"Steady" Alice underway again at Waterview

The huge tunnel boring machine (TBM), Alice, is now well into her return journey to complete the second motorway tunnel for the NZ Transport Agency’s Waterview Connection project in Auckland.

Alice has excavated more than 630 metres of the second tunnel, which is just over a quarter of the way along her 2.4km-long southbound journey to Owairaka. She is 22m below ground and has passed under Great North Road, one of Auckland’s busiest arterial links.

“Alice is making very consistent and steady progress. Everything is on track for her planned breakthrough at Owairaka in mid-spring,” says the Transport Agency’s Highways manager Brett Gliddon.

Tunnelling resumed after a complex operation to turn Alice, the world’s 10th largest TBM, around. The front section or cutter head of the TBM was turned first to excavate the first 250m of the second tunnel and provide room for the rest of the TBM and other facilities.

“Worldwide, very few TBM’s are turned to complete a second run underground and the project’s extraordinary innovation to achieve this manoeuvre with just millimetres to spare at times is now fully complete. All the support facilities for Alice are in place and fully functioning,” Mr Gliddon says.

Alice broke through into daylight at the end of last September after excavating the first of the two three-lane tunnels that are part of New Zealand’s biggest and most ambitious road transport project.

Alice’s work is one part of this year’s busy works programme to complete both tunnels

• Temporary bridges have been built linking the tunnels’ northern portals to speed up supplies of concrete tunnel segments to the TBM
• Backfilling is underway to build the motorway lanes and install the concrete culvert – the tunnel within a tunnel – to carry electronic and electrical services is underway in the second tunnel.
• Installing mechanical and electrical equipment in the first tunnel is starting
• Work is also beginning on the excavation of 17 cross passages that will connect the two tunnels
• The ‘hole’ above the northern portals – the Northern Approach Trench – is being covered to accommodate new local road layouts above ground

“Together with building the Great North Road Interchange and widening the Southwestern Motorway south of the tunnels, the Waterview Connection is a very busy place as we work towards the project’s opening in early 2017,” Mr Gliddon says.

The tunnels and interchange will link the Northwestern and Southwestern Motorways to complete the Western Ring Route.

The Western Ring Route will be a 47-kilometre-long motorway between Albany on the North Shore and Manukau in the south. It will deliver several benefits for Auckland and the city’s regional neighbours. It will give drivers a second motorway choice to the Southern and Northern Motorways (SH1) through central Auckland, improve access to important commercial and residential destinations, reduce traffic on local roads, and provide better links for public transport and for people who walk and cycle.

The Waterview Connection 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.

Key links:-

www.facebook.com.alicetbm(external link)

http://www.youtube.com/wcnow(external link)

http://www.nzta.govt.nz/projects/waterviewconnection(external link)