Spring Creek residents were told to be prepared to evacuate on Friday morning if the Wairau River reached a certain level. Photo: RNZ / Samantha Gee
Residents in the small town of Spring Creek, north of Blenheim, did not have to evacuate today after the Wairau River did not rise as predicted - but compromised stopbanks mean the community remains at risk during future storm events.
The stopbanks that protect around 600 homes from the Wairau River have been described as being at "catastrophic risk of failure" due to previous heavy rain and seismic activity.
Marlborough Civil Defence group controller Brian Paton said it would not be the last time the community had to deal with being evacuated during severe weather, before the stopbanks were fixed.
The Wairau River on Friday. Photo: RNZ / Samantha Gee
Residents of around 70 homes in Dodson, Hathaway and March streets, and part of Ferry Road were told on Thursday night to prepare to leave their homes by 9am on Friday for the day, as the Wairau River level was predicted to rise significantly amid an orange rain warning for parts of the district.
Paton said the decision was made to alert residents proactively the night before, so they had time to prepare.
"We were expecting 250-odd millimetres in the Mt Richmond Forest Park, maybe a little more in some places and in the end, that just didn't occur."
The Wairau River peaked at around 1300 cubic metres per second mid-morning on Friday, instead of the 3600m3 it had been forecast to reach.
Paton said most residents were not surprised to get a knock on their door and the advice that they be prepared to evacuate, given the issues with the Peninsula Road stopbanks.
He said the council and Civil Defence would take a precautionary approach until the stopbanks were repaired.
"If the stopbank fails it is not the case of the water coming over the top of it, where you get a wee bit of a trickle for starters, the potential with this one is that the stopbank will let go entirely."
Paton said if that occurred, those in Spring Creek would experience what Edgecumbe residents did when the Rangitāiki River breached its banks in 2017.
"It would be a miracle if we go another 24 months without another rain event like this ... the 2021 and 2022 storms were pretty horrendous, we really don't want something of that magnitude so we will cross our fingers but we will have to manage the cards we are dealt."
One of the stopbanks started showing signs of cracking after the 2016 Kaikōura earthquake. Cracks started to appear in the lower section of the other one in the 2021 and 2022 floods.
Wairau River Photo: RNZ / Samantha Gee
Spring Creek resident Tim Newsham said while the river had coped with larger flows during those floods, he understood there were now concerns that a lesser peak could cause the river to blow out.
"My wife isn't a very good swimmer and she has always had a fear of the water so she might be off but I'll be staying here with the boat tethered to a tree and looking after the stock and the chattels."
The precautionary evacuation was "a good practice run" for what could eventuate this winter or in the coming years until the stopbank was repaired, he said.
Wairau River. Photo: RNZ / Samantha Gee
Emergency Management Minister Mark Mitchell was on the ground in Spring Creek when residents were told they could remain at home as the risk of flooding had dissipated.
"They were obviously concerned but also relieved and they felt the communication was very good, they were given lots of early warning and they knew exactly what was happening."
He said it was clear that the stopbank protecting the town was in need of additional work and he discussed the future funding for those repairs with Marlborough mayor Nadine Taylor.
The council have costed the repair work, which requires about 35,000 tonnes of rock, at $8.7 million and have asked the government for co-investment.
"The government will partner with them on that, without a doubt, it is a significant repair and some of the issues they are facing are logistical, actually finding the stone they need to reinforce it, but they are working hard on that."
It was far better to be safe than sorry and commended the teams for their early warning, he said.
