The Magazine for Underwater Professionals
SEAMOR Marine helps in recovery of sunken tug
When two tugboats collided off the coast of Nanaimo, Canada, in late May 2016, Canadian firm SEAMOR Marine was quick on the scene to offer help.
The accident occurred on the evening of 24 May in the south of Nanaimo between Duke Point and Gabriola Island, British Columbia. Two tugboats were running alongside one another, when one ship, the CT Titan, swerved and crashed into the smaller Albern tug. Two crew members were safely pulled from the water, but the Albern rolled and sank to the bottom of the Northumberland Channel.
The sunken tug suffered damage to its fuel tanks, slowly releasing fuel into the channel at the rate of five-foot (1.5-metre) diameter patches of oil every 10 minutes. At 105 metres of depth, with substantial tidal impacts and moderate current in the channel, there were concerns that the oil spill could worsen.
SEAMOR Marine, an ROV design and manufacturing company in Nanaimo, offered assistance to the Port Authority immediately upon hearing of the accident. With its state-of-the-art ROVs, the company could help identify the exact location and position of the boat underwater.
“If something happens in our waters, we want to be there to assist,” says Robin Li, president of SEAMOR Marine.
As soon as weather conditions permitted a site visit, Li and SEAMOR mechanical engineer Adam Penner accompanied a captain, deckhand and an ROV pilot (Chris Dumas) from the Port Authority to inspect the shipwreck.
Two ROV dives were scheduled to pinpoint the location of the sunken ship on 14 June. While there was some GPS information from the ship’s crew, it was not known where exactly the tugboat lay underwater. The Chinook ROV (SEAMOR has named its vehicles after local species of salmon) can be equipped with sonar – an Imagenex, Canada, 852 sonar gave the team the ability to quickly determine the location of the tugboat, much faster than one would be able to find it visually.
Next, the SEAMOR Chinook was used to do a full inspection of the sunken tug, including confirming the identity of the ship. The clear video from the ROV’s camera was saved to an onboard digital video recorder. This video has been shared with the Port Authority and will also be reviewed by a salvage contractor to establish a recovery plan.
The Chinook ROV used is a fully redesigned vehicle that was launched by SEAMOR in Spring 2015. The company says that, compared to other, older vehicles in this inspection-class, the Chinook is very manoeuvrable, has more power and moves smoothly both in still water and heavy currents. It is rugged, built to handle tough work and is easy to use by the most novice ROV pilots, the firm adds.
SEAMOR ROVs have been used for shipwreck inspections and recovery across the world. The vehicles’ applications are widespread too, as they have been used in a variety of fields, from aquaculture to dam inspection and underwater archaeology to pipeline inspection.