Sue Kedley

Wellington, June 25 NZPA - The controversial Transmission Gully motorway proposal north of Wellington was labelled a "lemon" in Parliament today as potential pitfalls were pointed out.

Quoting from a Transport Ministry report released under the Official Information Act, Green Party MP Sue Kedgley said earthquake risk, steep gradient, potential traffic increases and cost made it a poor option.

The route would run inland from Wellington towards Levin and its cost has been put at over $1 billion. An alternative is to upgrade the current coastal route.

The report has put the gully proposal's benefit cost ratio (BCR) at a low 0.36 to 0.5.

Ms Kedgley asked whether Transport Minister Stephen Joyce would approve a proposal where the costs outweighed the benefits by up to a factor of three.

Mr Joyce admitted the BCR would be lower than one, but said it would be similar for a coastal upgrade option.

"It's clear there are no inexpensive options here because of the very rugged geography north of Wellington, which makes construction difficult."

He said BCRs were one of a range of factors taken into consideration when building roads, but could be boosted when wider economic benefits were realised.

In relation to the earthquake risk, he said there were also security issues with the coastal route, along with environmental concerns.

Ms Kedgley also pointed out a necessity for escape ramps on a particularly long and steep stretch on the gully plans, which could deter truckies, and the threat of train commuters flocking to cars as a result of a new motorway.

"I'm not necessarily convinced that increasing the use of one mode over another will cause further congestion," Mr Joyce said. "It may just mean that the particular mode is easier to use."

He said the Government would make decisions on the options before the end of the year.