"We are now at a point where we need to install soil anchors into the slip faces. This requires machinery that needs to be placed in the existing road corridor, which prevents vehicle access past the site.
"The closure is only expected to last two days. However, an additional day or two may be needed should we encounter any unforeseen issues."
She said work to date had included drilling through lahar material, which can be extremely hard work and as such had slowed progress.
A further closure will be required in late November or early December for shotcreting (spraying of concrete) to stabilise the new slip face, she said.
"This work involves a crane, which will be set up at road level, and will be placed across both lanes. We will communicate the exact date of these closures closer to the time, once we can state with confidence when they will occur."
While the road is closed, routine road maintenance activities, such as vegetation control and signage maintenance, along with road surface repairs, will also take place.
The work to repair these slips is complex, with the majority of activity being undertaken below the road to minimise impacts.
Waka Kotahi said it expected the road to be fully repaired, and back to two lanes, before Christmas.
