East Otago residents may be able to drink their tap water again by the end of the month after lead level spikes triggered a do not drink notice in early February.
Photo: RNZ / Dom Thomas
Residents in Waikouaiti, Karitane and Hawksbury were told not to drink their tap water or use it for food preparation or cooking.
Instead they have been relying on taking their drinking water from tankers after spikes in lead levels were found intermittently in the reticulated supply from July last year.
The highest level detected was close to 40 times the acceptable limit of 0.01micrograms/L in December.
Dunedin City Council 3 Waters group manager Tom Dyer said the council was working with Public Health Sound to lift the notice by the end of June but that might be extended to early July.
That decision would require all parties to be confident that restoring the supply wouldn't put any communities at risk, he said.
"We are also continuing to sample daily at some sites, and weekly at others, and have had no further readings above acceptable levels."
Work to replace drinking water pipes in Edinburgh Street and surrounding streets is due to be finished later this month.
Pipes had been laid above ground on some side streets as an interim measure to ensure safe water was available as soon as possible, Dyer said.
They are expected to be buried next month.
"The pipe work will remove old lead fittings in the original pipes as one possible source of contamination."
About 400 people gathered at the East Otago Events Centre to hear the results of more than 1500 blood tests carried out in the wake of revelations concerning levels of lead had been detected in the area's water supply since late July. Photo: RNZ / Tim Brown
Investigation into other possible sources are ongoing.
The council is in the early stages of development and design of the Waikouaiti water treatment plant upgrade with expectations that work will start the middle of next year and completed by early 2023.
An independent reviewer will be appointed by the council once the water supply is returned.
Southern District Health Board medical officer of health Dr Susan Jack confirmed the DHB was working closely with the council to ensure the water supply was safe.
"This week we are having meetings with the DCC and actively working on assessing the situation and mitigation measures," Dr Jack said.
"Once these measures are fully in place the 'do not drink' notice will be able to be lifted."
The DHB did not respond to questions what the measures entailed or what criteria would need to be met before the water supply can be restored.
It also did not clarify what health advice or support is being provided to the affected communities or what assurances the DHB would offer residents about the water supply when it is restored.