The client
Waterbridge Steel Inc. is a shipbuilding company based in British Columbia, Canada. Waterbridge specializes in building ships in remote sites under difficult environmental conditions with limited access to industrial infrastructure.
The brief
CMDL partnered with Waterbridge in a design-build contract to supply four new cable ferries for the British Columbia Ministry of Transport and Infrastructure. CMDL provided the contract design package as well as full Ship Constructor production package. CMDL also provided quality control services to the yard.
The vessels are accepted into class in accordance with Lloyd’s Register Rules and Regulations with Statutory Inspections delegated to Lloyd’s.
The design
MOTI required four ferries as part of this contract, two of which to have a 9 AEQ capacity and the others a 24 AEQ capacity. The smaller vessels ended up with a 10 AEQ capacity. The 10 AEQ vessel has a length of 30m and breadth of 10.5m. The larger vessels accommodate 24 AEQ with a length of 47m and breadth of 13.5m.
CMDL designed all four ferries to have as many common parts and structures as possible to ensure the efficiency of the project and ease of long-term maintenance. All vessels share the same deckhouse design, machinery, propulsion, engine room layout, cable sheaves and electrical system. The hulls for each design share similar construction details and have the same depth to ensure continuity and momentum for the construction crew and to streamline regulatory reviews.
All of the ferries have the same propulsion arrangement powered by a constant RPM John Deere 4045 diesel engine with 110kW output. Propulsion power is transmitted via a radial piston hydraulic motor to a dual bullwheel traction winch.
The same diesel engine produces all the onboard electrical power via a DC alternator. The alternator output is directed to two large battery banks which supply the main and emergency switchboards.
This project allowed CMDL to expand our knowledge in the finer specifics of cable ferry design. All four ferries operate on very different types of crossings. Some are long with a deep bottom and long wind fetch, while others are short and shallow with high river currents. All crossings must cope with seasonal water level changes. Some with substantial level changes influenced by hydroelectric dam water flow requirements. A single propulsion arrangement was designed to cope with all the extremes at each of the crossing locations.
The build
CMDL was contracted by Waterbridge to control manufacturing quality. CMDL ensured compliance with the design drawings and worked closely with surveyors from Lloyd’s Register. CMDL provided ship inspections ahead of each Lloyd’s surveyor visit to ensure successful compliance.
CMDL attended monthly MOTI site meetings to assure satisfaction from the vessel owner.