A community in rural Carterton remains cut off after a landslide caused flooding and closed the district's Kaiwhata Rd.
Heavy rains plagued the North Island's east coast this week.
The downpour left more than 600 people in Hawke's Bay in emergency housing, and caused chaos on Wairarapa's roads.
Measurements showed a month's worth of November rain dumped on Masterton over 12 hours on Tuesday.
Last year, a massive slip dammed the Kaiwhata River between Te Wharau and Homewood, also forcing the closure of Kaiwhata Rd.
This week's downpour has caused another slip, diverting the river flooding which closed the road once more.
Carterton District Council [CDC] staff today piloted a drone to assess the damage.
Council community services and facilities manager Carrie Mckenzie said people should stay out of the area.
"The dam is unstable and could give way due to the pressure from the water build-up."
McKenzie said an assessment of the drone footage is under way, but the road is likely remain closed for several days.
The council is keeping the residents of four properties in the area informed of developments. McKenzie said none of the residents were at home.
Two of the homes are upstream of the slip, and two are downstream, and could be threatened if the dam breaks.
The June 2019 incident saw the dam caused by the slip eventually break, sending an estimated 600,000m3 of water charging downstream.
McKenzie said the council was working with GNS, the Crown Research Institute devoted to geology, to "ascertain potential outcomes".
Last year, GNS' landslide response team was called in to make a risk assessment and help with the response.
Tuesday's heavy rain also saw surface flooding and road closures on coastal South Wairarapa roads.
Landslips closed Tora Rd, outside Martinborough, and cut White Rock Rd down to one lane.
Those roads are now open again.
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