The route chosen for a motorway through Mt Albert is a mixture of tunnels and a surface road, Transport Minister Steven Joyce said today.
He said it would cost $1.4 billion, about half the price of the previous Labour government's plan for a twin tunnel.
"The proposed route includes building the motorway under Great North Road and in a tunnel under New North Road and under Avondale Heights," he said in a statement.
"The resulting underground sections represent around 60 per cent of the road's length."
South of New North Road the motorway runs through the Alan Wood Reserve corridor to the west of Hendon Avenue.
Mr Joyce said Waterview Primary School will not be affected any more than it would have been under Labour's tunnel proposal.
"This is a cost-effective option but it's still important to note that this will be New Zealand's most expensive roading project every by a considerable margin," he said.
"There were no easy options here but I believe this proposal will go a long way towards easing the concerns of many, while being cost-effective for New Zealand."
The motorway, known as the Waterview connection, will complete Auckland's Western Ring Route.
It has become a major issue in the Mt Albert by-election, which takes place on June 13.
Details of the new route were being released in Auckland this afternoon by the Transport Agency, which chose it from three options given to it by the Government.
New Zealand Transport Authority board chairman Brian Roche says the route was one of three considered and could be completed by 2015.
Mr Roche says the option selected could begin as soon as 2011.
"We've chosen a route option which we can afford now and which can be completed on time. We believe it provides the best balance between the need to complete the western ring route in an affordable way as soon as possible with the needs of the communities the road will pass through," Mr Roche said.
He said while completing the western ring route was crucial for the region's economic development, at a local level there was no easy way to achieve it and all options affected communities one way or another.
Yesterday Mr Joyce said officials had found that the final motorway link needed for the 48km western ring route could be built for between $820 million and $1.17 billion by scaling back the project so it could be paid for from the national land transport fund of fuel taxes and motor licence fees.
That would avoid spending $550 million on debt-financing, which would be needed for borrowing outside the fund to build the tunnels.
A further $240 million will be spent on widening and raising the adjoining Northwestern Motorway's sinking causeway to cope with extra traffic between Waterview and the Rosebank Peninsula.
- with NZ HERALD STAFF