The majority of London's restaurants and takeaways are feeding sewer-clotting "fatbergs" by letting grease, oil and scraps slide down their waste systems. Thames Water visited hundreds of food outlets in the capital and found nine in ten had no system for dealing with the excess gunk.
Thames Water spends around a million pounds a month cleaning sewers and says its findings are staggering. On Whitechapel Road, where a 130-tonne blockage was recently discovered, it was discovered that no restaurants had a working grease-trap.
Fatbergs are caused by oil, fat and grease merging with wet wipes and other unflushable products. Thames Water says it is funding a PhD student to study the fatty formations, including looking at ways to turn the waste into renewable energy.