British engineers are working to rid a Victorian-era sewer tunnel in London of a “monster” fatberg as heavy as 11 double-decker buses.

The 250-metre-long fatberg – a mass of congealed fat, wet wipes, nappies and condoms – is as hard as concrete and Thames Water officials said it was likely to take three weeks to dissolve.

Eight workers are using high-powered jet hoses to break up the fatberg in Whitechapel before sucking it out into tankers for disposal at a recycling site.

“It’s a total monster and taking a lot of manpower and machinery to remove,” Thames Water’s head of waste networks Matt Rimmer said.
“It’s one of the largest we’ve ever seen. It’s basically like trying to break up concrete.”

Thames Water spends about 1 million pounds ($1.6 million) a month clearing blockages on its sewer network in London and the Thames Valley.

It is appealing to its customers to avoid contributing to fatbergs with a campaign called “bin it — don’t block it”.

“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,” he said.

The company stressed sanitary products and cooking fats needed to be disposed of alongside other household waste, rather than flushed into the sewage system.

Four years ago, a similar but smaller fatberg was found in a sewer in Kingston, south-west of London, after local residents in the well-to-do suburb complained their toilets would not flush.

Last year crews used a crane to remove a seven-metre “snake” of mainly wet wipes, weighing about 750 kilograms, from a sewer under Newcastle, while another 300 kilograms were removed by crew members using buckets.

Aussie fatberg war

The Australian Competition and Consumer Commission in December initiated a world first suit in the Federal Court as sewerage authorities struggle with the “flushable” wipes it alleged do not degrade as quickly as promised. 

Fatbergs are the scourge of Australian waterways. Photo: Sydney Water.

The allegations were against Pental, which makes the White King brand of bathroom cleaning products, and Kimberly-Clark Australia, which produces hygiene wipes under the Kleenex brand.

“These products did not, for example, disintegrate like toilet paper when flushed,” ACCC chairman Rod Sims said in a statement.

“Australian water authorities face significant problems when non-suitable products are flushed down the toilet as they contribute to blockages to household and municipal sewerage systems.”

– With agencies