The Hawke's Bay Regional Council should not be doing its own investigation into Havelock North's water bores because it can't be objective, Hastings District mayor Lawrence Yule says.
The Hawke's Bay Regional Council is investigating whether Havelock North's bores were sealed properly. Photo: RNZ / Rebekah Parsons-King
The regional council has launched a formal investigation into the contamination of the town's water supply, including whether its water bores were sealed properly.
It said well samples suggested surface water had somehow infiltrated the supply.
Lawrence Yule Photo: RNZ / Cole Eastham-Farrelly
The government has already begun a separate inquiry into the contamination disaster, in which an estimated 4700 people - about a third of the town - were hit by gastric illness.
Interim test results have found the camylobacter in the water was most likely to have come from ruminant animals such as cattle, sheep or deer.
Mr Yule told Checkpoint with John Campbell the regional council was not the right organisation to do the investigation because it had a "massive conflict".
"They are responsible for the aquifer and the quality of the groundwater and the issuing of all the consents.
"So how can they objectively test our bores when they have a vested interest in proving that it's either us, or not them?"
"You have to ask the question, is the regional council the right body to be investigate our bores?" - Hastings District mayor Lawrence Yule
However, earlier today, Hastings District Council chief executive Ross McLeod said the investigation indicated the regional council was doing its job.
"This is certainly something that needs to be investigated," he said.
"It was on our list to have it done and have it done by people other than ourselves, so there's a degree of public confidence around it."
He said the bores had been up to standard in previous inspections, and the council remained confident contaminated water did not enter the aquifer via the bore casings.
Bores' seals to be checked
The Hawke's Bay Regional Council said it would investigate whether Havelock North's water bores breached their resource consent.
It said that, since the crisis began a fortnight ago, its investigation had increasingly indicated the contamination source could relate to the security of the bores.
It released a report that indicated well samples from the Brookvale Road bores contained water less than one year old.
The regional council's acting chief executive, Liz Lambert, said that would indicate surface water had infiltrated the town's water supply.
"That means that we need to take a closer look at what's actually going on because it's really what has, I guess, rung the alarm bell for us and hence is the reason for this action."
Ms Lambert said it was still a mystery how the surface water entered the aquifer.
The regional council has also accused the district council of failing to bring all the relevant information to its attention in a timely fashion.
Havelock North reservoirs drained
The Hastings District Council, meanwhile, has started draining water reservoirs in Havelock North in response to the problems.
It has closed the Tainui Reserve, and has begun draining the reservoirs on Hikanui Drive.
The flow of water had caused some minor damage to pathways and drains, but they would be repaired once the work was complete, it said.