KEY POINTS:
Auckland's rail development boom will hit city traffic today as construction crews start replacing road bridges between Grafton and Newmarket to make room for electrified lines below.
The work begins despite the National Party's refusal to clarify how it would fund Auckland's $1 billion electrification project.
It has voted against legislation by which the Government is poised to approve a regional road-fuel tax for that and other transport infrastructure.
Government agency Ontrack is recommending motorists plan alternative routes for the next year - or even longer - while it rebuilds the two bridges, halfway along Khyber Pass Rd and in Park Rd, near Auckland City Hospital.
Although two-way traffic will still be able to use them for now, lanes available to drivers will be reduced on what are key routes between Newmarket and central Auckland.
Ontrack says it has been in close consultation with the Auckland City Council and emergency services but is warning motorists - particularly those travelling to the hospital - to allow extra trip times or to find other routes.
The replacement bridges are needed to allow enough room below for the western railway line to be duplicated and electrified as part of a $70 million redevelopment of Newmarket junction through to Boston Rd in Mt Eden.
A new railway station will also be built between the bridges to offer easier access to the hospital and Auckland Domain than the existing Boston Rd stop under the Southern Motorway.
Despite the importance of Khyber Pass and Park Rds, Ontrack spokeswoman Jenni Austin said engineers had concluded after traffic modelling that overall disruption would be minimised by replacing both bridges simultaneously, between now and late next year.
She said traffic had already declined in Park Rd since the city council began widening it several months ago as part of the $43 million Central Connector busway project between Britomart and Newmarket, evidence that many drivers would have found less disruptive routes.
Park Rd, which in normal circumstances carries about 17,000 vehicles a day, is expected to become even quieter when the council closes Grafton Bridge on October 25 for 14 months of structural strengthening.
More than 30,000 vehicles use Khyber Pass Rd a day but drivers unable to find acceptable alternative routes will be confined to just one eastbound lane, to make room for two lanes of city-bound traffic.
All components of the Newmarket rail upgrade are being "future-proofed" for the proposed billion-dollar electrification project, on which the Government is about to wave the green flag by approving an Auckland Regional Council application for a special road-fuel tax to pay for it.
That could range from 2c a litre from next July to 10c in 2011 if the Government decides to match the council's application for a scale of 1c to 5c, to pay the state's half-share of electrification while also raising extra money for selected roading projects.
Finance Minister Michael Cullen said last week that the Government viewed Auckland's electrification projects as a "lock-down certainty" but National is refusing to say whether it would abolish new regional fuel tax legislation.
Although party transport spokesman Maurice Williamson has said National would honour commitments to electrify the three railway lines from Papakura and Swanson to Britomart, he favours alternative funding devices such as public infrastructure bonds.
He has declined to respond to a challenge by Transport Minister Annette King to "come clean" on how National will fund the electrification of Auckland rail.
"The suspicion is growing daily that National, given its attitude to rail generally, won't back this project at all," Ms King said.
"Although National has said it will honour commitments that have been made, the fact is they have failed to come up with any funding mechanisms of their own, so the commitment is a very hollow one indeed."
