Construction of the $530 million Belmont Desalination Plant has reached a major milestone, with the completion of the 830-metre intake tunnel.
A tunnel boring machine recently broke through to the offshore intake location before it was safely recovered from the ocean.
"Rhiannan", the TBM named after Belmont local and world champion cliff diver Rhiannan Iffland, was used to install the 2.4-metre diameter pipeline beneath the seabed.
With TBMs rarely retrieved from the ocean floor in Australia, recovering the machine marks the completion of one of the most complex and high-risk components of construction on the project.
The recovery followed a carefully planned sequence of offshore works carried out over several weeks.
Specialist divers first removed debris from around the machine before positioning and aligning a support cradle to guide the TBM into place ahead of retrieval.
Once safely sealed and stabilised, divers connected the hydraulic recovery system, allowing the 75-tonne machine to be pushed clear and prepared for lifting.
"This milestone brings us another step closer to delivering one of the state's most significant water security projects which will help future-proof the region's water supply," Minister for Water Rose Jackson said.
"As our climate changes, we need to invest in infrastructure that helps communities prepare for longer, more intense droughts while securing essential services for future generations."
The next stage of works will involve the installation of mechanical and electrical equipment and continuing works to connect the seawater intake structure to the treatment plant.
Once complete, the new plant will allow seawater to be drawn from the ocean for treatment, providing a dependable source of drinking water that can withstand future droughts and a changing climate.
"This project represents a once-in-a-generation investment in the Hunter's future, strengthening water security as the region continues to grow," Minister for the Hunter Yasmin Catley said.
"The Hunter has always been a place that builds big things, and this project is another example of the incredible engineering capability we have right here in our own backyard.
"This desalination plant is a game changer for our region. It gives families confidence that we have a reliable water supply as our region continues to grow."
The plant will be capable of producing up to 30 million litres of drinking water a day, enough to meet about 15 per cent of the region's average daily demand, helping to support water security for future generations.
The cost of the plant had more than doubled from an original quote of around $250 million.
The plant, which is expected to be operational in 2028, will add about an extra $90 to an annual residential water bill.
