The innovators: a new U-bend to prevent the buildup of fatbergs in sewers

(Photo: Martin Godwin/the Guardian)
It was two years ago when the residents of a block of flats in Kingston upon Thames complained of difficulty in flushing their toilets that the alarm was first raised. The problem turned out to be a 15-tonne mass of congealed grease and oil - a fatberg - that had blocked 95% of a 2.4-metre diameter brick pipe in the main sewer, threatening to turn the London borough into a cesspit.»