Precautionary evacuations took place when the North Branch of the Ashburton River caused plenty of concerns after breaching its banks on Saturday.
Environment Canterbury and Civil Defence had to respond to the river breaching its banks and take quick action to avoid a much larger flooding issue.
Sitting Councillor Ian Mackenzie said the rain at the weekend had the North Branch come up faster than any of the other tributaries and at the Ashburton Forks it breached its banks to be flowing out of the river bed but inside the river terrace.
“But it back-flowed into an irrigation pond up there at one stage and there was real concern the irrigation pond was going to let go.
“Water was flooding out on to Ashburton Forks Road, and Civil Defence evacuated a few houses that would have been caught had it been breached.
“In the meantime they got in a digger to relieve the pressure on the dam which put the water back down through farm land, but back towards the river, which saved the day.
“It was a near run thing.”
The North Branch was still flowing out of its riverbed on Monday, Mackenzie said, “which poses a significant challenge to get it back in”.
It is another example of more work and funding needed to combat an increasing trend of flood events.
Mackenzie, a co-chair of ECan’s catchment committee, said the river engineering team was doing a good job on the repair works from the 2021 May floods, and was on course to spend $20m across Canterbury.
He said a meeting on Wednesday will have ECan’s engineering teams “quantify the damage from the series of four floods we have had”.
“The issue with the damage is there isn’t a bottomless pot of money for us to chip into.”
ECan had funded the May floods recovery with a special general rate, which Mackenzie said has left the river scheme reserve intact.
“So there is a pool of money for our engineers to use to help fix up the new damage, depending on what the quantity is.”
ECan will also seek potential recovery funding from the National Emergency Management Agency, he said.
The Ashburton District Council’s roading team is also in the process of assessing the scale of fresh damage to an already battered roading network.

• By Jonathan Leask