Gastro: Authorities mystified by outbreak

From left: Brett Chapman, water services manager, Lawrence Yule, mayor, Jane Mackay, marketing communications manager, Dylan Stuijt, water supply manager, Hastings District Council, at a press conference. Authorities remain mystified by the outbreak. Photo / Duncan Brown

The bores at the centre of the Havelock North gastric illness outbreak have been in place 35 years without sign of contamination until the end of last week, says Hastings Mayor Lawrence Yule.

The No1 and No2 bores draw water from the Te Mata aquifer, similar to the Hastings supply drawn from the Heretaunga aquifer.

The Havelock North bores are situated in Brookvale, quickly developing as an urban area on the northern fringes of what was the Borough of Havelock North before the merger with Hastings City and Hawke's Bay County to form the Hastings District Council in the local government reform of 1989.

Yesterday, Mr Yule and other authorities remained mystified as to the cause, saying that if it's not identified Havelock North faces a future of treated supply, as had been the case since chlorine was introduced last Friday, or the "abandonment" of the Brookvale site as a water source.

Mr Yule said immediate concern was to make sure people follow the rules," he said, reiterating the need for people to boil water, wash hands and take other precautions to prevent another escalation.

"But clearly, if there is negligence by the council there will be questions asked."

The water supply across Havelock North, Hastings and Flaxmere comes from rain falling as far away as the Ruahine, Kaimanawa and Kaweka ranges, collecting in the Ngaruroro River.

The water seeps between the river gravel to be collected in the aquifers, the underground reservoirs which are the basis of Hawke's Bay's reputation of having some of the best quality water in the world.

Pumping stations across the region deliver the water from bores; in the case of the Brookvale bores from a depth of about 20 feet.

The storm which produced 125mm of rain Hastings on August 5-7, almost one-and-a-half times the area's historic August average, is considered an unlikely factor because the suspect bugs are unlikely to have survived the week before the discovery of the bacteria.

None were detected in routine tests on Tuesday last week.

The regional council's role was to assess resource consent applications to extract water from aquifer.

It had no other day-to-day involvement in the supply.

However since the outbreak, regional council chairman Fenton Wilson said it had been "filling in gaps", and lending its assistance to Hastings District Council.

Since yesterday, it had been testing other bores in the affected areas.

"We're throwing our scientific weight behind what those guys are doing," he said.

"We're working to fix this thing because that's our main aim, whoever you are, we want to get this thing tided up, and understand how it happened so we can make sure it doesn't happen again."