More Aucklanders are leaving their cars at home for the commute to work as high petrol prices bite.
New figures show almost 900 fewer cars a week travelled over the Auckland Harbour Bridge this year compared with last year.
The drop corresponds with a fall in petrol sales in the city and an increase in public transport patronage.
NZTA figures show 1,684,601 cars crossed the bridge in the year to December, 44,545 fewer than last year.
Figures provided by New Zealand-owned petrol retailer Gull from local authority levies on petrol sales in the Auckland region showed 19 million fewer litres of petrol were sold in the year to June - a two per cent drop on the previous year.
And Auckland Transport Authority figures show there were 68,590,762 passenger trips on buses, trains and ferries for the 12 months to October 2011 - an increase of 6,033,457 or a 9.6 per cent rise for the year.
The details prompted one lobby group to question investment in motorways.
"Why are we investing so much in motorways when there's no growth in state highway traffic at the moment anyway but there's record growth in public transport patronage to the point where we won't have enough capacity on our rail network shortly to get into Britomart," Campaign for Better Transport spokesman Cameron Pitches said.
Pitches said improvements to the motorway network such as the $340 million Victoria Park Tunnel project could see more cars return to the roads, though he was sceptical of the forecast 20 minute improvement in travel times.
AA spokesman Simon Lambourne said the drop in bridge traffic was small, compared to the amount that crossed it every day.
While petrol prices were high, the drop could also be put down in part to the creation of alternative routes and upgrades such as that to State Highway 18, Hobsonville.
"So long term that's a welcome trend because of course it frees up the infrastructure on State Highway 1 and particularly on the harbour bridge where there is considerable congestion in the morning and afternoon peaks."
AA members preferred buses as the means of public transport, provided the network could be improved, though it should be funded by central and local government, he said.
"We do have transport problems here in Auckland and the solution for the future has to be investment both in public transport and the roading network. To focus on one and not the other is a recipe for disaster in the future."
Mayor Len Brown is a major public transport supporter and continues to advocate for funding for improvements such as an inner-city rail loop.
A second harbour crossing is also being debated, but all parties are considering cost-benefit analysis for the project. A second bridge or a tunnel is being proposed, with public transport and cycle options included.
- Auckland Now
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