Evacuations could begin if heavy rain continues to fall and river levels rise, warns the Ashburton Mayor and the Acting Minister for Emergency Management.
During an update on the weather situation in the region, Mayor Neil Brown and Kris Fafooi said officials are keeping an eye on river levels to see if evacuations are needed.
It comes as a state of emergency has been declared in the Timaru District and Ashburton, the latter which has been declared for seven days.
Rain is set to continue for the next 24 hours.
Brown said this afternoon that officials are monitoring the situation after heavy rain overnight which began in the Ashburton high country, is now making its way down through the river systems.
"The Ashburton River is one we are concerned about - we want the water to stay in the river.
"There is still plenty of capacity in it but we are keeping a watchful eye on our stopbanks," Brown said.
He said there was about three-four metres of capacity in the river yet, saying the river was probably at "half capacity".
"So still a bit of room to go but we are keeping an eye on it."
He said it was still raining in the high country as well as in the township of Ashburton which has a population of about 35,000 people.
"We need it to stop raining to let those rivers drop."
Brown says evacuation preparations are in place should the stopbanks break.
Police have advised some residents to evacuate already.
Fafooi says a lot of work has been done in the Civil Defence group for the region.
"You may have seen the Defence Force here and also there has been messaging going out to all the communities that may be affected and may be evacuated, to take steps to prepare for that."
Brown said if stopbanks broke on the northern side of the river about 1700 people would need to be evacuated. If it broke on the southern side, about 2200.
The man was clinging to a tree as waters rose around him before being rescued. (Source: Other)
"We are planning for that at the moment. We will be letting them know if they need to know," he said.
The call would be made during daylight hours so that night evacuations would be avoided.
Brown said farmers had been moving stock "all day".
"They will be needing some support in the future too," he said.
Fafooi said updates for parents and caregivers ahead of school tomorrow would be provided "soon".
Brown said he'd been in the region all his life and had never seen river levels so high.
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