The $8 million dollar project is expected to be completed in late November with some minor delays due to the wet weather.

Member for Bathurst Paul Toole announced the funding on Monday, August 17.

He said motorists would notice heavy machinery on site doing excavation work to rebuild the roadway.

"Earthworks and culverts are progressing well and the asphalt contract has been awarded," he said.

Mr Toole said the section of the Great Western Highway was a key route for residents, visitors and the freight industry alike, connecting the centres of Lithgow and Bathurst.

The highway upgrade will involve rebuilding the road, improving drainage and widening the centreline and shoulders.

"The widened shoulders and widened centreline will improve safety by allowing room for vehicles to recover should they leave the roadway," Mr Toole said.

"Road resurfacing will improve journey times and trip planning by providing a more reliable stretch of road."

The road works follow the recent completion of a $2.1 million upgrade at the nearby intersection of the Great Western Highway and Range Road.

"The combined aim of these safety improvements is to ensure those who set off on a journey return home safely," Mr Toole said.

Work will be carried out between 7am and 6pm from Monday to Friday and 8am to 1pm on Saturdays.

A reduced speed limit of 40 kilometres per hour and traffic controls will be in place for the safety of road users and workers.

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