Length of closure for damaged Blue Mountains highway revealed

Motorists and residents severely disrupted by the closure of a crucial motorway over the Blue Mountains will need to wait up to a further year before a new bridge structure over the damaged section is built and opened to traffic.

A closed stretch of the Great Western Highway at Victoria Pass is now expected to reopen between April and June next year, which means it could have been shut for 15 months by the time major construction is completed.

The section of the state’s major east-west link at Victoria Pass has been closed since March 9 after engineers found serious cracking and ground movement in a stone causeway built by convicts nearly 200 years ago. The road defects and bulging of sandstone walls risked the causeway’s collapse.

A bridge structure will now be built over the existing Mitchell’s Causeway, supported by deep piles anchored into stable bedrock below. The new crossing will sit above, but independently of, the convict-built causeway, which will be stabilised as part of the work.

The new crossing over part of the highway that is often labelled a goat track and is just one lane in either direction will also provide an extra lane of traffic.

Following confirmation of the time that the motorway will remain closed, an extra $20 million in support will be provided by the NSW government for small businesses experiencing financial hardship, expanding on a $3.6 million package in May.

Grants for small businesses in Mount Victoria, Hartley, Little Hartley and Hartley Vale will increase to up to $25,000, from $10,000, while those eligible for up to $10,000 will be expanded to take in businesses in suburbs of Lithgow, Oberon and Blackheath.

Contracting company Seymour Whyte was selected from two consortia shortlisted in May to build the new crossing. It is expected to start major construction next month, but the government is yet to reveal what the new crossing will cost taxpayers.

Roads Minister Jenny Aitchison acknowledged the length of time the highway would remain shut would present difficulties.

“I know it will mean sitting down at the kitchen table, working out how your family moves around and what the next year looks like in practice,” she said. “But I want to reinforce what this also means: we have a timeline, contractor and major construction on the new crossing beginning in July.”

She described the planned new crossing as a permanent solution and not a Band-Aid fix for the section of highway at Victoria Pass that had been used by up to 12,000 vehicles a day.

Geotechnical testing had found the bedrock under the causeway remained strong, which meant the same alignment could be built upon. This has averted the need for an alternative route to be built, which would have been more costly and taken a longer time to complete.

Since the highway was closed, motorists have had to use Darling Causeway and Chifley Road for a 25-minute detour. This has also placed financial pressure on business owners who relied on passing traffic at places such as Little Hartley in the Blue Mountains.

Aitchison has previously not predicted how long the highway will be shut, though Premier Chris Minns had conceded it would require a “complicated rebuild”, which would “not be quick”.

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