Published 24/11/2022
Tunnel borer receives iwi blessing
Local iwi has welcomed the arrival of Te Rū Tiokaoka in Wellington as the next phase of the Barber Grove - Seaview wastewater pipe renewal project gets underway.
Te Rū Tiokaoka is a state-of-the-art micro tunnel boring machine (MTBM) destined to travel 600 metres underground drilling a new duplication pipe along Randwick Road to the Seaview roundabout.
It has operational and environmental benefits. There is no open trenching, so less disruption for road users, enabling two lanes of traffic along the entire length of Randwick Road during the underground drilling.
Te Rū Tiokaoka is uniquely resourceful and will only excavate the required earth to install the pipe while bypassing other underground pipes and cables without needing to cut or move them. and the production and transporting of new materials on-site compared to conventional trenching This minimises the volume of waste going to landfill, reducing carbon emissions.
Kaanihi Butler Hare, from Te Āti Awa, said the arrival of the MTBM was eagerly anticipated after the local Waiwhetu Marae had been approached to name the tunnel borer and provide Kaitiakitanga for the project.
“We chose the name Te Rū Tiokaoka because it relates to Rūamoko the ‘God of earthquakes’ and the journey it will make moving through Papatūānuku [land], tunnelling residue and soil aside.
“This mahi provides local iwi a peace of mind, we want to protect the mana and spiritual being of the Waiwhetu and Awamutu streams.
“Mana whenua acknowledges the willingness of Wellington Water and contractor McConnell Dowell to engage with us at an early stage and allow for Karakia and Kawa [incantations of protection] to be placed on and around the whenua that the project is taking place. We have in return provided a ‘Korowai Atawhai’ [a cloak of protection] and goodwill towards the mahi.”
Wellington Water project lead Linda Fairbrother says, “We are really excited about using Te Rū Tiokaoka. It’s the first time Wellington Water has used this technology on a project, and it is a milestone moment to have it on-site, ready to start drilling.
“This work is critical to building the resilience of the Hutt Valley’s wastewater network. The current wastewater pipe is over 60 years old, so it is nearing the end of its life making it vulnerable to failure and damage from an earthquake.”
Te Rū Tiokauka was manufactured in Germany and packs a lot of complex engineering into its 1.3m diameter body says McConnell Dowell project manager Jake Braithwaite; “This will be the fourth tunnel she has bored for McConnell Dowell, having completed a marine outfall requiring a barge to collect her 400m out to sea, and setting a world record for a 2km continuous tunnel drive in Auckland.
Fitting the project brief
- It is 3 metres long x 1.3m high (diameter)
- It weighs: 7.8 tonnes it is about the same weight as 11 cows
- It moves at 10 metres per day
- It will go 9 metres deep - this means the pipe will be positioned in a more resilient ground layer and is more likely to be protected from earthquakes.