Claire Benveniste is a sanitation specialist and manages a french blog about sanitation called La Fée Cale. This blog post originally appeared in French here.
Those who build, manage and maintain our toilets and what’s next are not known and recognized despite being essential. Working in sewers is fascinating, but also risky! Here is an example at the heart of Paris sewers.
There was a time when I used to wade with joy through Paris’s sewers several times a year. The advantage of living in a city where many people are packed together is that sewers are big (up to several meters in diameter). Therefore, you can move around pretty easily in most of the pipes with a straight spine (especially if you’re shorter than 1.7 meter/5’7”).
Sewer Exploration – Greater Paris Area © Claire Benveniste
But exploring sewers is risky. You can’t start the adventure overnight.
To become a sewers’ explorer, you first need to go to Pasteur Institute to get vaccinated against leptospirosis, an infectious disease transmitted by rats who are fond of underground mazes.
You then learn about sewer risks, including falls and gasses that are smelly and harmless in low concentrations, but in higher concentrations are odorless and deadly. This particular sewer gas is called hydrogen sulfide, or H2S, and comes from our degraded feces. Unfortunately, H2S can hide within gas pockets that can be fatal if suddenly pierced through.
Risk of a H2S High Concentration © Claire Benveniste
The last step is to get equipped with a full gear: a protective coverall, boots that consume your whole legs, gloves, and a harness with a gas detector and a respirator for emergencies. The icing on the cake is a helmet with a light on top of it. And here you are, ready for underground exploration, donning a historical level of sex appeal.
Before going down, you call those in charge of managing the sewer network to make sure you don’t get swept away by, for example, a sudden wave from a valve. Then you aerate the underground pipe by opening at least 2 manholes. You put your gas detector fixed to a rope down there to ensure dear H2S is not waiting for you in a high concentration.
Once you are clipped to a fall stopper, you slip down through the manhole as smoothly as possible (being slim helps here). You climb the ladders down to the bottom of the pipe, which is sometimes several dozen meters lower. You can then wade through thigh-deep water (sometimes rainwater, sometimes wastewater, sometimes both).
You will learn very quickly to stop the habit of touching your face. ツ
Going Down Paris’s Regional Sewers © Claire Benveniste
Needless to say, you get out of the sewer absolutely wiped out. For an even more concrete immersion, you can watch this TV report from France 3: Diving into Metz’s sewers.
I used to often dive into this underground universe. Sewer workers spend every day in there to monitor, repair, cure, and unplug our sewers systems. It’s one hell of a job!
Their life expectancy is much lower than average because of unsanitary working conditions, which lead to higher instances of digestive, respiratory, skin diseases, cancers, and suicides. On top of that are deadly accidents at work that still occur, despite all the precautionary safety measures - in sewers and wastewater treatment plants.
In 2009, I worked as a technical expert following a sanitation worker’s deadly accident at Achères wastewater treatment plant, near Paris (the biggest in Europe). The worker died after falling down in a pipe leading to an aeration basin. One of the most recent deadly accidents happened last December in Bristol, UK, where the explosion of a wastewater treatment plant killed four.
To know more about what risks sanitation workers are facing in France, and if you can read French, I recommend reading:
an article "One day with" from Work and Safety, a monthly publication from the National Institute of Research and Safety;
an article from Actu-environnement: "Sewer workers threatened by chemical and biological agents cocktail, highlights the National Agency of Food Safety, Environment, and Work";
an article from Bastamag "With the upcoming retirement revision, will sanitation workers be deemed to die at work?"; and,
a report from the National Agency of Food Safety, Environment and Work, mentioned in the articles mentioned above: "Risks factors potentially related to a higher mortality rate of sewer workers".