Heavy overnight rain has caused a Nelson wastewater pipe to burst, pumping raw sewage into the city’s main river and estuary.
Nelson City Council said the downpours caused a breach in the Paru Paru Rd sewerage main resulting in untreated, diluted wastewater flowing into Saltwater Creek, the mouth of the Maitai River and Nelson Haven.
Mayor Nick Smith said council staff and contractors are working at pace to repair the leak and said it should be done in 48 hours.
“The wastewater is highly diluted from the heavy rain, but it will be unsafe for a number of days to swim, recreate or take shellfish from the Haven.”
Minister for Emergency Management and Recovery Mark Mitchell was at the site this morning and said the council had done a good job in emergency management of the region.
“Nelson’s wastewater system is in much better shape due to a long and ongoing history of investment. I have been impressed by the fast response of Nelson City Council and its contractors to this breach.
“This incident also reinforces the importance of councils investing in improving the resilience of their wastewater networks.”
Upgrades to the wastewater system are part of a plan to strengthen infrastructure under the Bridge to Better project.
Meanwhile flooding and fallen trees have closed roads across the region, including large parts of State Highway 60, SH6 and local roads, while one home has been evacuated.
1News reported that eight homes were evacuated in the town of Brightwater overnight following heavy rain, brought by a trough embedded in a humid northerly flow.
In an update to the Herald at 8.30am, Civil Defence Nelson Tasman spokesperson Paul Shattock said eight homes were considering evacuation but only one ended up self-evacuating.
He said while there was still some surface flooding around, streams and rivers looked to have reached peak levels.
Shattock said weather conditions seemed to be “dying down” and everyone was “safe and sound”.
“The current situation is that the weather has started to ease. River levels are still high, and will start to subside with the rain stopping,” a statement from Nelson Tasman Civil Defence said.
“Response crews are out in the field assisting emergency services. Further road closures may occur.”
MetService meteorologist John Law said around 200mm of rain had fallen north and west of Motueka up through the Kahurangi National Park in the 12 hours to 4am.
That brought the total for some high areas through to a “very extreme” 600mm over 48 hours.
Paradise Peak, which is highly exposed, had received 711mm of rain.
Nelson Tasman Civil Defence asked locals to keep clear of floodwaters, which could be contaminated or contain hidden debris.
“Please take care on our roads. Crews are out in the region and more will be known in daylight.”
New Zealand Transport Agency Waka Kotahi said last night that SH60 was closed between Tākaka and Collingwood because of flooding in Tākaka. SH6 was also closed between Pelorus Bridge and Canvastown ahead of the forecast heavy rain.
“Drivers need to avoid the route or delay their travel until the highway reopens,” the agency said.
In the North Island, heavy rain has brought down rocks in SH2 Waioweka Gorge overnight. The gorge was closed last night as a pre-emptive measure, with an orange heavy rain warning in place till 3pm today.
“NZTA will fully inspect and clear the road as soon as it’s safe to do so and will notify the public when it’s able to be opened.”
The orange rain warning for the top of the South Island has now lifted, while an orange rain warning for Northland was also lifted at 6am.
Northland had received heavy rain in the night, with Kaitāia getting about 60mm to bring its 48 hours total to 150mm, while Kaikohe totalled 133mm, Law said.
Northland suffered significant flooding and 115km/h winds yesterday.
Heavy rain warnings remain for east of North Island
While the weather warnings for the top of the South Island have been lifted, the east of the North Island still faces heavy rain today.
Bay of Plenty and Rotorua are under an orange heavy rain warning until 3pm today west of Whakatāne, while east of Whakatāne and the Gisborne/Tairāwhiti ranges north of Tokomaru Bay are under the orange heavy rain warning until 6pm, with thunderstorms possible today for all those areas.
Law said the northerly caused the hills on the Bay of Plenty’s southern edge to act like a funnel.
“The rain comes, feeds in, pushes through towards parts of Rotorua and those hills in the east as well.”
MetService’s website warns streams and rivers may rise rapidly, with surface flooding, slips, and difficult driving conditions possible.
In the North Island, SH2 Waioweka Gorge was pre-emptively closed from 6pm last night until further notice. Drivers were asked to delay their journey or face a long detour via SH30 and SH5, NZTA said.
Forecasters warned yesterday that thunderstorms in Coromandel and Bay of Plenty could bring brief, intense bursts of rain today, with downfalls reaching up to 40mm an hour.
For Auckland, heavy rain was expected to ease this morning, although showers were likely.
Taupō, Waitomo, and Taumarunui were also in the firing line for possible localised downpours and thunderstorms this morning.
Further east, showers are likely to hover about Rotorua and Bay of Plenty until the afternoon, before the weather system exits New Zealand by evening, MetService meteorologist Michael Pawley said.
Motorists are being urged to take care, with brief periods of intense rain capable of causing surface flooding, reduced visibility and hazardous driving conditions.
Strong northerlies are expected in Wellington this morning, with rain, heavy at times, easing to showers during the afternoon.
For the upper South Island, affected by “gumboot-height” rain, road closures and power outages yesterday, conditions are expected to improve.
Rain should ease this morning, with fine spells later in the day.
Golden Bay was among the hardest-hit regions, recording close to 300mm of rain in the 24 hours to 9am yesterday.
The West Coast is also expected to see improving weather as the system moves away.
Despite the widespread soaking, MetService said some regions just experienced their driest May on record.
Christchurch recorded only 5.6mm of rain during the month, well below the previous May record low of 11.2mm set in 2012.
Pawley said a ridge of high pressure is forecast to bring a brief period of more settled weather from midweek.
However, MetService was already monitoring another rain-bearing system approaching from the Tasman Sea later this week.
“It’s something to keep an eye on,” he said.
