As Christchurch's flooded Heathcote River overflows, residents of the flooded area are being evacuated in boats, unable to leave on foot.
The violent storm passing over the South Island has left many stranded, thanks to torrential rain and metre-high floodwaters.
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The Heathcote River has flooded almost to the front step of surrounding properties.
As high tide hit, Surf Lifeguards helped evacuate the properties, both on Friday night and on Saturday morning.
Matt Dempsey, a member of the Civil Defence and Coastguard rescue team, says they are "advising [residents] to be prepared for evacuation and gather valuables accordingly".
Chris Gregory from Civil Defence operations tells Newshub although flooding is occurring all over the region, "the Heathcote area is of particular concern".
"It's only going to get higher due to high rainfall and high tide," he says.
Cordons are currently in place, both to assist people in leaving the area and restricting others to get back in.
"It's an evolving situation we're monitoring closely," says Mr Gregory.
Council operation controller Mary Richardson says they're only recommending people try and evacuate "if they can do so safely" in the rising waters.
"That's anything below knee level. If it's above knee level when they walk outside, they shouldn't go; they should stay at home and contract call centre," she tells Newshub.
The interagency response has called in service from agencies all over the region, including the New Zealand Fire Service, St John, DHB, Ngai Tahu, NZ Army, Community Public Health and a strong volunteer response.