Efforts to raise the sunken and overturned George H. Ledcor tugboat on the Fraser River are taking longer that expected, while environmental officials claim impacts from the diesel spilled from the wreck have been minimal.

According to Phillip Murdoch, the superintendent of environmental response for the Canadian Coast Guard, the 20 metre tugboat has now been righted but remains underwater.

A larger barge and crane have been moved into place along Sea Island on the Fraser River in an attempt to raise the sunken tugboat George H. Ledcor. (Yvette Brend/CBC)

He said the next step was to lift and de-water the vessel, although windows of opportunity to proceed with the operation were small due to the complications of river currents and tides.

"I'm reluctant to give a timeline. I had hoped we would be up and out by now.," said Murdoch. "Again, these things always take longer than you think it will."

<a href="https://twitter.com/hashtag/fraser?src=hash&ref_src=twsrc%5Etfw">#fraser</a> river busy today as crowd gathers to watch tug boat salvage. <a href="https://t.co/ip0XyRdrIs">pic.twitter.com/ip0XyRdrIs</a> —@ybrend

Adam LaRusic with Environment Canada said his crews had not observed any wildlife impacts from the spilled diesel, including to spawning salmon or birds.

"The sheen was transitory. The salmon are transitory. We don't predict any impact on salmon at this point," he said. "We have shoreline clean-up teams monitoring the situation. They haven't seen much ... but this is an ongoing operation."

A Ledcor official said the investigation into how the tug capsized is ongoing.

Wednesday morning, a giant barge and crane were moved into place alongside the capsized tug, which is now moored at Sea Island on the north arm of the Fraser River between Vancouver and Richmond.

Earlier, divers put a sling around the vessel and plugged vents to prevent more diesel from leaking. However, when the vessel was righted this afternoon, more diesel leaked out.

The radar and mast of the tug is sticking up. But it remains keeled sideways, sitting on the bottom of the Fraser River. <a href="https://t.co/K4pIlqaodr">pic.twitter.com/K4pIlqaodr</a> —@ybrend

Murdoch said all of the new leaking diesel was contained within booms and recovered. He could not say how much fuel has spilled from the tug's 22,000 litre tanks since it capsized late Monday night.

"We are unable to quantify that," he said. "But based on initial observations, not a lot."

Attention: The beach at <a href="https://twitter.com/hashtag/FraserRiverPark?src=hash&ref_src=twsrc%5Etfw">#FraserRiverPark</a> remains CLOSED today as a precaution after tug boat sinking Monday night. Environmental teams continue to monitor shoreline this morning. Recovery operation of tug is now underway. <a href="https://twitter.com/hashtag/Vancouver?src=hash&ref_src=twsrc%5Etfw">#Vancouver</a> <a href="https://t.co/rQLuGLGrM3">pic.twitter.com/rQLuGLGrM3</a> —@ParkBoard

Beaches at Vancouver's Fraser River Park and Richmond's McDonald Beach Park remain closed. Both are popular with dog owners.

"There's also still a strong odour in the area," said City of Richmond spokesman Ted Townsend. "It's gotten better, but we want to make sure it's safe for people and animals."

Beaches in the area, including this one at Fraser River Park, have been closed as a precaution after diesel from the capsized tugboat, seen across the river, started washing up on the sand. (Yvette Brend/CBC)

Dog owner Brian Rackett is a regular at Fraser River Park, which is situated right across from the Sea Island location where the salvage effort is underway.

Vancouver dog owner Brian Rackett is a regular at Fraser River Park, right across from the location where the salvage effort is underway. (Yvette Brend/CBC)

"Hopefully, the impact will be as minimal as possible," he said. "We're really concerned because we don't want anything washing up on the beach and hurting the environment."

Rackett says the park is a popular salmon fishing location and is home to sea lions, beaver and blue heron.

The George H. Ledcor capsized near south Vancouver's Deering Island while towing a barge full of gravel up the river in tandem with a second Ledcor-owned tugboat.

All four of its crew had to be rescued from the water.

With files from Yvette Brend

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