London’s sewers are rich with surprises. Utility has reported the quantity of garbage present in the sewerage system, including a 130 ton ‘fatberg’ and 115 tons of hardened concrete. People usually flush not only the three Ps (pee, poo, and toilet paper) down the toilet, but also concretebergs, oil, toiletries, wipes, and other substances and products. This kind of material can obviously block the entire system, so Thames Water engineers spent almost 11,000 hours cleaning, using high-pressure water jets in more than 900 kilometres of sewers.

In the past year, they scrubbed 183 metric tons of materials, a quantity that could fill an entire Boeing 747 passenger jet – the hardest job was under Waterloo Road, where they found 100 metric tons of unwanted garbage. Thames Water has launched a new campaign entitled ‘Bin it, don’t block it’ to instruct Londoners on how to use their toilets and to forbid the disposal of materials different from organic waste.