The water company has been calling for a specific limit for PFAS since 2019 and says it remains “committed to playing our part in delivering it.”

The proposed new standard of 4 nanograms per litre (ng/l) would be among the strictest in the world. According to Jersey Water, it is considered by independent experts to be a “precautionary measure” to future-proof the Island’s water supply, rather than a response to any issue with the current mains drinking water supply, which remains safe to drink.

Consistently guaranteeing water quality that is at or below this limit will require treatment infrastructure that does not currently exist in Jersey, the utility says. The water company is looking at options for a new treatment facility and will most likely need to reconfigure both the untreated and treated water supply network.

In the short-term, the utility is imminently due to start full-scale trials at its Augrès treatment works for liquid powdered activated carbon (PAC). Jersey Water expects this to deliver reductions in PFAS concentrations as a potential interim solution - but to achieve the 4 ng/l limit will require investment in other treatment.

Longer-term, the company has already assessed more than ten treatment options and identified granular activated carbon (GAC) and ION exchange as the only proven, suitable technologies for Jersey. Pilot trials at its Handois treatment works will start shortly and are expected to take 12 to 18 months to verify the effectiveness of the treatment.

Once the pilot trials have completed, Jersey Water will then need to begin the process of securing the necessary funding from the Government of Jersey, followed by the technical design, site selection and acquisition, planning consent, procurement, construction and commissioning of the new treatment infrastructure, including the reconfiguration of the water supply network.

“Given the scale and complexity of this work, delivering a permanent treatment solution will be a multi-year process. The overall timeframe will be determined by the funding, regulatory, technical and delivery requirements”, the water company says.