fatberg

thumb|A dried section of the Whitechapel fatberg, on display at the Museum of London

A fatberg is a rock-like mass of waste matter in a sewer system formed by the combination of flushed non-biodegradable solids (such as wet wipes) with fat, oil, and grease (FOG) deposits. The handling of FOG waste and the buildup of its deposits are a long-standing problem in waste management, with "fatberg" a more recent neologism. Fatbergs have formed in sewers worldwide, with the rise in usage of disposable (so-called "flushable") wet wipes. Several prominent examples were discovered in the 2010s in Great Britain, their formation accelerated by aging Victorian sewers. Fatbergs are costly to remove, and they have given rise to public awareness campaigns about flushable waste.