For the third time Watercare’s micro TBM Domenica has broken through the Central Interceptor project in New Zealand’s largest city.
Following excavation of 1,212m from Blockhouse Bay, the TBM appeared at Avondale which is part of the first of two branch sewers for Auckland’s new wastewater system. Meanwhile it is the longest drive of the branch sewer project.
According to Central Interceptor executive program director Shayne Cunis: "The breakthrough was achieved ahead of schedule. We are incredibly proud of the efforts of the Ghella Abergeldie JV tunneling teams who have achieved this milestone more than a month ahead of schedule. They are a tight team with good skills and a bucketload of experience."
Cunis also added: "I’d also like to pay tribute to our designers, who modified the original plans so that we did away with the need for a shaft at Whitney St. This has saved residents considerable disruption, and reduced the cost and carbon footprint of the overall project."
Starting its journey in July 2021, the micro TBM travelled up to 25m and its daily capacity in laying up the pipe rings with 2.1m diameter was eight.
In order to refurbishing the cutterhead before she completes the final 330m early next year, Domenica is currently going to be removed from the tunnel.
August of next year is the scheduled date for beginning work on the second branch sewer, running from a site next to Mount Albert Memorial to Rawalpindi Reserve.
The branch sewers will link to the main 14.7km Central Interceptor tunnel, which is currently being laid underneath Manukau Harbour – the first time tunneling has taken place under a major New Zealand harbor.
Being considered as the largest wastewater project in New Zealand’s history, the Central Interceptor will store 226,000m3 of wastewater, control the flows into treatment plants and reduce the number of wastewater overflows.