UK Water News: June 2026

A mixed fortnight for UK water. The largest survey yet of PFAS in a UK city found London’s tap water within safe limits, the government pushed back on a deal that would shield Thames Water from new fines, and forecasters renewed their warning that summer 2026 could bring restrictions. Here is what happened and what it means if you are buying a filter or softener.

Big London survey finds PFAS in tap water, but within safe limits

Researchers at Imperial College London published the largest study of its kind into PFAS, the so called forever chemicals, in a UK city’s drinking water. The work, reported on 12 May in Environmental Science: Advances, found PFAS were present in samples from homes and public fountains across London, but always well below the Drinking Water Inspectorate thresholds: under the 10 nanograms per litre Tier 1 limit for individual PFAS and inside the 100 nanograms per litre total. For most households this is reassuring rather than alarming. If you still want to reduce PFAS at the tap, the technologies that actually do it are activated carbon block and reverse osmosis, not a basic jug; our RO vs jug vs under-sink comparison covers what each one removes. The findings are summarised in the Imperial College London announcement.

Government pushes back on a deal that would spare Thames Water new fines

The Environment Secretary has written to Ofwat cautioning against a rescue proposal from Thames Water’s creditors, a roughly £10 billion cash injection in return for new sewage fines being waived for around four years. The letter argues the offer would put an “undue burden” on the company’s 16 million customers, while Thames Water remains under about £20 billion of debt and faces the prospect of special administration. None of this changes water quality at the tap day to day, but it is a reminder that the network failures worth planning for are rare contamination events, not the everyday supply: a properly certified under-sink or RO system is what handles those. The dispute is covered by The Canary.

Forecasters warn summer 2026 could bring early restrictions

After the driest spring on record in 2025 and a slow winter recovery, water companies and drought planners have flagged that summer 2026 carries an elevated risk of temporary use bans, with the South East singled out as the highest risk region. South East Water has said its Ardingly reservoir may not fully recover even with a wet winter, and fourteen companies were still in formal drought or prolonged dry weather status earlier this year, as reported by Utility Week. A hosepipe ban does not affect drinking water quality, but heavy summer demand and chalk groundwater are why the South East has some of the hardest water in the country; if you are unsure where yours sits, run your postcode through our UK water hardness checker.