BLUE SKY THINKING: Richard Burrell on farmland north of Newlands which he suggests would make a better site for Wellington Airport.

A proposal to relocate Wellington Airport to a site on the hills north of Newlands is worth investigating, Greater Wellington Regional Council chairwoman Fran Wilde says.

The relocation, which has been labelled an "exciting" idea by Transport Minister Gerry Brownlee, has been proposed by Wellington property investor Richard Burrell, who said a completely new airport with a longer runway would have major economic advantages for the region.

It would take a lot of pressure off Wellington City's roading network and do away with the need for expensive roadworks, including a second Mt Victoria tunnel and more than $300 million that is needed to extend the current airport's runway.

Mr Burrell said surveyors and engineers had assessed a proposal to put an airport with a 2.4 kilometre runway - able to handle long-haul flights - on farmland at Hunters Hill, between Newlands and Grenada North.

The costings for a new 120ha airport came to about $750 million, far less than the estimated $1.1 billion needed to improve road links to Wellington Airport and to extend the runway.

If the current Wellington Airport was closed, the land could be sold off for housing and the net effect would be that Wellington would get a better airport with an all-up capital saving of around $500m, Mr Burrell said.

His plans were presented to Wellington City Council just before Christmas but Wellington Mayor Celia Wade-Brown was reluctant to be drawn on it.

Her only comment, conveyed by her spokesman, was "our immediate focus is on getting direct long haul flights from Asia as emphasised in our eight big ideas programme".

Ms Wilde said if it saved money it would be worth investigating - "You wouldn't want to close the door on any option."

Mr Brownlee gave his qualified support. "It's very exciting that someone has had an idea for a new airport, especially as when the private sector comes up with plans of this nature they tend to be fully funded.

However, "the Government has no intention of helping fund a new airport on the hills above Newlands".

Wellington Employers' Chamber of Commerce chief executive Raewyn Bleakley said the chamber was always interested in ideas that could boost the Wellington economy.

"But we would need to hear from aviation and construction experts, along with other feasibility studies and a robust business plan, before we would see this as a real or viable option."

Aviation New Zealand chief executive Ed Sims said a new airport development would be hugely challenging and there could be operational problems.

The altitude would be more prone to being clouded in, the winds would be stronger and gustier and the height of Mt Kaukau, just a few kilometres to the south, could be a problem.

Wellington Airport was well located for aircraft operations and close to the city and he doubted there would be commercial advantages. Mr Sims was also sceptical of estimates suggesting it would save $500m - "I'd be guessing it would be a zero sum game."