At a time when water consumption is becoming a global issue, are you wondering how to reduce your pool's consumption? Discover the sources of water consumption in a swimming pool and a few tips that will help you reduce consumption and save money. The right equipment and weekly routines can effectively reduce water consumption.
Evaporation is the main cause of water loss from an outdoor pool. It can account for 10 to 30% of annual consumption. In summer, an uncovered 8 x 4 m pool can lose up to 2.5 m3/week. The average evaporation rate in summer is 3 to 7 mm/day.
Temperature variations have a strong influence on evaporation. The hotter and drier the air, the more intense the phenomenon. For example, an air temperature of 30°C with wind can double water loss compared with a day at 20°C with no wind.
Evaporation is generally higher during the day, particularly when it's hot, dry and windy. However, significant losses can also occur at night if the pool is left uncovered, especially after hot days when the sun is setting.
Using a thermal cover or shutter can reduce evaporation by 40-90%, which represents significant water savings. What's more, it's important to choose a cover to suit your region: the wetter (acidity) or windier (pollens) the region, the greater the need to protect your pool to preserve water quality.
Another significant source of water consumption in a swimming pool is maintenance of the filtration system, in particular backwashing of the sand filter. In addition, other operations such as pool cleaning, manual washing of cartridge filters, and partial or complete emptying are also carried out.
Over a season, it is estimated that these filter washing operations can lead to an annual consumption of 5 to 10 m³ of water for a standard family pool.
This operation, which is essential for maintaining good filtration quality, involves reversing the flow of water to remove impurities trapped in the filter. It should be carried out regularly, generally every 1 to 2 weeks when the pool is in use, depending on how often the pool is used and the environment. This can represent between 15 and 25 operations per year.
Each backwash can consume between 0.2 and 0.5 m³, and often needs to be followed by an additional rinse of the filter.
Using a properly sized and maintained filter reduces the frequency of backwashing.
If possible, depending on your region, you can actively winterise without lowering the water level.
If you live in a region where frost is frequent in winter, the water renewal rate will vary from 10 to 30% maximum.
In theory, a swimming pool only needs to be filled once, and the water can be stored for many years.
A swimming pool should only be drained completely or almost completely if there is an urgent need to do so. In fact, a swimming pool can only be completely drained if work is being carried out on it, if the pool walls are too full of scale, or if the water is saturated with chlorine stabiliser or has deteriorated too much. That's why you need a few minutes' special care every week
Total emptying then represents a loss equivalent to the total volume of the basin (often between 40 and 70 m³).
The last reason for losing large volumes of water is the most obvious: a leak.
A small leak of 1 mm in a fitting or pipe can lead to a loss of 1 to 2 m³ of water per day. Over a full season, this can represent several tens of cubic meters, even exceeding evaporation losses if the leak isn't detected in time.
There are certain warning signs: an abnormal need to add water, a constantly damp area of ground around the pool, or an unexplained drop in water level even when the pool is covered.
In this case, the intervention of a professional equipped with detection equipment (thermal cameras, pressure test) is recommended to precisely locate the leak: structure and lining of your pool, pipes and filtration system.
Estimates of water consumption for a swimming pool may vary according to sources, calculation methodology, local climatic conditions and user behavior.
On average, a swimming pool consumes 15m3 of water per year. In 25 years, water consumption has almost halved (-45%).
| Minimum estimated annual volume (m3) | Estimated maximum annual volume (m3) | |
| Upgrade: evaporation | 10 | 20 |
| Maintenance (filter backwash, cleaning) | 5 | 14 |
| Refresher course: splashes | 1 | 3 |
The FPP has set up a pool water consumption calculator To estimate consumption, the calculator takes into account around fifteen parameters (location: rainfall and sunshine, surface area and volume of the pool, equipment and usage habits). A coloured indicator shows the level of consumption. This helps to identify the best levers to use to reduce water consumption.
Over the past twenty years, pool professionals have made significant innovations in the choice of construction materials, the efficiency of filtration pumps and protection systems, which are now much more effective than in the past and help preserve water quality. These investments will enable you to save water and often also consume less electricity.
Filtration accounts for 80% of water treatment and plays an active role in maintaining water quality by reducing the need for water renewal.
Il existe plusieurs systèmes de filtration (filtre à sable ou verre, filtre à cartouche ou à diatomées) éprouvés qui permettent de maintenir une qualité d’eau constante.
Adapt filtration time in season according to water temperature. Filtration time is easy to calculate: divide water temperature by 2.
The duration and efficiency of filtration are therefore very important if you want to reduce your pool's water consumption.
Bubble covers, bar covers, automatic shutters and shelters limit evaporation and therefore water consumption.
En installant une cuve de récupération de l’eau de pluie (enterrée ou anti-UV), vous pouvez vous servir de cette eau pour mettre à niveau l’eau dans votre piscine.
The Federation of Pool and Spa Professionals recommends a weekly 30-minute routine to clean the pool, then analyze and treat the water.
Check the water line level: 2/3 of the way down the skimmer
Keeping the water of good quality at all times limits the need for renewal and partial emptying. At the start of the season, it's vital to check the water quality, in particular the water balance (pH, TAC, TH). Then, throughout the season, it is advisable to monitor and maintain the pH and disinfection quality.
In addition, connected water analysers such as ICO are used both to monitor the water in your pool every hour and to guide you with recommendations for treating the water effectively at the right time, before its quality deteriorates. In this way, you can effectively maintain the quality of your water, without having to renew it.
La consommation d’eau d’une piscine dépend fortement de l’évaporation, de son entretien, et d’éventuelles fuites. Le choix des équipements et l’adoption de bonnes pratiques peuvent réduire considérablement la consommation
