Methven’s water woes are on track to be solved by winter.
The Methven water supply has been hit by numerous boil water notices following heavy rain in recent years.
The solution is a $9.4 million water treatment upgrade that is set to be completed before the busy winter in the tourist town.
One of the two new reservoir tanks is already operational and the membrane plant is under construction.
Ashburton District Council group manager infrastructure Neil McCann, said the membrane treatment plant uses ultrafiltration technology, providing a barrier that removes turbidity [cloudiness] and will allow water to be treated even in a bad weather event.
“Turbidity has historically been the reason for boil water notices on the Methven and Methven-Springfield supplies, so this should see the end of them.”
The first new reservoir tank, with 840 cubic metres of storage capacity, is operational after being successfully installed in September last year.
The old concrete reservoir tank will be drained and its structural integrity investigated to see if it is still useful for storage, with that work to begin later this month, McCann said.
The second new reservoir is set to be installed before the end of February.
The original second tank was damaged beyond repair in the 150kph winds in July, and McCann said the replacement tank kit has arrived in New Zealand and is expected to be delivered next week.
“Installation will start straight away and we are aiming for the end of February for its commissioning.
“Construction of the membrane plant building started late last year, and is on target to be completed by the end of April.
“The membrane treatment equipment will then be installed.
“We aim to have the membrane plant commissioned by winter.”
The membrane plant will be switched over after a three to four  week commissioning process, McCann said.
“The switchover will take between three to five hours after commissioning has been signed off, and the existing pump station will continue supplying water during the commissioning period.”
The only issue is with the fluoridisation of the supply, and it is one of timing.
The fluoride product used in the current treatment plant is running out, and will likely run out before the new system, which uses a different product, is operational.
That leaves the council facing a window where they need a temporary, and likely expensive, option unless they are granted a dispensation by Manatū Hauora, Ministry of Health.
McCann said the Director General of Health has been informed of the council’s efforts to find alternate supplies of fluoride and they will continue to liaise with Manatū Hauora to solve the issue.

• By Jonathan Leask