Christmas warning after 100-tonne fatberg discovered in London sewers

Extraction of the blockage could take ‘weeks to complete’, according to Thames Water

People have been warned to think about what they pour down their sinks and flush down their toilets over Christmas after a 100-tonne fatberg was discovered in London’s sewers.

The newly discovered fatberg, which is a solid mass of congealed fats, oils, grease and non-flushable waste, was found in Whitechapel, east London, and is estimated to stretch for around 100m and weigh approximately 100 tonnes.

Tim Davies, head of waste operations for north London at Thames Water, said the extraction of the blockage could take “weeks to complete”.

He added: “This latest fatberg shows exactly what happens when fats, oils and wipes go down our drains – they don’t disappear, they build up and cause serious damage. The cost of clearing blockages and repairing sewers runs into tens of millions of pounds every year, and that money ultimately comes from our customers.”

Thames Water said it could take weeks to extract the fatberg fully (Thames Water)

It has been dubbed “the grandchild” of the 2017 Whitechapel fatberg, which once weighed 130 tonnes and stretched over 250m (820ft). The 2017 fatberg was among the largest ever discovered in the city, and a sample even went on display in the Museum of London.

Thames Water has now asked people to be mindful of how they dispose of waste associated with rich cooking over Christmas.

Fat, oils and grease cause more than 20,000 blockages every year across the Thames Water network, accounting for 28 per cent of all sewer blockages.

The company said it sees a seasonal rise in blockages during December and January, with clearance costs totalling £2.1m over the two months.

Research commissioned by Thames Water has revealed that households across London and the Thames Valley are unknowingly contributing to blocked pipes, polluted waterways and increased risk of internal flooding through everyday disposable habits.

According to a recent survey, more than 40 per cent of people had poured meat juices down the sink, 39 per cent gravy, 18 per cent animal fats including lard, 28 per cent cream, 21 per cent custard and 10.5 per cent hummus – all fatty and oily substances that can congeal in pipes and block them.

Thames Water has urged people to scrape food scraps from any dirty dishes, ensure plugholes are fitted with a strainer and avoid pouring liquid foods, such as gravy or cream, down the sink.