South West Water Pleads Guilty Over Devon Drinking Water Contamination

South West Water (SWW) has admitted supplying water unfit for human consumption following a parasitic outbreak in Devon last year

The case was brought by the Drinking Water Inspectorate (DWI) after more than 140 confirmed cases of cryptosporidium were linked to contaminated water in and around Brixham in May 2024. Four people required hospital treatment as a result of the outbreak.

Roughly 16,000 households were initially told not to drink tap water unless it had been boiled. The company entered its guilty plea under the Water Industry Act 1991 at Exeter Magistrates' Court and will be sentenced at a later date.

The outbreak occurred shortly before the May Bank Holiday, significantly affecting the local tourism economy. The first confirmed cases were announced on 14 May 2024 by the UK Health Security Agency (UKHSA). At that time, SWW had reassured customers that the water supply was safe.

However, a day later the company confirmed that traces of cryptosporidium had been detected in the network and issued a boil water notice to thousands of homes and businesses in the Brixham area.

For some properties, the boil water advisory remained in place for 54 days before being lifted on 8 July. SWW previously indicated that a damaged air valve on private land was believed to have caused the contamination.

The company’s parent firm, Pennon Group, said the incident resulted in costs of nearly £40m. Customers affected by the restrictions, as well as those who became ill, were offered compensation.

The DWI requested that sentencing be referred to the Crown Court, arguing the case was high-profile and could warrant tougher penalties. However, SWW’s legal team said the company had pleaded guilty at the earliest opportunity and that the matter could be handled by magistrates.

The utility now faces a fine when it is sentenced at the magistrates’ court on 2 June.

Responding to the guilty plea, Caroline Voaden, MP for South Devon, said the admission had been “a long time coming” and criticised what she described as serious failures by the company.

She said the incident highlighted wider problems within the water industry, accusing firms of failing to match promises with action. She also urged the government to accelerate reforms, referencing previous commitments to abolish Ofwat and strengthen regulation.

Water Minister Emma Hardy described drinking water contamination as rare but “utterly unacceptable”. She said affected communities in Brixham deserved answers and called the guilty plea an important step toward accountability.

Marcus Rink, chief inspector of the DWI, said the plea reflected the seriousness of the failings uncovered during the investigation. He noted that while such incidents are uncommon, the outbreak had a major impact on the public and wider community, and that sentencing would now be decided by the court.

In a statement after the hearing, SWW repeated its “full and unreserved apology” for the 2024 incident and said it had cooperated fully with investigators. The company added that it would continue to support the legal process.