1. Historical background

Even in the first part of the 20th century, in rural areas, the use of more or less well-designed latrines was common, if not open defecation in a discreet corner of the house was the rule.

As cities developed and modernized, the situation changed. In addition, the hygienist doctrine advocated routing dirty water out of the city, leaving it to flow by gravity. This is how the first sewers were built, collecting water from all sources: houses, roads, human activities...

The collection and treatment of wastewater only became widespread after the Second World War, with the Water Agencies playing a major role in this development from the 1970s onwards.

However, the "all-pipe" approach has reached its limits in some areas. On the one hand, the cost of connecting isolated houses and buildings can be prohibitive. Secondly,...