Alice, the huge tunnel boring machine for the Waterview Connection project in Auckland, has constructed her first quarter-kilometre of tunnel.
The NZ Transport Agency’s Auckland Highways Manager, Tommy Parker, says that after a cautious start last year, Alice has just passed the 250m mark on her south-north journey from Owairaka to Waterview. She has 2,150m to go to complete her first run.
On the single best day of tunnelling to date, Alice excavated 22 metres of tunnel – a shade longer than the length of a cricket pitch - and installed the giant concrete rings that form the tunnel’s wall.
“Alice went through a careful probation period while the team operating her familiarised itself with the systems and processes involved in a complex project of this size,” says Mr Parker. “After that cautious start, she has come up to speed and is now demonstrating what she’s capable of.”
The TBM will build twin 2.4km-long tunnels, both 13.1m in diameter, over the next two years to connect Auckland’s Southwestern (SH20) and Northwestern (SH16) motorways as part of the city’s Western Ring Route, one of the Government’s flagship Roads Of National Significance (RONS). Each tunnel will carry three lanes of motorway traffic.
The TBM is due to complete construction at the end of 2015 and the tunnels open to traffic in early 2017.
Mr Parker says Alice has not encountered any show-stopping issues on her journey so far. She is currently around 25 metres below the surface. At her deepest - around the middle of the tunnel – Alice will be 40m below the surface.
Mr Parker says the Transport Agency is confident that Alice will reach Waterview in late September as scheduled, completing the project’s southbound tunnel. At Waterview, she will be turned around and then launched southward to build the second (northbound) tunnel.
When the TBM reaches the 500m mark next month, it will take a break of approximately three weeks so that a special gantry can be assembled inside the completed section of tunnel. The gantry will be used to put in place a culvert that will run below the level of the motorway and carry the mechanical and electrical services needed to operate the tunnel.
Mr Parker says the culvert installation 200m behind the TBM will allow work to start on the first stage of motorway construction. This will, in turn, provide access for the construction of the first of the 16 cross-passages connecting the twin tunnels, and the later installation of tunnel lighting and ventilation systems.
“Co-ordinating all these different work streams demonstrates the complexity of the project. The more completion work we can do behind the TBM, the quicker we can open the tunnels to traffic and the quicker Auckland and our regional neighbours will begin to experience the benefits the Western Ring Route will bring.”
The Waterview Connection project is New Zealand’s biggest-ever road project. It will deliver a 5km, six-lane motorway connection, half of which will be underground. As well as completing the Western Ring Route, the Waterview Connection will provide a direct motorway link between the CBD and Auckland International Airport.
Work started in early 2012, and 3 million man hours had been completed by the end of January. The project currently has a workforce of 660.
The project is being delivered by the Well-Connected Alliance which includes the Transport Agency, Fletcher Construction, McConnell Dowell, Parsons Brinckerhoff, Beca Infrastructure, Tonkin & Taylor and Japanese construction company Obayashi Corporation. Sub-alliance partners are Auckland-based Wilson Tunnelling and Spanish tunnel controls specialists SICE.
Four other related projects on the Northwestern Motorway (SH16) to complete the Western Ring Route RONS – upgrades of the Lincoln Road and Te Atatu Road interchanges, the Causeway Upgrade Project and widening the motorway between the St Lukes and Great North Road interchanges – are underway or about to start construction.
For more information please contact:
Auckland/Northland Media Manager
NZ Transport Agency
T: 09 928 8720
M: 027 213 7616
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