
PHOTO: PETER MCINTOSH
The work, called rock scaling, removes potentially unstable or rotten rock.
Rock faces near roads are often monitored after winter as they become weathered.
NZ Transport Agency senior network manager Chris Harris said the pair had been using mechanical means such as bars and airbags to remove rock from the face.
The work will continue today.
A speed restriction was in place and the road reduced to one lane while the work happened.