Water supply disruption affects South East Water customers in Kent and Sussex

Two major water supply disruptions affected tens of thousands of South East Water customers across Kent and Sussex last winter, according to research jointly commissioned by the Consumer Council for Water (CCW) and Ofwat and published on 3 June 2026¹. The first incident, in late November and December 2025, affected around 24,000 households and businesses in Tunbridge Wells and surrounding areas; the second, in January 2026, affected potentially 69,000 properties including East Grinstead, Forest Row, Ashurst Wood, parts of Tunbridge Wells, Canterbury and Blean, and Staplehurst².

The November and December disruption followed a water quality failure at South East Water's Pembury Water Treatment Works, where treated water was too cloudy for final disinfection to be guaranteed and the treatment process shut down². A formal precautionary boil water notice was issued from 3 December 2025 and lifted on 12 December 2025; water in the network remained suitable for washing and flushing toilets but had to be boiled and cooled before drinking or cooking². The January incident involved no water, low pressure, intermittent supply and quality concerns, which the research attributes to a combination of weather-related and network resilience issues, reduced treatment capacity and freeze-thaw conditions causing multiple burst mains across Kent and Sussex; unlike the first incident, no formal boil water notice was issued².

The research found communication was the clearest and most consistent point of failure, with fewer than one in ten affected customers satisfied with how reliably information was provided about when services would be restored¹. Around seven in ten first realised there was a problem when their supply stopped or pressure dropped, or through word of mouth and local Facebook or WhatsApp groups¹. On safe drinking water, 26% of customers affected in November and December 2025, rising to 41% in January 2026, did not feel it was clear how to access water that was safe to drink¹. Over 40% of customers across both incidents did not believe the amount of water given out at bottled water stations was sufficient for their households' needs¹. Around half of customers on the Priority Services Register said they did not receive the support they expected¹.

Sources: CCW¹, Impact Research report for CCW and Ofwat²

Why it matters for households

The findings describe what happened to households whose supply stopped, in some cases for a fortnight: one respondent quoted in the research reported receiving a single delivery of 12 two-litre bottles of water during a 14-day outage². The research records that around half of those affected now store bottled water at home in case of future incidents¹. For households wanting to check whether an interruption is affecting their area, the guide on how to check if there is an outage in your area sets out the steps, and the supply interruption checklist covers what to have ready. The guide on how long until my supply is restored explains what companies are expected to tell customers about timescales, and how water companies respond to a major incident describes the bottled water stations and Priority Services Register support the research examines. Households planning storage can use the guidance on how much drinking water to store per person and the home drinking supply storage checklist; the household guide to water in an emergency covers the wider picture, and who checks drinking supplies explains the roles of the Drinking Water Inspectorate, Ofwat, CCW and DWQR.

What happens next

Ofwat began investigating whether South East Water had complied with its customer-focused licence obligations². CCW has held an accountability session with South East Water executives, at which customers outlined their concerns and an action plan was agreed with the company for future events, focusing on communication, support and resilience². CCW states it will continue to work with the company to strengthen its response to incidents and improve how it supports and communicates with affected customers during any future disruption¹.