The earthquake monitoring agency GNS Science is warning more landslips are likely to disrupt the roading network this winter.
State Highway Three in Taranaki was closed by one overnight.
And while it's been a very wet winter, it's not just the rain that is causing so many slips.
The latest one in north Taranaki caused a road closure that lasted almost seven hours, before one lane was finally opened.
A truck driver discovered the massive slip near Urenui at around three this morning.
"Soggy, wet and slippery," NZTA regional performance manager Mark Owen said.
"The challenge there is there were a lot of trees adding weight to the slip so once they cleared up material, they had to remove material to make it safe and get the road open again."
The NZ Transport Agency (NZTA) spends $100 million a year on emergency responses to slips and floods, with constant monitoring of road networks.
"It's a challenge given New Zealand's steep terrain and the severe weather. So it is a challenge for us keeping the roads safe, open and resilient," Mr Owen said.
A slip last month in the Ngauranga Gorge closed five of six lanes on State Highway One north of Wellington.
Ngaio Gorge Road remains closed after a 1300-cubic metre landslide last weekend.
The Wellington region has seen one of the wettest winters on record, with 460 slips.
Manawatu Gorge has been closed since April and may never re-open.
Crown institute GNS says a lot of slips are on slopes modified for road building in the 1940s, 1950s and 1960s.
But it's not just rain that affects stability.
"Slopes start to deform over time and they start to weather the strength of the slopes," GNS engineering geologist Chris Massey said.
"What that means is you don't need as much rainfall or as much ground shaking to trigger the land slides."
The outcome of the Kaikoura slip after the November quake could have been very different if it had happened during the day.
"If you go back to Christchurch we had five recorded deaths from rockfalls and we have a database of over 700 deaths we've recorded since 1780, so landslides in New Zealand do kill people," Mr Massey said.
But he says it's difficult to predict where slips are likely to happen next.
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