A campervan crosses the Silverstream ford after leaving the Whare Flat Folk Festival at the Waiora Scout Camp, North Taieri, on Saturday. Photo / Otago Daily Times
Some South Island residents are waking up to contaminated water supplies and "overwhelmed" wastewater systems - meaning no toilet flushing - after a night of heavy rain.
And there's more to come today.
Thunderstorms in parts of the lower South Island sparked flooding and slips that closed state highways and caused havoc for holidaymakers.
Sandbag stations were opened in Dunedin, and Queenstown had collected almost 18mm of rain between midnight and 6am today.
Just after 6am, authorities issued a new warning for the Otago area.
"The heavy rain continuing through the night may have caused the wastewater system to be overwhelmed in places and there may be overflows onto roads," the Dunedin City Council said.
"People should stay out of any floodwaters and treat them as contaminated."
Before 9am, a second warning was issued for drivers to proceed with caution on Otago roads.
"Holidaymakers planning to return home, or resume their vacation and travel further in Otago today are advised to check road conditions before they set out," Emergency Management Otago group controller Matt Alley said.
"Three state highways remain closed in the region as of 8am, with numerous local roads also affected by surface flooding, slips, washouts and debris."
Alley said MetService had cancelled the heavy rain warning for coastal Otago, though rain was forecast to continue through the day, and had also assessed there is a moderate risk of thunderstorms this afternoon that could cause localised downpours and flash flooding.
Alley had been in touch through the night with the Otago Regional Council's flood warning team, who are monitoring the impact on several rivers in the Central Otago, Clutha and Dunedin districts, and with local councils about the effects on their services and roads.
"As well as roading issues, some councils had also issued boil water notices for communities whose water supplies had been affected by the flooding," he said.
"As people look to resume their travels this morning, we recommend they check the roading conditions before they leave, respect all road closure signs and detours, and allow extra time to navigate their way to their destination."
Festival-goers stranded
Two hundred people are stranded after the rising water of Silverstream cut off the Whare Flat Folk Festival, northwest of Dunedin yesterday.
Festival organiser Kathryn Olcott said the ford in Silverstream Valley Rd was closed and festival-goers at the site would be unable to leave until this morning.
She could not say exactly how many people remained at the festival.
Some festival-goers managed to get out before the ford was closed shortly after midday yesterday.
The festival's final night of performances would go ahead today, she said.
Don't flush toilets
Overnight, residents in Middlemarch were advised not to flush their toilets and avoid drinking water from bores as it was likely to be contaminated.
The Dunedin City Council advised earlier this morning that residents and visitors to the area should take care.
"With the inclement weather, the wastewater system has been overwhelmed and we would ask that you refrain from flushing your toilet until further notice," a notice said.
"Extensive flooding and wastewater surcharges have affected Middlemarch and residents are being advised not to drink water from bores unless they treat the water with a filter or similar as it is likely to be contaminated."
Water would be available from a tanker beside the Strath-Taieri Community Centre from about midday today and people were advised to bring clean containers to fill.
"Sandbags will also be available at this location," a council spokesperson said.
"The overflows are contained on roads, but people should stay out of floodwaters in these areas and treat them as contaminated."
People in the southern area were also being told to "avoid travel on the roads unless absolutely necessary".
Campers in parts of the lower South Island were warned to move to higher ground, while those in Otago planning to start the commute home were urged to delay their travel until today.
Weather forecasts for around NZ
This morning MetService said it also been a wet night in eastern Bay of Plenty with heavy showers and thunderstorms - and Whakatāne has already racked up more than 40mm since midnight, with more on the way.
Today the North Island can expect more showers, some heavy, with thunderstorms, hail and downpours possible, mainly this afternoon and evening.
In Horowhenua to Wellington, there will be cloudy periods with a few showers, some heavy, about the Kapiti Coast until evening.
Marlborough and Nelson can expect cloudy periods with isolated showers about the ranges and there will be rain with heavy falls and thunderstorms possible, easing to showers this evening in Buller and Westland.
In Canterbury, the rain continues.
"A few showers, with thunderstorms possible, mainly this afternoon and evening," a MetService spokesperson said.
"Downpours and hail possible south of Timaru from this afternoon."
Otago, Southland and Fiordland will continue to be wet and wild with periods of rain, heavy at times, along with thunderstorms, downpours and possible hail.
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