Cracks shut Great Western Highway's Convict Bridge for at least two weeks
Geotechnical assessments over the next two weeks should determine what is causing the cracks. (Supplied: Transport for NSW)
In short:
A key bridge along the Great Western Highway in the Blue Mountains will be shut for at least two weeks while geotechnical experts investigate cracks and movement.
The historic Convict Bridge at Victoria Pass was closed in both directions early on Monday morning when damage was detected at the site.
What's next?
Transport for New South Wales technicians will drill holes into the structure built in the 1830s to determine what is causing its instability.
A crucial bridge that links Sydney to the state's Central West on the Great Western Highway will be shut for at least a fortnight while specialists assess why it is moving and cracking.
Transport for New South Wales (TFNSW) closed the Convict Bridge in both directions on Victoria Pass in the Blue Mountains early on Monday morning, after instability was detected at the site.
All vehicles that ordinarily use the popular route are being redirected through Lithgow to the Bells Line of Road and Chifley Road.
TFNSW executive director of regional road maintenance Alistair Lunn said it remained unclear how long it would take to fix the bridge.
"We are working as quickly as we can to get an understanding of the failure, which will then lead us to be able to design a solution," he said.
"That monitoring will occur over a week or two, so that'll take a bit of time."
The damage along Convict Bridge has forced authorities to close it to traffic. (Supplied: Transport for NSW)
Mr Lunn said the failure was complicated and geotechnical assessors were working to identify what had gone wrong in the bridge's fill material.
"We're doing a series of drill holes into that fill and we're putting in technical instruments to measure bore water pressure, as well as to see what movement is still undertaking in that failure," he said.
The drilling will help determine if there are any holes in the fill material before technicians bore deeper to work out whether they need to resecure any infrastructure into the bedrock.
Mr Lunn encouraged people heading to the Central West this weekend for tourism or sporting events, including the NRL Panthers versus Sharks game in Bathurst, to consider other routes.
"We would encourage people to utilise where it's convenient the Golden Highway and other routes, such as down onto the Hume near Yass, to spread the load," he said.
"We are very conscious that to the people of the Central West … this is a vital link and we thank them for their patience."
The road winds through the steep Hartley Valley. (Supplied: David W Noble)
'Chaos' for residents
A Lithgow village group said the ongoing closure was causing "chaos" for its community at the bottom of Victoria Pass.
Farmer and Hartley District Progress Association president, Ramsay Moodie, said it was frustrating for residents trying to go about their daily lives.
"It's locally causing chaos, with people having enormous difficulties getting to work," he said.
"We've got one of our people that lives up in Mount Victoria. It's now taking them an hour and a half to get home when it normally takes 10 or 15 minutes."
He said businesses in the area that relied on the Great Western Highway's thoroughfare were struggling.
"One of them in particular is the Lolly Bug, just at the base of Victoria Pass … it really relies on its established reputation with passing traffic," he said.
"It's got good signage on the highway but when there's nobody on the highway, life gets pretty mean."
Meanwhile, Lithgow Mayor Cassandra Coleman said the city had turned into a traffic interchange.
"I've never seen this amount of traffic through Lithgow before and I grew up [here]," she said.
"Those who live in Mort Street specifically, they are feeling the full impacts of noise as early as four o'clock in the morning, and they can't get out of their driveways."