While we live in a country usually known for its abundant rainfall, recent droughts have shown us that everything can change very quickly. Rainwater then becomes a precious resource as it can be used to water the garden, wash the car, and for other daily uses. But how can it be collected and stored efficiently? We compared three solutions: the rainwater collection tank, the plastic barrel, and the underground cistern.
The rainwater collection tank
The rainwater collection tank is a device placed near a downspout that allows collecting water flowing from the roof. It is usually equipped with a tap to facilitate the use of stored water. This rainwater harvesting solution offers several advantages:
- It allows storing a large amount of rainwater (from 300 liters to over 1000 liters).
- It is inexpensive (less than €250) and very easy to install.
- It is durable if you choose quality tanks.
However, keep in mind that it requires regular maintenance to prevent bacterial growth and you must be especially careful in winter due to freezing.
The plastic barrel
The plastic barrel is a cylindrical container with a blue or white lid. It can also be placed next to a downspout, although this is not mandatory to collect a good amount of rainwater. It has similar advantages to the tank we presented earlier. That is, it is very easy to install (no need to carry out work) and its price is affordable (less than 100 euros). Moreover, it is available in various sizes ranging from 60 liters to over 220 liters.
The plastic barrel can thus be useful as a complement to a tank for a specific use (watering your plants, for example). However, it does not allow storing a sufficient quantity of rainwater to be worry-free during a drought. Nevertheless, to save some water, it can be a good solution.
The underground cistern
The underground cistern is the most efficient solution for collecting rainwater and is usually reserved for professionals or people with significant needs. It is an underground reservoir that can store several thousand liters of water. It is connected to a pump that distributes water to different locations. Its primary advantage is protecting the water from freezing and light since it is underground. It is also the most suitable solution to be worry-free during prolonged droughts.
That said, the underground cistern is quite expensive to purchase and complicated to install. In some cases, it is necessary to have a building permit since it may involve significant work. Needless to say, you must be able to justify these costs and procedures, which is clearly not within everyone’s reach!
Comparison of rainwater storage methods
Each storage solution meets different needs: budget, available space, desired volume. This table will help you better compare the options:
| Storage type | Advantages | Disadvantages | Ideal for… |
|---|---|---|---|
| Above-ground tank | Affordable price, quick installation | Sensitive to frost, limited capacity | Gardens, occasional outdoor use |
| Underground cistern | Large capacity, discreet, usable year-round | High cost, necessary work | Families, daily domestic use |
| Wall-mounted collector | Aesthetic, space-saving | Reduced volume, limited use | Small spaces, light watering |
No, rainwater is not potable without specific treatment. However, it can be used for watering, cleaning, sanitation, and even some domestic uses once filtered.
It all depends on your needs and the size of your roof. A small tank of 200 to 500 L is sufficient for a garden, while a cistern of 3,000 to 10,000 L is preferable for full domestic use.
Yes. It is recommended to regularly clean the filters, check the good condition of the gutters, and maintain the tank once or twice a year to ensure the quality of the stored water.
