17 October 2014

Sheep to help Alice’s slippery slide at Waterview

Some of New Zealand’s 30 million or so sheep are set to play a critical role in the next stage of the country’s largest roading project, the NZ Transport Agency’s $1.4b Waterview Connection in Auckland.

The sheep are providing 200 litres of lanolin – the wax extracted from their wool – that will be used to help slide the project’s giant tunnel boring machine into position so that it can start excavating the second of the twin motorway tunnels.

“Shifting Alice is probably one of the most technically challenging tasks of the whole Waterview project,” says the Transport Agency’s Highway Manager Brett Gliddon. “It’s not unusual internationally to turn a tunnel boring machine, but what makes this operation extraordinary is the sheer size of Alice – she is the 10th largest of her kind in the world – and the very tight space the project team has to manoeuver and turn her.

“That’s where the lanolin from our sheep plays its part. It has the right qualities to be added to the cocktail of grease necessary to help slide Alice around in such a constrained area.”

Alice completed the first leg of her underground journey – travelling 2.4km north from Owairaka to Waterview – and broke through into daylight on 29 September.

Alliance executives and workers today (17 October) officially celebrated last month’s breakthrough and the half-way stage of the project at a ceremony at Waterview. Their guests included Government Minister Nikki Kaye, local government leaders, elders from Ngati Whatua, the kapa haka group from nearby Waterview Primary School, other neighbours of the project, and Branden Hall the Auckland schoolboy who won the completion to name Alice.

Alice is almost 88 metres long and too big to be turned in one piece. She is now being separated – similar to a train with trailing carriages – and brought out of the completed tunnel one big piece at a time. The first section – the 2400 tonne shield that includes the cutting head – is now resting on a steel cradle waiting to be turned and moved across 20 metres.

After being turned, the shield will be re-launched southwards in late November to bore the first 300m of the second tunnel. That distance will provide room for the other sections of the TBM to be re-connected with the front shield. Tunnelling will fully resume next March and the final breakthrough, at Owairaka, is expected by September.

“A busy five months ahead, but the ingenuity and innovation involved with the complex turnaround is another example of why the project’s attracting attention here and overseas,” Mr Gliddon says.

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.

The Waterview Connection is one of six related projects either finished or underway to complete the Western Ring Route and link Auckland’s Northwestern and Southwestern Motorways (State Highways16 and 20).

The Western Ring Route is one of the Government’s seven Roads of National Significance. The 47 kilometre-long motorway will run between Manukau in the south, the upper end of the Waitemata Harbour, and Albany on the North Shore, and ease pressure on the SH1 motorway through the central city area.

The Western Ring Route will improve transport connections within Auckland, particularly with the international airport, and with the city’s regional neighbours in Northland and Waikato/Bay of Plenty.

The Waterview tunnels and the adjacent motorway-to-motorway interchange to connect SH16 and SH20 are planned to open in early 2017.

For more project information contact: nzta.govt.nz/projects/waterviewconnection
Visit the Well-Connected Alliance’s Facebook page for updates on Alice: facebook.com/AliceTBM.

ENDS

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