Patea residents are warned to boil their water after tests revealed E. coli in the water supply.
"Routine tests have detected the bacteria Escherichia coli, known as E. coli, in the Patea Water Supply, and investigations are now under way to find the source," South Taranaki District Council water supply manager Peter Cook said in a statement.
Mr Cook advised residents to boil all water used for drinking, brushing teeth, or for food preparation until further notice.
Bringing water to the boil is enough to kill all bugs, however the council recommends boiling the water for about a minute, he said.
"The council has started chlorinating the supply to kill all bugs. You will notice a difference in the taste and odour over the next couple of days.
"Chilling the water in your fridge can reduce the chlorine taste," Mr Cook said.
"As a precaution, your water still needs to be boiled even if the smell or taste of chlorine is present."
Anyone feeling sick should visit their doctor as soon as possible.
Council is in regular contact with the Taranaki District Health Board and is taking advice for precautionary measures.
Further information and updates on the situation can be found on the council's website, www.southtaranaki.com or by calling 0800 111 323.