"It will go through a very robust planning process. All the checks and balances will be gone through," councillor John Douglas said.
The 136km road link would connect the West Coast and the Milford Sound-Te Anau road via the Hollyford Valley. An estimated 98km of new road would be constructed through wilderness and the Fiordland National Park.
The highway's main backer, former Westland mayor and now chairman of Haast Hollyford Highway Ltd, Durham Havill, says he has overseas investors in the wings and construction costs estimated at $250m-plus would be recovered by user toll charges over 30 years. That would mean no financial input was required from national or local public funders.
He welcomed the council decision yesterday as "wonderful news".
"It means that the West Coast and Southland can now move united to make this road a reality. It will need Government support, but the people have spoken very loudly," Mr Havill said in a statement.
Opponents said this morning they were not worried by the latest development.
Mr Wilson said Federated Mountain Clubs, with 20,000 members, included engineers who had looked at the practicalities of the road a few years ago, and they concluded the true cost would be closer to $2 billion.
"There's a huge difference in cost. Our position has not changed (and) the road is uneconomic."
He said the club supported putting the idea under proper economic and environmental scrutiny, because it believed it failed both tests.
"One of the good things (from yesterday) is that it's getting put through an official process -- it won't meet the tests."
Forest and Bird advocacy manager Kevin Hackwell, on behalf of 90,000 members, also poured cold water on the economics of the road.
Even doubling the number of tourists it would still not make any sense, Mr Hackwell said.
"The reason I'm not losing any sleep is it doesn't make much economic sense, whatsoever."
That was apart from the "clearly huge environmental issues", he said.
When opened to serious inspection, it would show the road would never work -- something former Transport Minister Gerry Brownlee realised in 2010, after advice from the Economic Development Ministry and the Tourism Industry, Mr Hackwell said. Mr Brownlee said at the time the Government had no plans to advance it.
Discussions had stalled until earlier this month, when the current Transport Minister Simon Bridges said in a letter that while a private road was "theoretically possible", complex conservation and legal issues were expected, and the Government had no plans to support the project unless it passed through standard land transport planning processes.
Councillor Ebel Kremer, a former West Coast District Health Board manager who now represents the Te Anau area, yesterday supported sending the proposal to the regional land transport committee, saying the Southland District Council had been giving the public "mixed signals".
"It is good to see we have a pathway to go forward ... and this council cannot be seen to be holding the process up."
Council chief executive Steve Ruru said the next step was for the Southland council to convene a meeting with the Westland District Council, Haast-Heritage Highway Ltd and the NZ Transport Agency.
- Greymouth Star, additional reporting Otago Daily Times
