An inquiry looking into the water contamination crisis in Havelock North has found the local and regional councils, as well as the water assessor, failed to meet the high standard needed to keep the public safe.
Findings from stage one of the Havelock North water contamination inquiry were released on Tuesday.
About 5500 people - a third of the town's population - became ill with campylobacter when the town's water supply was contaminated in August last year.
Three deaths were linked to the outbreak and more than 40 people were hospitalised.
Inquiry chairman Lynton Stevens QC outlined the inquiry's findings at Hastings District Court on Tuesday.
He said the Hastings District Council, the Hawke's Bay Regional Council and the drinking water assessor "failed to adhere to the high standards of care necessary to protect public health and illness".
However, he added: "The inquiry has found that none of the faults directly caused the outbreak however, had all or any of these not occurred a different outcome may have resulted".
It's believed that the contamination occurred from sheep faeces getting into a bore used for drinking water following heavy rain.
Stage one of the inquiry looked into the water contamination incident and the response to it.
Stage two, which is due to be reported back in December, will address systemic issues and provide national recommendations about the water supply.