Lessons from Parisian Sewers – Sewer balls

On a recent trip to Paris, I convinced my husband and in-laws to come with me on an adventure into the underworld. Enter the sights and sounds of the Paris Sewer Museum (Musée des Égouts de Paris). Ever since I had read about the museum in a book (‘An Underground Guide to Sewers’, but Stephen Halliday) I had wanted to go.

Tunnel cross sections in Parisian Sewers

Learning about the different tunnel cross sections used in Parisian sewers, Source: Author

Paris Sewer Museum (Musée des Égouts de Paris)

The museum is attached to a working sewer station that lets visitors explore the evolution of this hidden French infrastructure. Let’s just say, it’s a 4D experience, the fourth dimension being ‘smell’. That said, there was so much to look at and learn that the initial ‘wall’ of the odour was soon forgotten.

Picture of a sewer ball

Our first encounter with the sewer ball, Source: Author

Sewer Balls

Out of all of the things that we saw, the artefact that stood out the most were the ‘sewer balls’. The giant balls made of iron or wood were used to clear debris from the large diameter sewer tunnels.

Size of sewer ball

Me and my best mate, Source: Author

Sewer ball design

A lot of the tunnels were designed to be ‘visitable’, I.e. to provide manual access to the structure for inspection and maintenance purposes. In tunnels where this access was not provided, these ‘sewer balls’ were used, most often in siphon and outfall parts of the network. The diameter of the balls was slightly smaller than the diameter of structure they were inserted into so that they would be able to pass through unobstructed.

https://www.vapar.co/lessons-from-parisian-sewers-and-sewer-balls/