The sub-zero overnight temperatures resulted in hundreds of calls in the past few days to plumbers to fix burst or frozen pipes.
And householders are warned to expect more such problems, with MetService yesterday predicting further frosts for the region overnight.
South Otago plumbers say they have received more than 40 callouts so far to fix burst pipes or split exhaust valves on hot water cylinders.
In Central Otago, plumbers were called to more than a dozen damaged pipes in Wanaka and 15 in Cromwell.
Some of the homes had ceilings damaged and others were flooded.
Rory McLellan, of McLellan's Ltd in Alexandra, said his firm had 50 calls yesterday morning and probably 40 on Sunday.
His advice to homeowners was to leave the manhole to the ceiling open or ajar, to allow some of the heat from the house to go into the ceiling, keeping pipes thawed.
He also suggested people learn where their water shut-off was, and pin a plan of that site to their hot water cylinder.
Dunedin City Council network operations manager Mike Ind said that in the past two days the council had dealt with eight burst pipes in the water reticulation system under roads.
Two Air New Zealand flights were delayed and one was cancelled at Dunedin International Airport yesterday.
Planes needed to be de-iced and it was not until about 9am that a flight was able to leave the airport.
Dunedin was the only centre in Otago to rise above zero by 10am, with some places, such as Queenstown and Dunedin airport still minus 7 degrees Celsius mid-morning.
Niwa climate scientist Georgina Griffiths said the lows were not record-breaking, but because the past two winters had been "quite warm" in comparison, people were feeling the cold.
"It's been the first cold spell in two years and it has been long-winded."
The closest to a record was Ranfurly, which experienced its fourth coldest morning since 1975 with its low of minus 11degC.
Dunedin airport's minus 8 degrees Celsius yesterday was the 10th coldest since 1962, according to Niwa figures.
