A large slip on the Pahiatua track will cause more delays for some motorists on Thursday morning.
The police say mud and water is covering the westbound lane near the lookout and motorists should be careful when travelling on the road.
The slip comes at a bad time for lower North Island commuters, as the track is currently being used as an alternative to the Manawatu Gorge, which has been closed since August.
Continuing slips have hampered efforts to re-open the gorge road.