Methven’s new $10m water treatment plant has opened, bringing "an end to boil water notices".

Methven Community Board chairperson Kelvin Holmes said at the official opening of the plant on Friday that it “should be the last of our boil water notices” that have plagued the town.

Ashburton District mayor Neil Brown went a step further.

“Kelvin said 'should'. I’ll say it will bring an end to the boil water notices.”

Methven resident and deputy mayor Liz McMillan will be looking forward to her phone staying quiet next time it rains, Brown said.

The plant became operational on September 21 and passed its first test when bad weather hit that weekend, Brown said.

“The plant worked very well responding to the dirtier water that was coming in, and we didn’t have a boil water notice out the other end.”

It is a landmark project for the community, providing a state-of-the-art facility to serve the Methven and Methven-Springfield water supplies, Brown said.

Through an elaborate series of membranes the plant filters 99.9 percent of the micro contaminants, and water is also disinfected with UV treatment, Brown said.

Methven's water supply is also fluoridated.

The site has two water sources and two reservoir tanks holding a combined capacity of 1140 cubic metres to help manage peak demand on Methven’s drinking water scheme.

Te Runanga o Arowhenua ūpoko, Te Wera King blessed the site using ‘Marty the membrane’, an example piece of the membrane, the Mauri stone for the blessing.

“This thing represents the purpose of what this whole place is about- keeping the water clean for the people, better known as te mana o te wai,” King said.

After the blessing, councillors, community board members, council staff and contractors examined the finished facility.

A public open day is being held today [Saturday] from 9am until midday.

A similar, smaller membrane plant for the Mayfield water supply is under construction and due to be operational by May 2024.

By Jonathan Leask