Residents of the small Canterbury settlement of Governors Bay have been advised to boil their water following the discovery of E. coli in the town's water supply.
"All water that is used for drinking, food preparation, utensil washing, brushing teeth or making ice should be boiled until further notice," said Christchurch City Council Head of Three Waters and Waste John Mackie.
"We will be chlorinating the water to kill the E. coli but it is going to take a couple of days to flush the network and to get confirmation the water supply is clear of contaminants so until that happens it is important people heed the boil water notice."
Mackie said it was possible the E. coli contamination was caused by the heavy rain over Easter weekend contaminating the Hayes 2 reservoir that supplies water to parts of Governors Bay, but that was yet to be confirmed.
Until the source of the contamination was confirmed, the council and Community Public Health were taking a precautionary approach and issuing a boil water notice to the whole of Governors Bay.