Highway projections challenged
Traffic flow projections showing the proposed Petone to Grenada link road should extend to Transmission Gully are dodgy, Takapu Valley residents told Wellington regional councillors last week.
Bruce Flett told the council NZ Transport Agency’s costings were poor and the road would cause ‘‘massive congestion’’ where it met State Highway 1, whether south of Porirua or at Pauatahanui.
Many councillors agreed and the council is to submit a proposal about the road that includes many of his concerns.
Flett was speaking in the public participation section of the council’s meeting on May 21.
The agency’s stated objectives for the road – safety, efficiency, heavy commercial vehicle compatibility, supporting growth, network resilience and minimising adverse effects – were vague and could equally apply to almost any road project, he said.
‘‘You could build a tunnel under Rimutaka Hill and it would meet these objectives.’’
Without good objectives, chances of success were very poor, he said.
Furthermore, the agency’s traffic flow projection from 42,000 vehicles each day past Tawa College in 2001 to 62,000 by 2026 had shown no sign of eventuating.
‘‘ We have exactly the same growth figures being used despite the fact that there has been no growth,’’ he said.
‘‘ Our contention is that the modelling is suspect, to say the least.’’
Councillor Paul Swain, who was once the Minister of Transport, said the figures threw all the modelling into doubt.
The spending was self-defeating because the road would compete with Wellington’s recently upgraded rail network. Both were funded by the agency.
‘‘It is difficult to understand why NZ Transport Agency, the major funder of the rail upgrade, has come up with something like this,’’ he said.
Nigel Wilson described the plans to extend the road as ‘‘ NZ Transport Agency nuttiness’’.
‘‘It seems to me that agency thinking is very siloed and leads to these incongruous positions all the time,’’ he said.
Council chairwoman Fran Wilde told Flett the regional council’s submission on the route would reflect most of his concerns.
The council’s submission rejected both possible extensions and supported an alignment for the Petone to Grenada section which avoided Belmont Regional Park and Korokoro Valley.
It also supported a new inter- change at Petone and called for walking and cycling provisions on the road, major improvements to Hayward’s Hill road and for the the agency to work with Hutt City Council to develop a cross-valley link to make the best of the new highway. Traffic flows past Tawa College on State Highway 1 have increased significantly since 2001.
NZ Transport Agency figures show there were just under 38,000 vehicles each day in 2001 and the latest figure is 42,000, an increase of 10.5 per cent.
The agency’s
Wellington highways manager, Rod James, said traffic levels were expected to rise more by 2026 because the new road would change travel patterns by creating a direct link to the Hutt Valley.
It provided a real opportunity to provide shorter, safer journeys for thousands of people daily, will bring the region closer together, foster economic growth and provide the confidence of an alternative route in the event of major crashes or earthquakes.
The agency understood there were concerns and no decisions had been made, particularly for dealing with forecast congestion north of Grenada.
The two options that Bruce Flett and the regional council objected to, C and D, had been designed to prevent congestion by providing additional capacity to accommodate the projected increased traffic travelling between Transmission Gully and the proposed link road.
Although Flett believed the project’s objectives were vague and generic, the 1400 submissions from the public showed widespread acceptance of them, James said. They related to safety, resilience in the event of major disruption, economic growth and environmental effects. The project cost estimate between $250m and $ 270m was standard for large projects, he said.