Over 80 road restrictions in Tairāwhiti as council struggles to keep up with multiple severe weather events

More than 80 road restrictions are in place in Tairāwhiti as the Gisborne District Council faces another colossal clean-up following last week's rain.

Tairāwhiti Civil Defence says approximately 50 people have been cut off after Tauwhareparae Road, north of Tolaga Bay, was so badly damaged it looks like it's been hit by an earthquake.

Tauwhareparae Road looks as though an earthquake has struck but it is simply the result of constant rainfall.

"We've got a number of issues on Tauwhareparae Road. The biggest one we've been looking at is at the 18km mark - it's a site locally known as the 'Doonholm Slip'. There's been significant damage through there," Tairāwhiti Civil Defence controller David Wilson said.

"The team of engineers have been up in the air today to have a look at it to try and get an assessment of what our next steps are going to be."

It's a major inconvenience for those who work in the area. 

"Typically, this property I've got on the market, I would access via Tolaga Bay, up through the Tauwhareparae Road, which was a nice sealed road," Bayleys real estate agent Jacob Geuze said.

"Now, I cannot go that way and have to go about an hour in the other direction."

And it's just one of the dozens in the region - each red mark represents a road that's been closed.

Gisborne's fourth State of Emergency this year was lifted on Sunday after heavy downpours caused mudslides to tear through homes, re-traumatising residents still recovering from Cyclone Gabrielle.

And now the ground is absolutely sodden.

The ground's soaked up so much water it's like porridge, leading to more slips.

"The ground's absolutely saturated... There's very little we can even do on some of these sites because the slips are still moving," Wilson said.

Auckland University engineering Professor Liam Wotherspoon knows the impact too much water can have on ground movement.

"We're getting more and more water soaking into those slopes... That's building up the loading on those slopes, and then also at the same time that's influencing the strength and reducing the strength over time," he said. 

"So if we get an increase in load and a reduction in strength, at some point we're going to see some sort of failure occurring and that's what we're seeing with the damage to those roads."

But as the number of damaged roads keeps growing, Gisborne District Council is struggling to keep up.