narrow river passage near the Agassiz bridge coupled with the low waterline are likely what caused these large chunks of floating ice to get stuck along the shores, said Ward. 

Ward says sometimes when ice forms a physical barrier it can cause an ice jam. It results in water building up behind it and can lead to rapid flooding. 

But in this case, the ice appears to be melting slowly. 

"I don't think we have to worry about any flooding out there," said Ward. 

Large snowy chunks are on the shore of the Fraser River.
Ice chunks along the Fraser River near Agassiz, B.C., on Friday Dec. 30, 2022. (Ken Leedham/CBC)

Footage taken from the area Friday afternoon show the slabs have begun melting and have shrunk in size.

Ward says people should be cautious if they chose to walk among the blocks, and warns against walking far out beyond the waterline.

Ice chunks like these are not likely to return soon, according to Alyssa Charbonneau, a meteorologist with Environment and Climate Change Canada .

She said temperatures in January are expected to be warmer than normal. 

"At least for now we don't see a return to the cold that we saw during the middle of December," said Charbonneau. 

ABOUT THE AUTHOR

Michelle Gomez is a CBC writer in Vancouver. You can contact her at michelle.gomez@cbc.ca.

With files from Joel Ballard

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