30-tonne fatberg removed from sewers under Borough Market

Stephen Pattenden, Thames Water network manager, said: "Fatbergs are like monsters from the deep, lurking and growing under our feet, and the team worked around the clock to defeat these two before they could cause damage to our customers or the environment.

"We've all seen the problems and damage they cause, and I'd therefore ask everyone to please make sure they don't pour fats and oils down the sink. By letting the fat cool, putting it in a proper container like a glass jar and then in the bin stops a fatberg growing into a monster."

Thames Water has just launched a campaign asking people to think about what they put down the drain, calling on them to be 'Everyday Sewper Heroes'. By making sure unflushables such as cooking fat, oil and grease, plastic wipes and cotton buds are binned means everyone is fighting the fatberg.

Stephen added: "Fatbergs are a vivid reminder to us all that out of sight is not gone forever, and each year we have to deal with 75,000 blockages across our network at a cost of £18 million. Many of these could easily be avoided.

"It's an extremely difficult job getting them out of our sewers. It's cramped, hot and very unpleasant, especially when a chunk of fatberg is disturbed. The smell can be overpowering. So that everyone can have a happy Christmas, please bin your fat and wipes and don't feed the fatberg."

Last year a five tonne fatberg from St George's Circus was dissected in a Channel 4 documentary.