Ecology

The 5 pitfalls to avoid with a rainwater collector for an eco-friendly and legal approach

On June 17, 2025 , updated on June 17, 2025 - 5 minutes to read
The 5 pitfalls to avoid with a rainwater collector for an eco-friendly and legal approach

The necessity of adopting eco-friendly practices is becoming imperative in a changing world. Installing a rainwater collector presents a major challenge: avoiding fatal mistakes. The main issue lies in the protection of the environment, while complying with current legislation. The question arises: how can we maximize this approach while adhering to the law? The pitfalls are numerous, ranging from an inappropriate installation to irresponsible water management. Avoiding these pitfalls ensures optimized and respectful use of natural resources.

Overview
Error #1: Inappropriate Location – Installing the collector near a gutter on stable ground is essential.
Error #2: Random Volume Choice – Assess the needs in liters according to the size of the garden and the intended uses.
Error #3: Neglecting Maintenance – Regular cleaning is crucial to avoid algae and mosquitoes.
Error #4: Using Untreated Water – Not connecting the washing machine or pool without water treatment is essential.
Error #5: Ignoring Administrative Processes – Informing the town hall and complying with regulations is mandatory to avoid penalties.
Bonus: No Antifreeze – The addition of antifreeze is prohibited; the tank must be emptied before winter.

Install Your Collector in a Strategic Location

A judicious installation requires choosing an appropriate location. Ideally, place the tank at the foot of a gutter to maximize water collection. A stable ground, such as a concrete slab, is a fundamental requirement. A full 500-liter collector can weigh more than 500 kg. Such weight on unstable ground risks causing disasters and significant damage in the garden.

Do Not Neglect the Tank’s Capacity

The choice of tank volume is of great importance. Selecting a size at random, influenced by a promotion, is risky. Assessing usage needs is crucial: for watering, count approximately 15 liters per square meter, and for domestic use, such as toilets, plan for 100 liters per person. Buying a tank that is too large can lead to water stagnation, creating an environment conducive to mosquitoes and algae proliferation.

Take Care of Regular Maintenance

Regular maintenance is imperative to ensure water quality. The gutter requires cleaning at least once a quarter to prevent tank contamination. Emptying and rinsing the tank before winter is essential to avoid algae formation. Other components, such as filters and collectors, should be checked and cleaned several times a year. A mesh also serves as an effective barrier against debris.

Use Water Wisely

Two uses require particular vigilance. Using untreated water for laundry or the pool can lead to serious health risks. Following the guidelines from Anses is paramount, especially for pools, which must be equipped with a UV sterilizer or chlorine. Using this water in the kitchen or for consumption is to be avoided. Safe alternatives should be prioritized.

Complete Administrative Formalities

Legislation imposes obligations to be met when installing a collector. Notably, it is necessary to declare the tank to the town hall if it is connected to the sewage system. Details regarding volume and address are essential, as well as acceptance of technical inspections. Neglecting this aspect can lead to financial penalties or disconnection of the system.

FAQ on the Pitfalls to Avoid with a Rainwater Collector

What are the main pitfalls to avoid when installing a rainwater collector?
The main pitfalls include: installing the collector anywhere in the garden, choosing an inappropriate tank volume, forgetting maintenance, using untreated water for laundry or the pool, and neglecting administrative processes.

Why is it important to place the collector near a gutter?
A good location allows for effective rainwater harvesting, and a full tank can be very heavy, requiring a stable base to avoid accidents.

How do I determine the tank volume I need?
Assess your watering needs: count approximately 15 L per m² of garden and 100 L per person if you plan to use the water for toilets or laundry. Add these needs to choose the appropriate size.

What problems are associated with an unmaintained collector?
An unmaintained collector can become a habitat for algae and mosquitoes, compromising water quality and posing hygiene problems.

Is it true that I cannot use rainwater for my pool or laundry?
Indeed, untreated rainwater presents health risks. For the pool, treatment such as chlorine or a UV sterilizer is necessary, and it is better to use potable water for laundry.

Do I need to complete administrative processes before installing my collector?
Yes, in some cases, it is mandatory to inform the town hall when installing a collector, especially if it is connected to the sewage system. Inspections may be carried out.

What common mistakes are often made when maintaining a water collector?
Forgetting to clean the gutter, rinsing the tank before winter, and checking the filters several times a year are frequent oversights that can compromise water quality.

Why is the use of antifreeze in the water collector prohibited?
The addition of antifreeze is prohibited because it is toxic to the environment. The best solution is to empty the collector before freezing and clean it thoroughly.