Aucklanders have two options to address the city's transport funding gap: road tolls, or higher rates and fuel taxes.
That's the conclusion of a high-level report, released this afternoon, which gives Auckland Council and the Government a clear timetable for when new revenue sources will be needed to raise an extra $400 million for each of 30 years - $12 billion in total.
The money will be for projects such as the City Rail Link and new roads, including another Waitemata Harbour crossing.
But Transport Minister Gerry Brownlee immediately ruled out two options.
"We say no to regional fuel tax and no to tolls on existing roads,'' he told 3 News.
The report, by the Consensus Building Group (CBG), a 17-member think-tank appointed by Mayor Len Brown, concluded that unless Aucklanders were prepared to accept significantly higher rates increases and heavier congestion, introducing some form of congestion charge by 2021 would be required.
CBG chairman Stewart Milne said these decisions would need to be made by 2015.
"The group has also strongly recommended that the Government increase its funding for transport in Auckland and establish mechanisms that support an ongoing commitment to increased government funding.
"Recent commitments by the Government are the first step toward securing long-term financial support for improvements to Auckland's transport infrastructure."
Mr Brown said the report offered the clearest picture yet of the choices available for funding Auckland's transport future.
"Clearly road pricing is an option we must look at closely, along with our ongoing work to improve the transport options available to Aucklanders. As well as helping to fund new investment, road pricing offers a proven way of managing congestion and encouraging greater use of public transport."
Auckland Chamber of Commerce head Michael Barnett said for real progress to be made a comprehensive assessment and modelling of the two options needed to be undertaken and translated into firm proposals that Aucklanders and central Government could assess.
"All Aucklanders need to understand that if they are going to continue to use their car in the future, there will be an increased price to pay.
"Some of that increased price is driven by the relative inefficiency of the public transport system, which also needs to be addressed."
The Automobile Association, which is a member of the CBG, said one of its key concerns was that costs for improving the transport system were shared fairly.
"... We are pleased that the options being considered involve everyone contributing," motoring affairs general manager Mike Noon said.
"Road pricing is an option but the devil will be in the detail and further work and analysis is required to ensure the fairest and most effective approach."
The Employers and Manufacturers Association backed the CBG's findings.
Chief executive Kim Campbell said with such a wide spread disparity of views represented in the group, the agreement reached was "remarkable".
"By 2015 we need to decide how to raise this extra funding if Aucklanders are not to pay a whole lot more in other ways through traffic jams and delays in getting to work," he said.
"Our in-depth investigation agreed the preferred option for raising the extra funding should be through tolling the road network in some way, together with raised fuel taxes and including a substantial contribution from the government."
Campaign for Better Transport Cameron Pitches also endorsed the report, but warned that a consequence of any form or road pricing would be to shift more people onto public transport.
"We need to have that capacity in place first for road pricing to be effective," Mr Pitches said.