Disaster recovery work on Putty Road will include steel nails, up to 12 metres long, being drilled into steep slopes next to the regional thoroughfare southwest of Mount Thorley.
Putty Road was significantly damaged at Terrys Creek during severe weather in June 2022, which resulted in multiple landslips.
Work on permanent repairs at nine locations along the three-kilometre stretch will start on Monday, January 22.
The Albanese government's Emergency Management Minister Murray Watt said it was a "significant transport route".
"As crews continue to work through and complete works like bridge repairs, clearing landslip sites, repairing erosion and installing new drainage, the beginning of soil stabilisation works along this section marks a significant milestone on the road's restoration," he said.
NSW Regional Transport and Roads Minister Jenny Aitchison said the work was about making sure the infrastructure was better protected from natural disasters - not just restoring it to its former standard.
"This work to build back better will include a technique known as 'soil nailing', where specialist crews drill holes into the soil surrounding Putty Road so steel bars can be inserted and grout filled to stabilise the ground and make the road more resilient," she said.
Aside from stabilisation of the slopes, a one-metre wide shoulder will be restored and new guardrails set up.
Some of the work will include 'shotcreting', which involves spraying concrete onto an embankment.
Federal Hunter MP Dan Repacholi said part of the job would require workers to abseil off the face of the slope.
"Different locations along this section of road will require different stabilisation techniques, which includes rock fill, while the length of the individual slopes range from around 60 metres to 190 metres," he said.
The joint federal-state government funded project is expected to be completed mid-2024.
