17 hours ago
Evacuations ordered as heavy rain lashes top of South Island
Hydrology teams have been working through the night to monitor Marlborough's Wairau River, because of fears a small town could be flooded.
A state of emergency is in place for the area around the town of Spring Creek, and people in about 60 homes must evacuate by 9am today.
Emergency management controller Richard MacNamara told Morning Report a floodbank damaged by the Kaikōura earthquake may not hold as the river's level rises in heavy rain.
But he said the latest modelling from the MetService from around 11pm last night was showing a lessening of the rainfall, which meant the flow in the river would be less.
"Currently our own hydrologist are talking around 3000 cumecs, the biggest flood we've had here in recent years has been around 6000," he said.
"But the hydrologists are concerned if we get anything over 4000 and rising then that stopbank beside the township of Spring Creek will come under threat."
At this stage the evacuations are still going ahead, but further decisions will be made once it's daylight and the latest information becomes available from MetService and hydrologists, he said.
Emergency management has people on the ground at the moment to ensure that the 60 households which are under a compulsory evacuation order are moving, he said.
"We've got the support of our local iwi with the marae being opened up, we've got support from Base Woodbourne, NZDF have been fantastic in having some support crews having unimogs etc available if we need them."
But at this stage the Wairau River bank was still holding, he said.
"It's starting to suggest that we may not reach those threatening levels - which is a good thing."
The peak problem was likely to be somewhere between midday and mid-afternoon, he said.
There is surface flooding in town and in the urban districts, as well as on State Highway 63 and various feeder roads coming into Blenheim, he said.
The damage to the stopbanks occurred during the 2016 Kaikoura earthquake, but it didn't come to light until floods in 2021, he said.
"The council has secured funding with the government to secure funding for that."
In the meantime the left bank of the river has been opened up to allow flood waters to flow out, but it still leaves townships on the right bank vulnerable, he said.
"It's a big job with over 1km of stopbank and they've got to dig it all the way out, so they need the right conditions, they need the right gear, they need sufficient funding to do that job. That's all in place, but in the meantime we still have to deal with this constant threat to that community."
