The badly damaged State Highway 1 south of Kaikōura could be open as early as next week.
Kaikōura residents have had limited access in and out of the township since the earthquake on November 12, with contractors working around the clock to get the main road open again.
The New Zealand Transport Agency (NZTA) says it's aiming for a mid-December target to get the highway open to one lane, subject to weather and further aftershocks.
There are 29 slips blocking the highway. Abseilers are using hands and feet to loosen rock above the road, while monsoon buckets wash away debris.
"I think they're pretty special people, but that's what they do for a job and they just get into it," Downer operations manager John Wood says.
"What we're trying to do is, by the time we open it, we have got it safe," NZTA regional performance manager Peter Connors says.
"We understand how vital it is to get this highway open. Crews are working hard to remove the slip material as quickly as they can to restore access to Kaikōura from State Highway 1, but we also need to ensure the safety of workers on the ground, and the hazardous nature of blasting work means that it must be undertaken with care."