Dunedin escapes the worst as flooding swamps Oamaru and Waitaki declares an emergency

The rare red rain warning that hung over Dunedin from Sunday afternoon was lifted at 10am on Monday, and the city has come through the night in better shape than many residents feared. The worst of the storm landed instead on Ōamaru, where an intense burst of rain shortly after midnight flooded homes and shops and pushed the Waitaki District Council to declare a local state of emergency.

In its Monday update, the Otago Civil Defence Emergency Management Group said Ōamaru received 34mm of rain in the two hours between about midnight and 2am. Across the wider event, up to 160mm fell in parts of Dunedin, causing surface flooding and many dozens of road closures around the city and the Taieri Plain.

A state of emergency in Waitaki

Waitaki District Council declared a state of emergency at about 4.30am on Monday. “More than 20 people have self-evacuated, and severe surface flooding is being experienced across the district,” the council said in a post on its Facebook page.

Fire and Emergency southern shift commander Daryl Ball said crews took about 70 calls overnight, most of them in Ōamaru and Mosgiel, and were only able to attend just over half of them because of the extent of the flooding. Flood response crews helped 18 people evacuate to the Ōamaru Fire Station, and civil defence said about a dozen residents and four dogs were sheltering at the community led evacuation centre at the Network Waitaki Event Centre.

Nobody was reported hurt, but Ball said a large number of cars had been driven into floodwaters. “We’ve managed to push most of them off the road, but they’re all sitting on the side of the road,” he said. His advice to anyone unsure about leaving was to evacuate early rather than wait.

Waitaki Mayor Melanie Tavendale told RNZ’s Morning Report the flooding was widespread. “So we’ve got a number of Oamaru CBD areas, both houses and businesses, that have been flooded,” she said. Emergency Management and Recovery Minister Mark Mitchell, who travelled south on Sunday night, joined her for a media briefing at about 12.30pm on Monday.

For some residents the water came with almost no warning. Ōamaru mother Milli Maxwell told the Otago Daily Times she woke to her cat meowing at about 3am and found her house already flooding, a metre or so deep at its worst. Both cars in her driveway were flooded halfway up the doors. “I’m so gutted,” she said.

Overnight in Dunedin and Mosgiel

Dunedin’s heaviest rain arrived between 2.30am and 3.30am, when the city council described a significant deluge hammering the city. Mosgiel took more of it than the central city. The council had four pumps running in Reid St overnight with three more on the way, and an evacuation centre opened at the Taieri Bowling Club for residents who chose to leave. By Monday morning the flood risk had eased and the centre had closed.

“South Dunedin looks to be okay because the pumps and the pipes are working there, our main concern is around Mosgiel because they’ve actually had significantly more rain than we’ve had right here in Dunedin,” Mayor Sophie Barker said on Monday morning.

Despite reports on Sunday night, including our own, that a state of emergency had been declared in the city, Dunedin did not declare one. The city ran its response through its emergency operations centre, keeping a close watch on the Silverstream as runoff from the deluge drained toward it, while the Water of Leith and Lindsay Creek in North East Valley ran high but still had capacity in reserve. Council staff also worked with the University of Otago’s campus welfare team overnight so students could be moved out of flats quickly if it came to that.

The council’s overnight message to residents had a distinctly Dunedin flavour. “Stay safe, stay inside, and please do not drive out for a little look-see. The wake of vehicles will push surface flooding off the road and into shops and homes, we don’t want that.”

Emergency operations centre controller Sandy Graham said flood protection barriers installed in Surrey St and the pumps and pipes across South Dunedin had managed the rainfall. “Our stormwater network continues to work within capacity,” she said. Incident controller Chris Henderson thanked crews, contractors and emergency services on Monday morning. “We have had significant rainfall over the past 24 hours and it is not over yet. While our stormwater network continues to work well, there is surface water in parts of the city.”

Damage reported in the city on Monday was localised. A landslip brought a tree down on power lines in Blanket Bay, cutting power to about 20 properties from mid morning, with lines company Aurora estimating restoration by 4pm.

Roads, buses and snow

At the time of writing on Monday afternoon, the NZ Transport Agency’s live journey map still showed State Highway 1 closed by flooding between the Waitaki Bridge and Ōamaru, and State Highway 87 closed by snow between Kyeburn and Outram. The Lindis Pass and the stretches of State Highway 85 that were shut overnight had reopened under snow and ice warnings.

In Dunedin, Three Mile Hill Rd and part of Kaikorai Valley Rd remained closed by surface flooding on Monday morning, and a fallen tree blocked part of Portobello Rd near Bacon St, with no buses running beyond Broad Bay. Several small slips were reported on Otago Peninsula. Sandbags remained available at the Mosgiel Memorial Park gym car park and the Dunedin Ice Stadium car park.

Inland, heavy snow closed highways through Central Otago and the Maniototo overnight, blanketing towns like Naseby. Civil defence said road access between Ranfurly and Alexandra, and between Outram and Middlemarch, was being re-established during the day.

Warnings still in place

MetService meteorologist Paris Marshall said the red warning for coastal Dunedin and Clutha would be lifted from 10am. “The intensities are generally decreasing as that rain band loses steam, but even with this decreasing trend this rain is still falling on what has been accumulated through the night and early morning,” she said.

In its 10am update, published through Otago’s civil defence alerts, MetService kept an orange heavy rain warning in place for coastal parts of north Otago until 8pm on Monday, with a further 20 to 40mm expected on top of what had already fallen. The system is now moving up the island, and parts of Marlborough and Canterbury are under a red warning running into Wednesday. Otago’s civil defence group said most rivers in the region had peaked, though rivers in North Otago could still rise during the day, with Otago Regional Council staff continuing to monitor them.

The weekend’s alert was the sixth red warning MetService has issued this year, and the 25th red warning event since the top tier was introduced in May 2019, the forecaster said.

South Dunedin’s flood defences

South Dunedin spent Sunday bracing for a repeat of the floods that swamped hundreds of homes in 2015 and forced evacuations under the last red warning in 2024. Volunteers filled sandbags at the Ice Stadium for hours, and the council closed Surrey St early and installed flood barriers at the suburb’s most notorious trouble spot.

This time the defences held. The suburb’s pumps and pipes kept pace through the night, a result that will be studied closely as the city weighs its long term adaptation plans for South Dunedin, which could see up to 1700 homes bought and cleared in the decades ahead. One wet night does not settle that debate, but this time the pumps, pipes and barriers did what they were built to do.

Were you flooded in Ōamaru or Mosgiel overnight, or did your street stay dry this time? Tell us what happened in the comments below.

This article was written by AI, briefed to report the facts, hopefully without some of the bias people bring to the job 🙂