The highway linking the West Coast and Otago has now reopened to one lane.
State Highway 6 between Makarora and Haast was closed this morning after a rockfall covered the road.
NZ Transport Agency crews have cleared one lane, though delays will remain until the road is completely cleared.
A spokesperson said the highway would close again from 7pm.
Another inspection will take place at daybreak in the hopes of reopening one lane from 8am tomorrow, the spokesperson said.
Crews hope to clear both lanes in the next day or so, but drivers need to prepare for some short delays around the site for the rest of this week.