The company has emphasised that the issue is isolated to a single property and that the drinking water in the area remains safe.
The issue was initially reported by The Guardian, which highlighted that a notice had been sent to the affected property advising precautionary measures, including boiling water before use and bleaching taps and sinks.
Thames Water has since clarified that this advice applies only to the single impacted property and not the wider community.
Thames Water stated that comprehensive testing of surrounding properties has shown no traces of E coli, and customers can continue to use and drink their tap water as normal.
For the single impacted property, Thames Water has issued boil water advice as a precaution while investigations continue.
Bottled water has been provided to the affected resident, and the company is assisting with flushing the taps to resolve the issue.
Initial findings suggest that the contamination is likely due to internal plumbing or the tap itself, rather than the wider water supply.
E coli is a bacterial infection that can cause stomach cramps, diarrhoea, and fever, but Thames Water has confirmed there is no broader risk to public health.
A spokesperson for Thames Water said: “We are aware of a report by The Guardian which states E coli has been found in the water supply in an area of South East London.
“We would like to reassure all our customers that the issue is isolated to a single property. As part of our normal process, we have tested surrounding properties and all other sample results were clear with no E. Coli found.
“There are no concerns surrounding the quality of drinking water in the area and customers can continue to use and drink their tap water as normal.
“For the impacted one property – we have issued boil water advice while investigations are ongoing. To reiterate there are no concerns surrounding the quality of our drinking water in the area and this issue is isolated to a single property.
“We have taken swift action and will continue to test over the coming days as part of our regular process.
“We take the quality of our water extremely seriously – it is amongst the highest quality drinking water in the world – and since 2010 more than 99.95% of tests taken from customers’ taps met the standard required by UK legislation.
“Every year we carry out more than 500,000 tests, taking samples from source to tap.”
