Southland residents are worried their homes and baches at a small beach community will be swept into the Waiau River as swift waters claw into the banks.

A local state of emergency was declared for Bluecliffs as the river swells from recent heavy rain, taking gravel and sand with it.

Residents said they had been calling for action for more than a year and now faced evacuation.

The quiet community is mainly baches but more permanent residents have moved there in the past decade.

Bluecliffs resident Joan Redpath said there used to be a wide gravel and grassy bank they would whitebait off behind her house. Photo: RNZ / Tess Brunton

Behind Joan Redpath's house, steps used to go down to a wide gravel and grassy bank where her family would whitebait from, looking out towards the sea and a long gravel spit.

Now the steps just drop off into the Waiau River.

"We probably lost a good 10 metres overnight of that gravel bar and it's pretty frightening," Redpath said.

The river had always moved and taken a little bit of sand and gravel away during floods or when water was let out of the hydro lakes upstream, she said.

Photo: RNZ/Tess Brunton

But in June 2023, the river mouth started to move east and the spit between the river and ocean stopped building up, washing away a massive amount of land and a chunk of the road.

She said residents had asked local councils for action, but that had not happened.

Photo: RNZ/Tess Brunton

Down the road is a former landfill that now has water lapping against it.

The Southland District Council was going to clear it as they were worried it would wash into the river," Redpath said.

"So they started digging it out and then it was reported that there was explosives there so all the work stopped... It's just been closed with a big fence. But unfortunately the last few days, that fence is now in the river."

Redpath said many residents had "nowhere else to go" and the situation was upsetting.

"None of us want to leave ... as silly as that may sound, this is home."

Henry Thompson. Photo: RNZ / Tess Brunton

Henry Thompson has owned a crib in the area for 30 years.

"Some of the fellas have got their cribs very close to the bank and the river and the seas come right in ... the sea has only got to knock that spit down and it comes right over up to the bank where the cribs are and it washes the bank away and that's what will happen. The cribs will end up in the river."

He had been worried about his crib for the last three to four years.

"The council - all these different ones, Environment Southland - they're all not worried about it. They couldn't care less about it. They don't want to do anything with the place."

Tuatapere resident Garry Reid was checking on a friend and said so much land had been swept away.

"Could be a good 20-30m of land is gone from down here where all the white baiters camped. There used to be caravans and everything down there and tent sites. This year they couldn't do that."

Garry Reid says people used to camp, whitebait and even drive next to the Waiau River, but now that's all covered in swiftly flowing river. Photo: RNZ / Tess Brunton

Emergency Management controller Simon Mapp said declaring an emergency meant steps could be taken to open the river mouth bar to prevent further erosion.

But he said it was a very difficult engineering task and the risks had to be weighed up.

Meanwhile, residents faced a nervous wait after being asked to prepare to evacuate at short notice with more rain expected over the weekend.

Photo: RNZ/Tess Brunton

Southland District Mayor Rob Scott told Morning Report the council and regional council had been "actively involved" with the situation in the township since June 2023.

The regional council had been there "pretty much every week" since September, when the area flooded, and had been monitoring the river levels and mapping the township with drones.

A public meeting had also been held in Tuatapere in August.

"It's a very dynamic situation out there with the river mouth moving up and down the bar, so it was actively starting to improve until it all of a sudden got a whole lot worse," Scott said.

Officials were "doing everything that we can" for the residents, he said.

They were not being asked to evacuate yet, but officials were keeping a close watch on the situation.

Accommodation had been set up in Tuatapere for anyone who wanted to leave or felt unsafe.

"We totally understand that it's not a nice situation for them at all and we're working with them closely."

It was a "possibility" that two homes could be swept away - maybe more if the erosion worsened, Scott said.

However, the river level had dropped 1.7 metres over the past two days, so he was hoping the properties could be saved.

Tess Brunton, Otago/Southland reporter

Reproduced with permission