Plans to duplicate the highway between Katoomba and Lithgow have been revealed and involve tunnels, bridges and no encroachment on the National Park.
Under the proposals released by the RMS last Thursday (November 7):
From Katoomba to Medlow Bath, there will be bridges between highpoints along the ridgeline.
At Medlow Bath, the existing corridor would be widened within the current property boundaries through the township with a 60km/h speed limit.
Options from Medlow Bath to Blackheath include widening the existing corridor or running along the western side of the rail line.
Blackheath remains a shaded area on the map with a number of options on the table. These include: widening the existing corridor; an outer bypass with bridges over Shipley Road, Centennial Pass and Porters Pass Track; a western bypass; or a long tunnel or short tunnel bypass (both beneath the town).
Options that run around the eastern side of the Blackheath village have been ruled out because of its potential impact on the World Heritage Areas of the Blue Mountains, and options running directly through the National Park have also been ruled out.
From Blackheath to Mount Victoria, the plans would widen the existing corridor and make changes to the Mount Boyce Heavy Vehicle Inspection Bay.
A tunnel bypass beneath Mt Victoria is planned between the village and the base of Victoria Pass.
From the bottom of the pass to South Bowenfels, the plans would include a four-lane divided road with a 100km/h speed limit.
The RMS notes: "We are still in the early stages of planning and design, and need your feedback in order to take forward the project. Further survey work, technical studies and environmental assessments are also needed to refine our understanding in developing the program."
It has invited feedback from the public and will conduct public consultation sessions from late November into December.
The mayor of Blue Mountains, Mark Greenhill, said the plan did not address the needs raised by Mountains residents.
"This looks to me like a recipe to dump more and bigger trucks on to the Great Western Highway, impacting every town from Lapstone to Katoomba.
"I am concerned about the environmental damage this will do, the impact on the world heritage area. I believe that it will make the situation worse for upper mountains towns as well."
The Blackheath Highway Action group fought a similar proposal 10 years ago. Its spokesman, Michael Paag, said it was a "gigantic waste of taxpayers' money.
"Here we go again. This proposal is shortsighted. The numbers don't stack up, the experts don't support it, the Natioinals don't support it and it won't solve the transport needs of the Central West.
"But it will forever damage the Blue Mountains and leave a legacy of frustration and missed opportunity.''