The 186-metre cargo ship Dry Beam is moored at Ogden Point, its massive vertical support beams bent like matchsticks and its load of logs shoved askew by a rogue wave on the North Pacific.

The vessel was en route to Japan from Longview, Washington, when it ran into trouble, lost some logs and issued a mayday call Thursday night about 480 kilometres off northern Vancouver Island.

A rogue wave had pummelled the ship's left, or port, side and caused many of the raw logs on the deck to shift toward the starboard side.

None of the 23 Filipino crew aboard the 26,000-ton vessel was hurt. The damaged vessel limped into port at Ogden Point in Victoria on Sunday, escorted from the high seas by U.S. and Canadian coast guard vessels.

The wave that slammed into the port side was 10-to-15 metres high, said Capt. Jostein Hoddevik, principal surveyor with IMS Marine Surveyors of Burnaby.

"It would have a lot of water behind it, a lot of force," Hoddevik said at Ogden Point on Monday.

He was aboard the vessel to assess the damage and review the incident on behalf of the ship's insurers.

A qualified captain with experience crossing the Atlantic, Hoddevik said there is little the crew could have done to avoid the wave.

The incident occurred in an area of the north Pacific that's notorious for monstrous waves and punishing seas, he said.

The currents and wave patterns combine to make this a highly dangerous area.

"Several of the accidents I've been investigating have come from the same general location — a small area."

The vessel was in the wrong place at the wrong time, he said. "The timing of the wave would be crucial."

Cargo vessels are damaged by waves like this off the West Coast once or twice a year, he said. Sometimes the damage is relatively minor and the vessel can continue on to its destination.

At times, the vessel must return to port for repairs.

The cargo ship lost a few of its logs and others were dangling off the starboard side as it arrived in Victoria.

The vessel will need extensive repairs before it is seaworthy again, Hoddevik added.

The bent stanchions on the port side will be cut off, and the logs removed and put on another ship or barge.

smcculloch@timescolonist.com