South Wairarapa hit by more heavy rain after last week's deluge

South Wairarapa residents are waking to assess potential damage after forecast downpours kicked in last night.

The wider region has been under a heavy rain warning since Wednesday at 10am, which is expected to lift at 6am on Thursday.

The deluge comes only a week and a half after torrential rain knocked out a bridge - isolating close to 500 families - submerged farmland and closed roads.

Rain fell intermittently on Wednesday, but by evening South Wairarapa councillor Aidan Ellims said the system that earlier slammed into the South Island had landed.

"That weather has now arrived out here. Heavy rain and heavy wind now. We"ll see what it all looks like in the morning..."

South Wairarapa deputy mayor Rob Taylor told RNZ it was "bucketing down" about 6pm.

He said he was keeping his fingers crossed for better weather this Matariki weekend to attract visitors to the region.

Taylor said the recent bad weather had hit the region's economy hard.

"Martinborough and Greytown are expecting large numbers of visitors, which we are reliant on.

"That rain event we had two weeks ago had a significant impact on the local economy, with vineyards, cafes and restaurants having to close."

Some of the mess caused by that storm was still evident on rural roads east of Martinborough on Wednesday as more rain came in.

A stretch of White Rock Road buried in gravel 10 days ago was once again underwater, with piles of gravel 1-2 metres high on either side of it.

Ellims said the Awhea River flooded badly, covering the road and cutting off access.

"We can see there's a lot of metal that's been washed out of the river and onto the road because the road is low-lying ... and may well be lower than the riverbed itself.

"This metal has had to be cleared off the road to allow it to be passable for the locals."

He said locals ultimately wanted the entire stretch of road between Tuturumuri and Lagoon Hills to be raised so they could reliably get between Martinborough township and home.

Ellims said the road was used daily by farmers on the eastern hills as well as stock trucks and permanent residents on the coast.

"This is the only road that provides access to White Rock, Tora... and Te Awaiti."

He said the current bout of rain was landing on already sodden ground, and hilly farms were scarred by slips.

"One of the farms... had 500mm of rain over 48 hours... so that's huge, 500mm is half a metre of rain.

"There's slips on farmland all over the place, that has resulted in pasture being stripped and ripped away, washed down into rivers.

"Those farmers were relying on those paddocks in the next few months for ewes to be lambing on and it's going to take a long time for those paddocks to recover.

"Not only that, those slips have washed out fences so paddocks are no longer stock proof.

Hamish Sims - who runs sheep and beef at Awanui farm - said the rain less than two weeks ago was a record.

He said on his property there were "significant" slips and paddocks along the river valley road copped it, although he said much of the damage was superficial.

"It looks bad on the fences, there's a lot of debris on the fences but we're more interested in ... making sure the paddocks are stock-proofed," Sims said.

"It's easy for us to go and fix that stuff down through the valley, in the hills it's a different story going and fixing fencing at this time of year - that's the big issue.

"It's going to take us 10-12 months to get back to where we want to be."