Several Auckland suburbs have been issued a boil water notice following possible E coli bacteria contamination. An explainer details the health implications of E coli and what the notice means for residents.

Watercare has issued a boil water notice for multiple Auckland suburbs due to an E. coli alert.

Reviews have found that faulty alarm and surge protection systems led to the Mahurangi River wastewater spill last October, for which Watercare has taken responsibility. Nine oyster farms are being compensated a total of $2.75 million by Watercare following the contamination, which forced farmers to dump thousands of oysters.