Mayor Craig Little said the council was right to trigger a local state of emergency.

The Kowhai river breached its banks at 10.26am.

Follow our liveblog above for the latest updates

Wairoa District Council is telling residents to be ready to leave at a moment's notice.

Wairoa residents received an emergency alert on Thursday night as floodwaters began to rise in low-lying areas.

'Evacuate now. Evacuate to higher ground or inland,' emergency alert says.

Mayor Craig Little said the council was right to trigger a local state of emergency.

Dozens of residents in the town of Wairoa have been evacuated overnight after the river burst its banks.