Police are warning drivers to take care in Awakino after a second slip crashed on to the highway hours after a slip had been cleared.
On Monday, mud and rock covered the road about 2.20pm and cut off the vital route north until 7.30pm before contractors had cleared a path.
Then, shortly before midnight, another slip closed the road.
"More came down last night [Monday] but they worked through the night clearing it and reopened it again," Constable Daniel Walter, of Mokau, said.
A 30kmh speed limit was in place but traffic was minimal and flowing smoothly.
"They're working on clearing the dirt and debris off the road and I expect it will be the situation for at least the next 24 hours."
Mr Walter warned motorists to check conditions before travelling.
"It could still come tumbling down. It's saturated from all the rain and often when the sun comes out and you think it's all good, it comes crashing down again," he said.
New Zealand Transport Agency Acting State Highway Manager Karen Boyt said the second slip happened at 11.40pm on Monday but one lane was cleared by 1.15am yesterday.
Road crews would be onsite today, clearing debris and soil off the roadside embankments.
It was not expected to hamper traffic access.
However, Ms Boyt urged motorists to take care when travelling through the slip cleanup area.
"Remember, slow down, drive to the conditions and take note of any traffic controls, signage and speed restrictions in place. We would like to thank motorists for their continuing patience around this clean-up operation."
To check state highway conditions, ring 0800 4 HIGHWAYS (0800 44 44 49) or go to www. nzta.govt.nz/traffic
- © Fairfax NZ News
Should ratepayers fork out for increased security to keep vandals at bay in Pukekura Park?Related story: Cameras set to catch vandals