Households in south-east London have been told to boil their water after E coli was found in the supply of a property.
People in properties in Brockley have been advised to boil any water they use until the results of tests conducted during visits by Thames Water are returned.
The boil water notice, seen by the Guardian, says: “The samples we have recently collected from your drinking water tap were not of the quality we would normally expect.
“We are investigating whether this may be due to an issue with our mains supply or whether this is related to your internal pipework or fittings. As a precaution we therefore advise you to boil all water before it is used for drinking, cleaning teeth, preparing food, provision of drinking water for pets.” It also recommends that taps and sinks are bleached after use.
David Bowen, a resident of one of the properties affected, told the Guardian that he was informed by Thames Water that E coli had been found in his tap water after testing conducted at the weekend. Since Saturday, he has been told to continue boiling any water he drinks.
Thames Water also tested the properties either side of his home and advised that they boil their water while they waited for results.
However, others in the area say they have had requests for testing refused.
Bowen added: “The testers refused to do any testing requested by other [more vulnerable] neighbours.”
The local Labour MP, Vicky Foxcroft, is aware. A spokesperson for her office told the Guardian: “Thames Water say they are engaging with the resident(s) and supplying them with bottled water while they investigate.”
E coli can cause serious illness including severe stomach cramps, bloody diarrhoea and vomiting.
Last year, a boil water notice was issued for tens of thousands of Devon households after the parasite cryptosporidium was found in the supply. Some homes had to boil their water before use for more than a month.
Water industry whistleblowers also recently told this newspaper that the safety of tap water in the UK could be at risk because water companies are unable to use products to clean it, as all the laboratories that test and certify the chemicals have shut down.
A Thames Water spokesperson said: “As part of our standard water quality testing that we carry out throughout the year, last week tests were undertaken at a property where traces of E coli were found. We also tested surrounding properties and no further traces were found.
“For the impacted one property – we have issued a boil water notice and have supplied the resident with bottled water while investigations are ongoing. Follow-up investigations indicated this is likely due to either contamination of the tap or internal plumbing system. We are continuing to engage with the customer providing advice on flushing the taps to bring high-quality water back into the taps.”
The Department for Environment, Food and Rural Affairs has been contacted for comment.
• This article was amended on 6 January 2025 to clarify that traces of E coli were found in the water at a single property in Brockley, though other properties were advised to boil their water as a precaution while further tests were carried out.
