South West Water was fined £1.853 million - a record fine for a drinking water offence – at Exeter Magistrates’ Court yesterday and ordered to pay £75,000 following a prosecution by the Drinking Water Inspectorate for drinking water failures.

The Pennon-owned water company pleaded guilty at an earlier hearing in March to an offence under section 70(1) of the Water Industry Act 1991.that led to a Cryptosporidium outbreak in the Brixham area of Devon.

Between 15 May and 8 July 2024, up to 39,000 consumers were subject to a boil water notice following the detection of Cryptosporidium in the drinking water supply. Over 390 customer contacts reporting illness were received by South West Water during the incident.

The Inspectorate’s investigation found that Cryptosporidium from animal faeces had entered the drinking water supply network on agricultural land likely via an exposed and faulty air valve covered in mud. Soil samples taken in the vicinity of the air valve contained Cryptosporidium oocysts whose DNA matched the Brixham strain of the illness. The case is the first prosecution under section 70 of the Water Industry Act 1991 involving Cryptosporidium with confirmed consumer illness in over a decade.

Following the incident, South West Water carried out extensive work to make the water supply safe. This included flushing the network and a specialist deep-clean of the water mains, as well as installing permanent ultraviolet disinfection and fine filtration systems at the two service reservoirs supplying the Brixham area – safeguards that remain in place today.

The Inspectorate also carried out an industry-wide review of how to inspect and maintain air valves across their networks and issued South West Water with a formal legal notice requiring improvements to its air valve risk management.

The Inspectorate will be publishing its findings and conclusions to the event shortly.

Marcus Rink, Chief Inspector of the Drinking Water Inspectorate said:

“This was a major event which had severe consequences for the local community and visitors to the area.

“Thankfully such events are extremely rare, and the UK is one of the countries with the highest drinking water quality in the world. Consumers across England and Wales should continue to have confidence in their drinking water supply.

“It is right that South West Water pleaded guilty to this offence and has been held accountable. The court has considered the evidence from my inspectors’ thorough investigation and rightly recognised the harm this incident caused. Today’s outcome demonstrates that when failings occur, there will be serious consequences.”