South West Water fined £1.8m over Devon parasite outbreak

South West Water has been fined almost £2m after the supply in and around Brixham, Devon, was contaminated with the parasite cryptosporidium.

Four people were hospitalised and there were more than 140 confirmed cases of sickness and diarrhoea during the 54-day incident in May 2024.

The company pleaded guilty to supplying water unfit for human consumption at an earlier hearing, offering a “full and unreserved apology”.

The utility firm was sentenced at Exeter Magistrates’ Court following a prosecution brought by the Drinking Water Inspectorate.

Judge Stuart Smith told the court it had been “a major public health incident” in which “disruption to daily life was extensive”.

He said the harm had been “wide-ranging and profound” and the system of monitoring air valves had been “inadequate”.

He said the “unvarnished reality” was there had been no visual inspection scheme of air valves which showed a “systemic failure of governance” of South West Water.

Smith said there had been mitigating factors and he had reduced the £1.853m fine by a third as the company had entered an early guilty plea.

The largest fine to be handed to a water firm to date is the £122.7m penalty water industry regulator Ofwat handed to Thames Water for breaching rules over sewage spills and shareholder payouts in May 2025.

South West Water offered those affected an “unreserved apology” and said it wanted to publicly record its “genuine remorse” for the incident.

Smith said SWW had responded rapidly once the contamination had been discovered, had deployed “substantial personnel” and provided “substantial financial remediation” to those affected.

Keith Haslett, chief executive of the Pennon Group which owns South West Water, said: “It is very clear we must learn lessons from this incident and work hard to rebuild trust with the customers and communities we serve, both in Brixham and beyond.”

What is the water parasite cryptosporidium?

The first cases of people affected by the water parasite outbreak were confirmed by the UK Health Security Agency (UKHSA) on 14 May 2024, the run-up to the May Bank Holiday.

The judge told the court: “Businesses were heavily impacted during what should have been a high season period.”

On 15 May 2024, the company confirmed traces of cryptosporidium had been found in the supply network and issued a boil water notice to about 17,000 homes and businesses in and around Brixham.

Advice not to drink tap water without boiling it remained in place for 54 days for some properties in the area, before it was finally lifted on 8 July.