A Far North councillor is blaming the underfunding of the regions for the road washing out.
Around 20 metres of State Highway 1 north of Kaitaia was wiped out in the rain, leaving a gaping hole in the only road to the top of the island.
Felicity Foy says the region's roads have had barely any seal in the past decade.
"It's out of sight, out of mind. I'd really love NZTA to spend more time in the regions, and resource the regions accordingly.
"We don't have many local roads. We don't have a lot of sealed roads. The State Highway is imperative. Even for this amount of time, [its closure] can have a real impact on our community financially, socially."
NZTA says one lane of the road should be open by the middle of the week.
However, more rain is forecast which could slow down repair efforts.
MetService says heavy rain and possible thunderstorms are expected in the northern and western North Island on Sunday.
Ms Foy says some businesses will struggle without use of the road.
"We are reliant on our primary production sector… that freight. If we can't get that out of the Far North, that has a flow-on effect in terms of the economy."
The NZTA is meeting Sunday morning to discuss further repair work.