The Manawatu Gorge closure is set to last until the end of this week as workers clear the last of the loose material.
Thousands of cubic metres of rock, dirt and other debris has been cleared over the past month, after three slips came down on to the road.
The NZ Transport Agency resumed their efforts over the weekend after bad weather brought the clean-up to a halt.
Heavy rain has helped bring down the remaining material sitting above the May 14 slip.
Workers were able to safely return and are continuing to remove the debris.