Auckland Mayor John Banks wants a $1 billion-plus harbour tunnel starting at Mechanics Bay and coming up at Ngataringa Bay near Devonport.

He said yesterday that the new harbour crossing could link with the eastern corridor, which he is trying to build within five years as a toll road with private sector funding.

The eastern corridor toll road could cost drivers $5 for a return trip. The harbour crossing could also be paid for by tolls, Mr Banks said.


The toll on the eastern corridor could operate with pre-paid cards attached to windscreens.

"My proposal is that the third harbour crossing would link up with the eastern corridor somewhere around Mechanics Bay, go under the harbour, out under Devonport and exit at Ngataringa Bay to lock into the Northern Motorway," Mr Banks said.

That would give two circle roads around central Auckland - the eastern corridor and the western ring route via a new Upper Harbour Motorway - to take congestion off the Harbour Bridge, he said.

The harbour crossing is the second tunnel idea unveiled by Mr Banks. He promised voters at last year's election that he would investigate a road, rail and sewer tunnel beneath Hobson Bay to turn the bay into a marine reserve. No work has been commissioned on this project.

Transit has consultants working on a separate plan for a new harbour crossing, either a bridge or a tunnel, near the existing harbour bridge.

It is keen to secure a route and land by 2004. Construction would not start before 2010.

Mr Banks said the eastern corridor was the first step in a grand traffic plan that could eventually see the eastern corridor link with the North Shore.

Auckland and Manukau cities with Transit New Zealand have agreed to work together to complete the eastern corridor as soon as possible.

Auckland City is leading the project, which straddles the railway line from the Mt Wellington Highway, through the eastern suburbs, Purewa Creek and across Orakei Basin and Hobson Bay.

Virtually no work has been done on connecting the corridor at its city or southern ends, but it is known that it will threaten the Parnell Baths, Tamaki Drive and Judges Bay, and it could cut through large residential areas of Pakuranga.

Since Mr Banks declared that a $3.8 million renovation project for the Parnell Baths had been put on hold because they could be skittled to make way for the eastern corridor, more than 5000 people have signed a petition to save the baths.

The Government has promised to introduce legislation before the election this year to allow Auckland to build toll roads using private sector partnerships.