A ferocious storm has buffeted the lower South Island of New Zealand overnight, with three states of emergency declared in Christchurch, Timaru and Otago and the city of Dunedin accessible only by air.

The southern city of 120,000 people was cut off by road after major landslips blocked access. Small coastal communities on the Otago Penninsula are also cut off.

More than 200 troops from the New Zealand army were deployed to assist with civil emergency efforts as the rain continued to hammer down. Livestock in Canterbury and Otago were urgently being moved to higher ground with numerous rivers rising to near historic levels and threatening to burst their banks.

It is the second largest flood of the Taieri River in Otago on record.

Overnight and on Saturday morning hundreds of people were evacuated from low-lying homes in Dunedin, Timaru and the wider Otago and Clutha region, with civil defence in Otago improvising ways to close roads after they ran out of flood warning signs.



Power was also out in hundreds of homes in the affected regions.

“We are dealing with a very severe rainfall event,” said civil affairs minister Nathan Guy, who flew to Dunedin on Saturday to assist local authorities.

“We are up against a very strong king tide so some of the floodwater will take time to recede.”

New Zealand prime minister Bill English addressed the situation on social media on Saturday.

“My thoughts are with those affected by the weather events in the South Island. Please follow official advice and take care of each other,” he wrote on Twitter.

Chelsea Ryan lives several hundred metres from the ocean at the seaside community of Brighton, a few minutes down the road from the community of Taieri Mouth.

She and her partner spent Satruday morning helping a neighbour clear out her garage as it started flooding.



“The ocean is so high, it’s really intense and the waves are crazy. There is a lot of water around and we’ve run out of wine so we’re heading in to town now to restock.”

Not a good time to be farming/living on the Taieri Plain pic.twitter.com/7OcMUISc52 — Grant Vickers (@Otago12) July 22, 2017

Lisa Dorahy from the suburb of St Clair in Dunedin said her family was evacuated from their home by police at 9am on Saturday morning after a night of torrential rain and gusty winds caused a significant piece of the hillside to collapse opposite their home.

“Having three children made the situation more serious for us. We only had time to grab one toy each, a change of clothes and our puppy before we left the house.”



“At the time I felt like I needed to prepare for the worst, not knowing if this was going to be a long or short term situation.”



Nine people were rescued by the army overnight in Mosgiel after their cars became stuck in rapidly rising flood waters and hypothermia was beginning to set in when they were located.

The Heathcote River in Christchurch burst its banks and Christchurch mayor Lianne Dalziel declared a state of emergency just before midday, with the army sending more than 100 troops north from Oamaru to assist with possible evacuations.



In Christchurch and Dunedin several wastewater pumping stations were unable to keep up with the deluge and contaminated wastewater flowed onto city streets.

I think this is something like the third once in two hundred years flood in Christchurch in the last four years pic.twitter.com/vsuolDS81i — Finn Jackson (@Finnsmemes) July 22, 2017

The rain was expected to continue in the South Island for most of Saturday and the New Zealand Transport Authority was asking people to avoid all non-essential travel and stay home.

In the last 24 hours the Metservice recorded more than 220mm of rain on the hills north of Dunedin, 162mm in Oamaru and 104mm in Ashburton.

Another 30 to 50mm of rain was expected to fall on south-eastern parts of the South Island on Saturday, according to the Metservice. Heavy snowfall is also expected in Central Otago.