Between a block and a hard place

Thames Water has been forced to tackle a whale-sized blockage under the streets of Islington after discovering an industrial amount of solidified cement plugging three Victorian sewers.

Thames staff will have to manually chip away at the rock-hard mass of at least 100 metres long and weighing 105 tonnes, at a cost of “at least several hundred thousand pounds”.

Alex Saunders, Thames Water operations manager, said: “Normally blockages are caused by fat, oil and wet wipes building up in the sewer but unfortunately in this case it’s rock-hard concrete… This is not the first time damage has been caused by people pouring concrete into our sewers but it’s certainly the worst we’ve seen.”

Thames has launched an investigation into how the concrete got into the sewer with a view to recovering costs.