Cities turn to tech to keep sewers free of fatbergs

Swaddled in wet wipes, ensconced in congealed cooking grease and able to transform into pipe-blocking masses so hard as to require excavation equipment to dislodge, fatbergs are truly the bean-and-cheese burritos of the sewage world. They can cause havoc on a town’s bowels, achieving lengths that outspan bridges and accumulating masses that dwarf double-deckers. Fatbergs are a modern problem that have civil engineers increasingly turning to tech in order to keep their cities’ subterranean bits clear of greasy obstructions.

Fatbergs — a portmanteau of fat and iceberg — are a relatively recent but fast-growing problem in the world’s sewers. They form when FOG (fats, oil, grease) poured down drains comes in contact with calcium, phosphorus and sodium to create a hard, soap-like material. This calcium soap then accumulates on non degradable flushed items like wet wipes, sanitary pads, condoms, dental floss, clumps of hair, chunks of food waste, and diapers as they travel through a municipal waste disposal system. Though their components may start off soft and pliable (albeit damp) once ‘bergified, they harden into a mass tougher than concrete, requiring sanitation workers to employ high-pressure water jets, shovels and pickaxes in order to break it up.

“These huge, solid masses can block the sewers, causing sewage to back up through drains, plugholes and toilets,” Anna Boyles, operations manager at Thames Water, told RICS in October. “It can take our teams days, sometimes weeks, to remove them.”

7 minutes

www.engadget.com/cities-and-utilities-turn-to-tech-in-fight-against-fatbergs-160044311.html