A large landslide has blocked the Kaiwhata River in the Wairarapa.
GeoNet's landslide response team said on Thursday it is investigating the event, which reportedly started on Saturday, 1 June.
"The team will be using a drone, GPS and a terrestrial laser scanner to provide detailed hazard information to local authorities," GeoNet said on its Facebook page on Thursday.
"This information will help with their management of life safety and property risks."
Sally Dellow, an engineering geologist from GNS Science, told Newshub that the local community will be informed of any potential risk to life and property in the first instance.
Greater Wellington regional council and the affected territorial local authorities in Carterton and Masterton are managing possible risks to local residents.
The data collected on Thursday will help in assessing potential impacts on nearby residents, including the risk for upstream flooding and the extent of possible downstream flash flooding if sudden failure of the dam occurs.
Dellow said the landslide resulted from a failed slope between a pre-existing landslide and the river.
The 22km river is located in eastern Wairarapa and flows to the southeast of Masterton.
"Rain in the area on Friday/Saturday [is] a potential trigger... Rainfall data from the local community will help us determine if this is what triggered the landslide," Dellow said.
Newshub.
