Domestic Sewage Treatment Plants for Houses Without Land in France

Houses with a limited plot of land have the choice between two types of individual domestic sewage treatment:

• Small wastewater treatment plants: an all-in-one wastewater treatment system that allows for a minimal footprint. At the most, the system occupies only about 10 m² on your land. By comparison, a septic tank with its percolation area has a footprint of between 50 m² and 150 m².
• Compact filters: composed of a septic tank and a filter bed, the compact filter needs a larger surface than the small wastewater treatment plant. It is ideal for secondary homes as it does not require electricity.

Installing a small wastewater treatment plant or a compact filter allows you to solve your problem of lack of space when the available space is too narrow for a traditional sewage treatment plant. Indeed, a small wastewater treatment plant, for example, will always be able to “slip” between your house and the limits of your land.

In the most extreme cases, if the safety distances cannot be respected in relation to rolling loads (vehicle passage) or static loads (building), reinforcements can be placed on the inner walls of the excavation to prevent the tank from being crushed. These reinforcements will be calculated by a specialised design office.

If your house has no land, some small wastewater treatment plant can even be installed above ground (for example in a cellar or a garage – see images below) with reconstituted underground installation conditions (tank filled inside a retaining wall specially built for it).

Small wastewater treatment plants from 1 H to 60 H:

• simple, robust and reliable
• fixed culture system
• light to handle and transport

It is also possible to ask for an authorisation from your town hall (mairie) to install your individual domestic sewage treatment on a communal plot of land, subject to its authorisation or to install it at your neighbour’s place with his agreement, which can sometimes be difficult to obtain.

Finally, if several neighbouring houses are concerned by this problem, a grouping is possible on a single domestic sewage treatment system called “semi-collective.” This solution can be advantageous for all because the grouping of several houses allows to share the costs of the purchase of the system and its installation; on the other hand, the management of this organisation can sometimes generate some difficulties between co-owners.

Is it possible to obtain a building permit for a house without land?

In accordance with the French town planning code, if there is no connection to the sewage system and if it is not possible to install a domestic sewage treatment system on the land of your future house, the building permit will not be granted.

Many domestic sewage treatment solutions exist for houses without land. The installation of a small wastewater treatment plant or compact filter is the preferred solution because of its extremely small footprint and its possibility to be installed above ground.