The slump on SH2 Remutaka Hill that has required a lane to be closed since August 2 is scheduled to be fixed in time for Christmas.
The eastbound lane of the Hill has been closed with stop/go traffic management in place at the site after subsidence was detected earlier in the year.
Waka Kotahi has confirmed that stage one of the project has been completed ahead of schedule, and the final works are on track to be finished before the holiday break.
Twenty-eight piles have been drilled, and new columns have been placed to ensure the road and hill face are stabilised.
Work will now take place to install 12 anchors as part of the retaining wall construction before the road can be re-surfaced and the side media barrier re-installed.
When the slump on the Featherston side of Remutaka Hill was first detected on July 21, Waka Kotahi reduced the speed limit to 30kmh and instigated regular checks, resulting in the closure in early August after checks showed the ground had continued to move.
“We must close the lane where the slump is occurring. The ground is unstable and poses a risk to road users,” regional manager Mark Owen said in a statement at the time.
An investigation was launched into the cause of the slump and, in late August, Waka Kotahi announced that reparations would include driving piles down to solid rock and the construction of a retaining wall.