Long before trashy B-movies about alligators in sewers, shark invasions, rampaging killer sheep, and killer garden slugs (yes, they have all been made), there was a very real fear in London of subterranean farming livestock ready to unleash hell on the city dwellers.
Around the 1850’s many lived in fear of terrifying pigs living in London’s sewers. It was believed that, at any time, herds of super stinking sewer swine would make a break for it and run riot.

This harrowing sub-Stephen King chiller scenario, like so much else, was born of Chinese whispers…

Construction stage

Someone had managed to put it about that a pig (presumably two) had escaped to the sewers and, over a number of years, been fed on all manner of dreadful waste and developed a pretty serious attitude problem. They had subsequently produced sewer fed offspring and the whole tribe was ready to take its terrible retribution on a cruel city.

Abbey Mill pumping station
It did not help that this story was given credence by being mentioned in The Daily Telegraph editorial in 1859.
Sewers are not an exciting or enticing proposition to this day, but thanks to Joseph Bazalgette and his remarkable engineering feat in creating the 1,100 miles of ‘modern’ street sewers they are considerably better than in the days of pig fearing folk.

The city was growing at speed, sewage systems, such as they were, did not keep up, The Thames was basically a large open sewer and cholera was rife. Angry porkers who’d only ever known the grimmest life in the foul and fetid underworld was genuinely the stuff of horror stories…