Prime Minister John Key donned a hard hat and hi-vis vest on Friday as he toured the depths of the first of the twin Waterview Connection tunnels.
Key was taken almost 900 metres into the southern end of the tunnel which will eventually link State Highways 16 and 20 between Owairaka and Waterview.
"It's magnificent," Key says.
"It will obviously improve the congestion in Auckland."
The $1.4 billion project is the largest roading project ever undertaken in New Zealand and will complete Auckland's western ring route.
It includes construction of 4.8 kilometres of a six-lane motorway, half of which will be underground in Australasia's largest road tunnel.
Ongoing works at Lincoln Rd interchange, Te Atatu Rd interchange and the causeway on the northwestern motorway are also part of the western ring route.
Alice, the boring machine, began her journey in November 2013 to construct the tunnel for southbound traffic.
So far she has travelled 870 metres and has installed 435 of the 2400 concrete rings which creates the tunnel lining.
Waterview Alliance construction director Stefan Hanke says the project is making good progress.
"We expect to break through to the northern end in mid-September," he says.
"We expect that the tunnel boring machine will need to be replaced at some stage but it's nothing unusual. It's progress."
The western ring route is one of the Government's seven roads of national significance, and once completed it will be a 47km-long motorway between Manukau in the south and Albany on the North Shore, creating an alternative to SH1 and the harbour bridge.
The tunnels are due to open in early 2017.
Changes have been made to a section of the Great North Rd interchange where three lanes have become two.
The T2 lane on the eastbound on-ramp to the northwestern motorway is closed.
The lane closure is part of the New Zealand Transport Agency's Causeway Upgrade Project.
It will allow the on-ramp to be re-aligned with interchange ramps being constructed for the adjoining Waterview tunnel project.
- Western Leader
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