A highway upgrade at Blackheath may not be completed for a decade, according to the man running the project.
Alistair Lunn, director, western region for Transport for NSW (which RMS is now part of), also said more work would have to be done on the highway east of Katoomba before larger B doubles could drive on it.
In an interview with the Gazette, Mr Lunn said that parts of the highway, such as at Faulconbridge where there are virtually no shoulders, would have to be improved before the longer trucks would be allowed.
RMS documents, however, say that the upgrade is designed to carry B doubles to 26 metres and other trucks to 30 metres long.
The RMS last month released its options for duplicating the highway between Katoomba and Lithgow. They include a huge "strategic corridor" across Blackheath with options for a wide bypass over Centennial Glen, a bypass along Station Street, widening the highway through the centre of town or a tunnel/tunnels.
Mr Lunn said doing nothing was always an option "if it doesn't stack up economically".
He also said it will be "five, eight, 10 years before something is done in Blackheath".
The RMS had been criticised for releasing the options at this time of year. Mr Lunn said he thought early November gave people adequate time but conceded "we have been slaughtered for having dropped this little bomb at Christmas".
There have been more than 500 individual comments given as feedback, 60 per cent of which were about Blackheath and most opposing all of the plan, he said.
Of those who accepted that something will happen, the majority supported a tunnel, which would be the most expensive option.
Mr Lunn said upgrading Bells Line of Road would be problematic because it traverses the World Heritage area, had difficult topography and, at 60-70 kilometres, was much longer than Katoomba to Lithgow (34 kilometres).
There were also difficulties with rail.
"There's a real constraint between passenger use ... and freight. Rail is always part of the mix and we want to put more and more on rail but the rail solution is very congested."
He also admitted that mistakenly distributing leaflets to some Blackheath residents warning of potential property acquisition had been a "stuff up".
