At Ōhakea 105 homes were identified as being in the contaminated area. Photo / Bevan Conley
Ōhakea residents have drinkable water again following the discovery of PFAS contamination in 2017.
The Ōhakea Rural Water Scheme was initiated following the discovery of the contaminant, caused by firefighting chemicals used at the Ōhakea Air Force base.
PFAS is a group of chemical compounds known as per- and poly-fluoroalkyl substances.
They are man-made chemicals that have been used since the 1950s and do not break down.
Manawatū District Council communications adviser Ben Caldwell said 105 properties were identified as being within the PFAS plume area when the contamination was first discovered.
"Council have assisted and supported the residents located in the plume area since the discovery of PFAS contamination and we're very pleased to open this scheme. Residents can be assured that they have safe and clean drinking water now," Caldwell said.
The project design started in September 2020 and was a collaboration between the Ministry for the Environment, NZDF, Horizons Regional Council, iwi Ngāti Parewahawaha and Manawatū District Council.
The work included the construction of a new bore, reservoir and water treatment plant in Sanson, as well as a 28 kilometre pipe network connecting the treated water to the affected houses and farms.
The new bore is next to Sanson School and is 620 metres deep, making it the deepest bore in the district.
It has connections to 97 properties and the ability to supply 1500 cubic metres of water a day through the treatment plant, with a capacity to hold up to one million litres of water in the reservoir.
The Government contributed $10.88 million to the project, with an extra $2 million of funding coming from the Manawatū District Council.
The NZDF contributed $5 million towards the water scheme, and as the largest customer of the water scheme, RNZAF Base Ōhakea will also cover a large proportion of its operational costs.
Ōhakea resident Andy Russell said despite the delays, it was a huge relief to have the water flowing and drinkable.
Russell chaired the committee that was set up to advocate for those impacted by the contamination.
"While the PFAS contamination is still in the shallow aquifer and will be for many years, the water scheme has lessened the community's fears around their personal health and the health of their land and production," he said.
The water scheme was due to be operational from March 2022, but progress on the scheme was "thwarted somewhat" by the second Level 4 lockdown in August 2021, Manawatū district Mayor Helen Worboys said.
"Under government guidelines, work was able to continue during this lockdown, but the increased restrictions and supply chain pressures did contribute to delays in the construction," she said.
"There was also a delay following water sampling of the aquifer, which showed that the water had a high level of iron and manganese," she said.
It was determined that a second filtration system would be required to make the water potable for consumption, which was what the council funding went towards.
In her speech at the opening ceremony, Worboys said that the community and mana whenua had been a huge consideration when designing the scheme back in September 2020, and their support and ideas had been instrumental.
"A key success has been the efforts made by the project team to reach everyone in the community who was eligible to receive water under the planned scheme.
"Face-to-face visits with residents helped with details like where tanks should go, and how many units were needed.
Meanwhile, Fire and Emergency New Zealand (FENZ) response capability manager Paul Turner said all Class-B foam brands containing PFAS compounds that had not been tested and confirmed as PFOS and PFOA-free had been withdrawn from service.
"95 per cent of Fire and Emergency's current foam use is Class-A foam, which does not contain fluorine," Turner said.
"Class-A foams are primarily wetting agents and do not contain PFAS, and are mainly used for vegetation fires."
He said FENZ continues to use small amounts of Class-B foams containing other PFAS compounds to put out fires involving flammable liquids such as petrol, but expected to have them replaced with a new fluorine-free alternative by Christmas.