The enormous fatberg is located under Whitechapel, London (Picture: Thames Water)

A grotesque and gargantuan fatberg has been discovered under the streets of London.

Thames Water claim it will take them weeks to remove the 130 tonne solid mass of fat, oil and waste from a 1200mm high by 700mm wide Victorian sewer in the Whitechapel area.

The fatberg is around 250 metres in length and among the biggest that workers have ever seen, a Thames Water spokesperson told Metro.co.uk that the task in front of them is ‘basically like trying to break up concrete’.

A crew of eight will use powerful jet hoses to break up the fatberg before the smaller pieces are sucked out of the sewers and into tankers which will transport them to a recycling centre.

Fatbergs are created by a build-up of fat and grease combined with sanitary products – the main cause is people pouring cooking oil down the sink and flushing nappies, sanitary towels and wipes down the toilet.

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Biggest ever fatberg 250 metres long weighing 130 tonnes discovered under London

The fatberg is 250 metres long (Picture: Thames Water)

Biggest ever fatberg 250 metres long weighing 130 tonnes discovered under London

A crew of eight will work on the fatberg (Picture: Thames Water)

Matt Rimmer, Thames Water’s head of waste networks, told Metro.co.uk: ‘This fatberg is up there with the biggest we’ve ever seen. It’s a total monster and taking a lot of manpower and machinery to remove as its set hard.

‘It’s basically like trying to break up concrete. It’s frustrating as these situations are totally avoidable and caused by fat, oil and grease being washed down sinks and wipes flushed down the loo.’

The crew are removing around 20 to 30 tonnes every shift, with work starting at 8am and continuing until 5pm seven days a week.

Biggest ever fatberg 250 metres long weighing 130 tonnes discovered under London

Fatbergs are a build-up of grease and sanitary products that clog up sewers (Picture: Thames Water)

Matt added: ‘We check our sewers routinely but these things can build up really quickly and cause big problems with flooding, as the waste gets blocked. It’s fortunate in this case that we’ve only had to close off a few parking bays to get to the sewer.

‘Often we have to shut roads entirely, which can cause widespread disruption – especially in London.’

CCTV camera inspections showed the sewer to be completely blocked by the fatberg which is 3.5 metres below ground.

Work will continue throughout September until the sewer is clear.

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