A 60 year old fishing trawler that once worked the waters off Hawke’s Bay has begun a very different life on the seabed, sinking in about ten minutes to become an artificial reef and dive site off Napier. The vessel, named Twofold Bay, was deliberately scuttled around six kilometres offshore near the edge of Pania Reef, where she now rests in roughly 17 metres of water after three years of planning and a great deal of volunteer sweat.
The project was driven by the marine restoration group LegaSea together with the Twofold Bay Charitable Trust, and it drew in local divers, the wider Napier community and mana whenua. The aim is simple enough to explain and surprisingly hard to deliver. Turn a rusting hull into a structure that fish, crayfish and other marine life will colonise over the coming years, while giving recreational divers something close to shore to explore. As 1News reported, the 23 metre steel hulled boat slipped beneath the surface with little drama, which was exactly the point.
Getting a vessel ready to sink safely is the part most people never see. Brett Rigby, who worked on the project through LegaSea Hawke’s Bay and the Twofold Bay Trust, said the preparation ran to hundreds of hours. “It’s been 800-plus man hours,” he told RNZ, explaining that “you have to strip it of everything harmful to the environment.” Crews removed engines, oils and anything that could leach into the water, working to the international standards set out in the London Protocol, the global agreement that governs dumping at sea.
The way the boat went down was carefully managed. Rather than blowing holes in the hull with explosives, the team opened the vessel up so it would settle in one piece. “We don’t want a big explosion and it to blow to pieces, we want to keep the whole boat intact so it’s a really cool dive experience,” Rigby said. To anchor the structure and turn it into useful habitat, the team added about 11 cubic metres of concrete as ballast and placed five pallet loads of ceramic tiles by hand inside the hull to give crayfish somewhere to shelter. Up to 50 reef cones are being set around the wreck to spread the habitat across the seabed rather than concentrating it in one spot.
Over time the bare steel is expected to disappear under a living crust. Chris Scott of LegaSea said the reef would draw in “sponges, green lipped mussels, barnacles, anenomes, and sea squirts,” and that those colonisers in turn would attract fish such as blue cod, snapper and kingfish. Artificial reefs work because they offer hard surfaces and hiding places in waters that are otherwise open and exposed, and they can take pressure off natural reefs nearby by spreading divers and marine life over a wider area.
The decision on where to place the wreck sat with mana whenua. The location was approved through the Mana Ahuriri Trust, and a rāhui, a temporary closure to take and harvest, will stay in place for around 18 months before diving and fishing on the new reef resume. That pause gives the structure time to settle and for marine life to take hold before people start visiting in numbers.
For the people behind it, the scuttling was as much about community as conservation. John Stewart, who chairs the Twofold Bay Charitable Trust, said the work had quietly pulled in support from passers by over the years. “While working on the boat people walking past would always stop and ask about the project and at times donate to the efforts too. History will be made,” he said, according to 1News.
There was a personal thread running through the day as well. The trawler was brought to New Zealand from Australia in 1967 by Kevin Probyn, and his widow Debra Probyn watched the boat begin its final chapter. “Well to me it’s emotional. I think Kevin would be proud, the fact that it’s underwater rather than melted down as steel, being made into god knows what, it now lives out underwater, it’s nice to think of,” she said.
For others the value lies in what the reef will mean for the next generation of local divers. Sandra Mauger, who spoke as an iwi representative, said the project was about keeping young people connected to the sea close to home. “It means the world to me because my drive has been about for the rangatahi of all people, of Hawke’s Bay and broader, that they’ve got somewhere to dive on at home in our own rohe moana,” she said, using the words for young people and for the tribe’s coastal waters.
The reef is one of a small but growing number of deliberate scuttlings in New Zealand waters, where retired ships have been sunk to create habitat and dive attractions rather than scrapped on land. The Twofold Bay sits within sight of an existing natural feature in Pania Reef, and the hope is that the two will work together to lift fish numbers and biodiversity along this stretch of the Hawke’s Bay coast. More information about the project is available through the Twofold Bay Charitable Trust.
What do you think of turning old ships into reefs off our coast? Have you dived a wreck like this in New Zealand waters? Share your thoughts in the comments below.
This article was written by AI, briefed to report the facts, hopefully without some of the bias people bring to the job 🙂
Leave a Reply