08/14/2018 15:52 EDT | Updated 08/14/2018 20:51 EDT

Up To 22,000 Litres Of Fuel May Have Spilled In B.C.'s Fraser River

There are concerns over the impact on the salmon-bearing river.

Andy Clark/Reuters
A salmon jumps while fishers run out their nets at the mouth of the Fraser River in Steveston, British Columbia on September 1, 2010.

VANCOUVER — A tug carrying as much as 22,000 litres of diesel fuel has capsized in the Fraser River between Vancouver and Richmond.

Canadian Coast Guard spokesman Dan Bate said it's unknown what caused the George H. Ledcor tug to capsize early Tuesday, just east of Vancouver International Airport.

There were four people aboard the vessel and all were rescued by the crew on the nearby Westview Chinook tug, Bate said.

The capsized vessel is part of a gravel tug-and-tow operation, but it was not towing a barge at the time. The vessel is about three-quarters submerged and has been secured to pilings, Bate said.

While the tug's fuel capacity is 22,000 litres, he said crews are still assessing the total volume of the fuel spill.

It's unclear what the impact of the spill will be on the ecosystem, which is at the north arm of the salmon-bearing Fraser River.

"Right now it's too early to see what that looks like, obviously it will depend on the quantities and actions that are taken," Bate said.

Booms and absorbent pads have been placed around the vessel by the coast guard and Western Canada Marine Response Corporation, the organization responsible for responding to oil spills along the B.C. coast.

Michael Lowry with Western Canada Marine Response said the company has been retained by Ledcor, which operates the tug, and about 15 bags of the absorbent pads have already been collected.

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He says the pads are put in place when there a "light sheen" on the water but he said it's impossible to tell how much diesel they soaked up.

David Hoff with Ledcor said crews are working to recover the vessel.

"We have a crane on site and divers have already been down to see the tug and they have been down again to assess how we are going to do a lift," Hoff said. "We are hoping to do a lift later on this afternoon and hope to have the craft out of the water by around dinner time."

Along with the coast guard and Western Canada Marine Response, responding agencies include the Environment Ministry, City of Vancouver, Musqueam First Nation and Transport Canada.