Recovery of rainwater
Verified 12 December 2025 - Public Service / Directorate of Legal and Administrative Information (Prime Minister)
You want to know if you can retrieve rainwater for your personal use ? Rainwater is unclean to the human consumption, because it is contaminated. Sound usage is therefore strictly sidebar. We're taking stock of the regulations.
This consists in recovering the water from atmospheric precipitation collected downstream from surfaces inaccessible to people, excluding maintenance and maintenance operations. In other words, it is water collected downstream of inaccessible roofs (i.e. where the water goes down).
This water can contain chemical pollutants, such as pesticides, metals or asbestos fibers from roofs.
This water is not safe to drink because it can contain chemical pollutants, such as pesticides, metals or asbestos fibers from roofs. It is therefore considered as water unfit for human consumption (EICH). For this reason, its use for personal purposes is permitted only in certain cases.
It exists 2 main categories of rainwater harvester:
- With connection (it is connected to the indoor network of your home and allows you to use rainwater for certain uses inside your home)
- Without connection (it is not connected to the indoor network and its use is completely separate and limited to uses outside your home).
Rainwater harvester with connection
The rainwater harvester can take the form of a above-ground tank or buried tank (the buried tank generally has a larger storage capacity).
This equipment is available in DIY stores.
It should preferably be settled close to a roof or gutters to facilitate the collection of rainwater.
FYI
Storage of rainwater in tanks can promoting the proliferation of tiger mosquitoes, vectors of diseases (dengue, chikungunya, zika). To avoid this risk and any sanction (commitment of your civil liability, fine), certain municipalities or departments require by decree to cover rainwater collectors and to settle anti-intrusion systems.
Rainwater access valves must be clearly identified and designed to be lockable. Their opening must require a specific tool, which must not remain permanently fixed to the tap.
Each rainwater draw-off point (i.e. where rainwater is drawn) and the toilet supplied with rainwater shall be marked with a plate Non-potable water with an explicit pictogram.
This signaling device is available in DIY stores.
Warning
He is forbidden to connect a rainwater harvester to the public drinking water network. This must be completely separate and distinct from the public drinking water system. In fact, a connection could contaminate the entire public network and endanger the health of users. In addition, it is also prohibited to settle a rainwater tap in a room where drinking water taps are located. Only cellars, basements and other ancillary rooms such as garages are allowed.
Rainwater harvester without connection
The rainwater harvester can take the form of a above-ground tank or buried tank (the buried tank generally has a larger storage capacity).
This equipment is available in DIY stores.
It should preferably be settled close to a roof or gutters to facilitate the collection of rainwater.
FYI
Storage of rainwater in tanks can promoting the proliferation of tiger mosquitoes, vectors of diseases (dengue, chikungunya, zika). To avoid this risk and any sanction (commitment of your civil liability, fine), certain municipalities or departments require by decree to cover rainwater collectors and to settle anti-intrusion systems.
It all depends on the type of rainwater harvester: with or without connection.
Rainwater harvester with connection
Recovered rainwater can only be used for the following purposes:
- Washing of laundry
- Washing of indoor floors
- Removal of feces (urine, feces, ...).
Warning
He is forbidden to consume rainwater. So you shouldn't drink it. You should also not use it for cooking or washing dishes.
It is also forbidden to use rainwater for thebody hygiene.
Rainwater harvester without connection
Recovered rainwater can only be used for the following purposes:
- Feeding of decorative fountains not intended for human consumption
- Cleaning of external surfaces
- Washing vehicles when it is carried out at your home
- Watering the vegetable gardens and green areas of your property.
Warning
He is forbidden to consume rainwater. So you shouldn't drink it. You should also not use it for cooking or washing dishes.
It is also forbidden to use rainwater for thebody hygiene.
YesHowever, some municipalities offer subsidies to buy a rainwater harvester.
In addition, some municipalities provide rainwater collectors free of charge to their inhabitants.
To obtain this information, you must contact your town hall.
No, the equipment can be settled by yourself or by a qualified professional of your choice.
Yes, if your rainwater harvester is plugged in.
The declaration must be made to your town hall, on free paper. Some town halls provide a specific form (often available on their website).
Your declaration must include the following information:
- Address of your accommodation
- Assessment of the volumes of water used inside your home.
Your declaration must be filed or sent to the town hall to the department in charge of sanitation.
Your rainwater harvester must remain in good working order throughout its lifetime.
One visual examination must be carried out annually to check its good condition.
To avoid any risk of contamination, a regular maintenance must be done. This maintenance shall include at least:
- Compliance control of water networks
- Replacing filters
- Maneuvering valves and draw-off points
- Emptying and cleaning of storage equipment.
It is not necessary to use a qualified professional to perform these operations.
Warning
You should not apply anti-freeze in the storage tank, as it can degrade the water quality.
YesHowever, if your water collector is connected, an officer from your town hall's drinking water service can check your facility if there is a risk of contamination of the public drinking water system.
The inspection costs are at your expense.
If the agent detects an anomaly, he will ask you to make improvements to your installation (for example: modify existing connections to eliminate any risk of mixing between rainwater and drinking water, set up clear signage, regularly maintain the recuperator to limit health risks).
If you refuse to carry out these measures, the town hall can proceed to the closure of your water connection, possibly with the recourse of the public force.
In addition, in case of contamination of the public drinking water network, you risk 3 years in prison and €45,000 of a fine.
Definition of rainwater
Use of rainwater
Use of rainwater
Ministry of Health