It was the result of a one-in-20-year flood which cut off access between Ashburton and South Canterbury, with flooding across State Highway One and at the Arundel Bridge on the inland scenic route.
Federated Farmers South Canterbury provincial president Jason Grant said the exact number of farmers affected was unknown, but up to 30 farm properties had suffered differing degrees of damage.
“The number is probably between 20 and 30. It’s complicated as there are a lot of farms affected to varying degrees from flood water covering up to 50% of their properties to other properties with small surface flooding of some paddocks.”
He said the damage ranged from debris-covered fences with broken wires and pulled out posts to damaged irrigation infrastructure, broken irrigators, broken underground water pipes and water damaged pumps and pump sheds.
There was also silted pasture, which stock were unable to eat, and uprooted trees.
“The river has carved out areas of ground and lane ways,” he said.
Environment Canterbury staff were still closely monitoring rivers around Canterbury with ongoing rain forecasts in the Rangitata catchment.
An ECan spokesperson said significant flows were still going down the South Branch.
‘‘But ongoing works are occurring in the river to divert this water back into the main channel. We expect the flow in the South Branch to reduce slowly ... the river system is in a very sensitive state and even with these lower flows changes in flow patterns are possible, which could result in overland flow paths changing.
“All residents in the area are advised to be wary of these possible changes.’’
The work would relieve ‘‘ongoing flood outflows’’ and improvements would slowly happen, but works to restore flood protection would take much longer (weeks to months) and the river would remain highly vulnerable to any future weather events.
Mr Grant said any people wanting to offer help with clean up could contact the district's Rural Support Trust network on phone 0800 787 254.
Offers of feed, needed for livestock that had either been relocated, or restricted to certain areas of farms, can be made directly to Federated Farmers on phone 0800 327 646.
DairyNZ has urged farmers affected by flooding on the West Coast and around the Rangitata catchment to reach out for help if they needed it.
The ‘‘ferociousness’’ of the rain took many farmers by surprise, DairyNZ South Island hub lead Tony Finch said.
It was worth taking the time to look ahead by creating a feed plan; assess current feed resources and cow condition, and damage to infrastructure.
Impacted farmers were affected by damaged infrastructure, rivers cutting new paths through farmland and silt accumulation across land. That had been compounded in some areas by bridges and roads out of action affecting milk collection and services such as AI.
Agritech and herd improvement co-operative LIC had been using small planes and helicopters to make sure semen straws were still delivered to farmers on time.
