A slip across a section of Helena Bay Hill is being cleared and the road remains open.
Peter Brown of The Gallery and Cafe Helena Bay Hil, said he had been phoned and alerted to the slip which he understood had come down about 8.30am on Monday.
"I went down there and saw a guy on the other side with a small digger who cleared the road enough to let traffic through," Mr Brown said.
A larger digger was seen heading to the slip about 11am. Whangarei District Council staff were assessing the site.
It's not the first time a slip has caused major traffic disruption for regular users of the steep road.
A decade ago, storms dumped plenty of rain on the region causing the waterlogged hill to slip across the coastal road. Residents living in the area had to use a long detour through rough roads to get to Whangarei.
The repair job, which cost $900,000 involved constructing a rock buttress and retaining walls, and back filling the hole in the road with about 150 truck loads of suitable aggregate.
The road was reopened four months later.