The $2.03 billion upgrade was announced in the federal government's budget in May as part of a 10-year Infrastructure Investment Program, and will begin between Katoomba and Blackheath and between Little Hartley and Lithgow.

Mr Gee, also the Minster for Decentralisation and Regional Education, said the upgrades will help alleviate increasing congestion issues and are 'critical to securing the continued growth and prosperity of the Central West region.

He highlighted the COVID-19 pandemic as one major factor in that increasing congestion, with an increasing number of people moving or travelling west of the Blue Mountains as a result.

"Since the onset of the pandemic there has been a real awakening by people in the city as to what lies over the Great Dividing Range, or sandstone curtain as we like to call it," he said.

"This movement from the city is bigger than the gold rush and it looks set to continue as Sydney expands westward and the new Western Sydney International Airport takes shape.

"According to the latest data from the Australia Bureau of Statistics a net 43,000 Australians moved to the regions in 2020 - the year prior the net figure was nearly 19,000, so it's more than doubled.

"When gold was discovered at Ophir near Orange in 1851, tall ships in Sydney Harbour were abandoned for the new gold fields in search of fortune and a better life. We haven't seen migration inland like this since those early times and it's been a pandemic-driven decentralisation story.

"With more and more people crossing the mountains, congestion will only worsen."

Mr Gee pointed to the Easter long weekend as an example of congestion, although the Bells Line of Road's closure due to flood damage also played a large role in exacerbating that highway traffic.

"Over the Easter holidays it took both my daughters over nine hours to get to Orange from Sydney, many from our region have recent horror stories like this," he said.

"Easing congestion, making this road safer and reducing travel times is why the Australian Government has invested in the East and West sections, between Katoomba and Lithgow, which will be the first to kick off with designs to be released to the community in coming weeks. This means motorists will benefit sooner.

"This builds on the Medlow Bath safety upgrade [at Bellevue Crescent and Foy Avenue] on the Great Western Highway which is now complete.

A wider, safer highway through Medlow Bath has now been delivered through the Australian Government's Road Safety Program while the major multi-billion dollar project gets cracking."

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