A FATBERG MEASURING the length of a Boeing 747 has been found in a sewer under a London street.

The fatberg, which is a congealed mass of fat, wet wipes, and litter put down drains and toilets, measured more than 80 metres. It took a team of experts almost one week to break it up.

“We’ve found all sorts in this sewer – from tennis balls to planks of wood,” said Dave Dennis of Thames Water. “It goes without saying they shouldn’t be in those pipes”.

The photograph (above) shows how the collection of fat and wet wipes almost reached the top of the sewer.

Dennis described how solid waste hardens when things are incorrectly put down drains and toilets.

“Fat goes down the drain easily enough, but when it hits the cold sewers, it hardens into disgusting fatbergs that block pipes”.

Wet wipes cling to the fat. Fat clings to the wipes. And pretty soon your fatberg is out of control and sewage is backing up into roads, gardens and in the worst cases, flooding up through toilets and into homes.

The experts used high powered water jets to break up the congealed mass to allow waste water to pass through the sewer again and prevent flooding at homes and businesses in the area of Shepherd’s Bush in west London.

The equivalent of €15 million is spent in London every year tackling blockages caused by people pouring cooking oil down the drain and wet wipes down the toilet.

Read: 14-tonne ‘fatberg’ discovered in London sewers >