The MV Q of Cowichan (140 meters long) is part of BC Ferries fleet of more than 30 vessels. The owners wanted the on-board Black Water segregated from the Grey Water by diverting the Grey Water overboard and collecting the Black Water in new stainless steel tanks, then pumped ashore to be treated as required. All piping would be Stainless Steel 316L and would need to be installed from the upper car deck down through the three lower deck levels. The project would need to start prior to the vessel's annual maintenance/refit at the BC Ferry fleet maintenance facility in Richmond, B.C.
Once the vessel arrived, we installed the scaffolding and set up fire protection at locations throughout the vessel to make a safe working environment for our workers and other contractors. Our technicians attended the vessel at night, when she was laid up for the lead abatement portion of the project. We also started the prefabrication process at our local repair facility, which included the Stainless Steel piping, the bulkhead and deck penetrations, and the structural seats for supporting the new tanks and equipment.
On the main car deck we cut two large deck openings to accept the new stainless steel tanks, with only inches to spare between the tanks and the openings. When the deck sections where removed we rebuilt the staging then prepared the deck openings and deck sections to be re-welded. Once the openings where prepared, we began to fit and weld the newly prefabricated structural support seating to the bottom shell transverse webs. The structure and welding was inspected by the attending Lloyds Surveyor prior to lowering in and welding the new tanks to the structural supports as required.
Next the prefabricated pipe spools were lowered into the openings for the fit up to start. The new tanks were then connected through the longitudinal bulkheads and along the shaft tunnel to the new pumping station that would be designed to pump the sewage ashore as required.
To complete the project within the short four week time frame, we employed two shifts of over forty trades people, including Steel Fitters, Pipe Fitters, class approved Welders, Insulators, Electricians and Project Managers.