Buller District Council has lifted a 'boil water' notice for Reefton residents after tests showed the town reservoir is clear of E coli bacteria.
The council today apologised to residents for the inconvenience caused by the notice but said its first priority was to ensure public health and safety.
It also gave an assurance it would look at bringing forward projects to solve the recurring problem.
Last week's positive E coli test was at the reservoir only and not throughout the reticulation system, the council said.
"We are investigating the source (of the bacteria) and will implement short-term control measures including temporary chlorine dosing at the reservoir."
The council said it would also look at speeding up a more permanent solution to the recurring water problem.
"Even though this boil water notice has been lifted, and the previous one for Reefton was nearly a year ago, we take these events very seriously. We will examine acceleration options of our asset renewal programme to reduce likelihood of future occurrences," a council spokesperson said in a statement.
Key projects included replacing the 80-year-old pipeline from The Strand treatment plant to the elevated treated water storage tanks, and upgrading them to reduce recontamination risk and treated water loss, the council said.
"Any system upgrade will also consider future legislation changes and mandatory compliance requirements for all water supplies across New Zealand."
Reducing recontamination risk would ensure a safer, more reliable drinking water supply for Reefton.
"We are engaging with Community and Public Health regarding upgrade options and timeframes. We also acknowledge the community consultation steps and ultimately council resolution before any long-term solutions can be decided."
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