Residents in Christchurch's Mount Pleasant are being told to boil their water as a precaution.
Photo: RNZ / Cole Eastham-Farrelly
Christchurch City Council said there had been a loss of pressure in the water mains that supplied the area.
A spokesperson said this afternoon up to 300 properties were without water while contractors worked to restore supply.
Manager of technical services Will Rowson said the boil water notice would remain in place until they were confident there was no contamination.
He said the notice was a precaution as the water supply relied on a constant pressure to prevent contaminants entering pipes.