VESSEL REVIEW | Whekenui – New Zealand King Salmon acquires fish farm support workboat
A new aquaculture workboat was recently delivered to seafood company New Zealand King Salmon (NZKS).
Designed by Australian naval architecture firm Southern Ocean Solutions (SOS), the all-steel Whekenui will be used in transporting and discharging feed, mort recovery, mooring support, feed barge support, towing, power supply, transporting personnel, retrieving on-site monitoring and photographic data. and general work tasks around NZKS' inshore and offshore leases.
The newbuild has an LOA of 23.9 metres (78.4 feet), a beam of 9.2 metres (30 feet), and a depth of 3.5 metres (11 feet).
Compact streamlined hull coupled with multi-functional layout
The workboat was designed to be flexible and efficient and to be able to perform a multitude of tasks safely and effectively. The hull form was specifically designed to allow higher steaming speeds in rougher weather, while minimising fuel consumption and emissions.
The vessel is powered by two Cummins N855 diesel engines connected to D-I gearboxes. This configuration can deliver a maximum speed of 11.3 knots, a cruising speed of 10 knots, and a bollard pull of approximately nine tonnes.
The propulsion machinery also includes a Cummins 48T 40ekW and two Cummins 6CT 140ekW generators.
Each of the main engines’ output is below 500 hp (370 kW), which SOS said allows for more flexible manning, as well as minimising operational costs. There is also self-contained accommodation for five and a capacity for 100 tonnes of cargo.
To assist with manouevring around fish farms, the vessel is fitted with a 100kW Schottel bow thruster.
Configured for daily heavy duty use
The vessel is equipped with a Palfinger Marine crane boasting full deck coverage as well as a towing/mooring winch and two 1.5-tonne capstans. The large cargo hold features a fully self-contained Akva feed system as well as space for additional salmon feed in bags.
There are also hydraulically operated aluminium hatches designed to be quick and easy to operate with only minimal manpower.
The vessel is also fitted with a mort recovery system so she is able to visit offshore pens each day, feed the fish, recover morts, and verify moorings among other tasks. She was designed to perform well in the extreme weather conditions often experienced at exposed offshore sites.
The electronics suite includes a radar, a depth sounder and plotters from Simrad and radios from Icom.
Whekenui was built jointly by SOS and Z189 Shipyard in Vietnam to Maritime New Zealand survey requirement, and the operational design and construction supervision was managed by SOS.
Whekenui is currently deployed at the NZKS-operated Blue Endeavour, New Zealand’s first open ocean salmon farm. Having launched two pilot pens in April, NZKS is finalising the remaining infrastructure for the site before pilot-scale operations begin in the coming months.
As well as Whekenui, this includes installation of a comprehensive mooring grid, which is currently underway. Once the mooring grid is complete, the salmon will be relocated from the inshore nursery to the Blue Endeavour site seven kilometres off the coast of Cape Lambert outside the Marlborough Sounds.
