"It's a critical time of year - particularly for the dairy sector that are only one, two or three weeks away from calving.''
Mr Woodhead also called on people feeling overwhelmed to contact the Otago Rural Support Trust for assistance.
Farmers who remained evacuated from their properties should follow the advice of authorities, he said.
"We know people that have been evacuated are anxious to get back to their homes as soon as they can, but please follow the advice we give around that."
Who to contact
• Federated Farmers 0800 FARMING (0800 327 646)
• Otago Rural Support Trust 0800 787 254
• www.rural-support.org.nz.