Buoy alternative for cruise giants
A Christchurch engineer with OCEL has been working on lowercost solutions for berthing large cruise ships.
Gary Teear has harnessed his experience in designing mooring systems to overcome the multimillion-dollar cost of new wharves.
The type of mooring systems he has been been involved with are capable of holding the biggest ships and have been used in the offshore oil and gas industry, mostly overseas.
He is working on behalf of clients who wish to promote the mooring systems to ports such as Lyttelton Port Company and Ports of Auckland, which have been looking at options for berthing cruise ships.
Teear has also been working on bollard designs and undertaking analysis of mooring loads, using a specialist software programme, for Port Marlborough and Tauranga, which are also investigating options for cruise ships.
A recent proposal to build new or extended wharves created a furore in Auckland where residents opposed more intrusion into the harbour.
The largest cruise ships are longer than most of Auckland’s wharves, requiring a system to secure the nose of the ship.
The bigger problem for Lyttelton Port is funding in the face of pressure from some businesses and local body politicians to build facilities for large cruise ships in the hope their visits will capture tourist spending.
Teear said there were various types of mooring systems which entailed more or less permanent structures.
The system he has been exploring involves a buoy anchored to the sea floor. The buoy can be sunk or removed after the occasional visits of cruise ships.
Ships are tethered to the moorings with anchor chains which are tensioned and capable of withstanding hundreds of tonnes of pressure.
Teear has calculated the loads required and worked out the most appropriate methods.
An example of one type of system used in New Zealand is off the Taharoa minesands at Kawhia where a buoy anchors the ship used to export the sand.