In a significant milestone, the TBM Hiwa-i-te-Rangi, nearly 200 meters in length, has successfully breached into a shaft at a depth of 47 meters below ground. This achievement took place at the Lyon Avenue site in Mt Albert, marking progress within the Watercare Services Limited’s Central Interceptor project. The journey spanned just over 11 kilometers from the shaft at Haverstock Road in Sandringham to Pt Erin in Herne Bay, where the 16.2-kilometer-long tunnel is being constructed. The next phase will see the TBM heading towards Western Springs later this year, having covered a distance of 2450 meters. Hiwa-i-te-Rangi is one of three TBMs actively involved in the Central Interceptor project in Auckland.  

On April 27th, 2024, the micro-TBM Domenica, with a diameter of 2.8 meters, successfully breached the concrete shaft wall at the Norgrove Ave site in Mt Albert, marking the completion of the second of two link sewers. Domenica, initially launched in June 2021 by the construction Ghella Abergeldie JV, has accomplished over 4 kilometers of tunnelling.  

Link Sewer B, exceeding 1 kilometer in length, intersects the main Central Interceptor tunnel at the Mt Albert War Memorial site. Together with Link Sewer C, which connects to the main tunnel at May Rd, these link sewers will gather combined wastewater and stormwater flows from West Auckland, diverting them to the Māngere Wastewater Treatment Plant for processing, thereby preventing discharge into streams and beaches during heavy rainfall.  

Domenica is currently being extracted from the shaft, along with pipe-jacking equipment and other necessary services. Teams of welders are engaged in thermal welding on joints in the tunnel’s plastic liner, a crucial step to safeguard against the corrosive impact of wastewater, ensuring a lifespan of up to 100 years.  

Victoria, a micro-tunnelling TBM measuring 12 meters in length, is the third TBM involved in the Central Interceptor project. It is currently linking the main tunnel to the local wastewater network in Keith Hay Park, Mt Roskill.  

A portion of the Central Interceptor tunnel, along with the link sewers, is set to become operational before the year's end. The project is scheduled for completion in 2026.   

For further information click here and nz/18 for tunnelbuilder archive. Visit  https://www.watercare.co.nz/   and https://www.gajv.co.nz/. 15/24.