Using Seawater for your Swimming Pool

The scarcity of fresh water is a growing challenge in many parts of the world, leading to the search for sustainable alternatives to water use. In recent years in Europe, governments in countries such as Portugal, Spain, Italy, France and Malta have implemented measures to restrict the use of water to fill private swimming pools in order to combat shortages during periods of severe drought.

The use of seawater in swimming pools is an innovative solution that can help mitigate these restrictions on the use of fresh water, especially in periods of drought - and brings some additional benefits!

Not only does this practice provide a sustainable alternative to water supplies, but it can also offer therapeutic benefits due to the presence of minerals in the salt water. However, in order to use seawater in your pool, there are specific requirements to take into account. Here are some topics to consider to help you take the plunge.

Advantages of using seawater

• Sustainability: Reduces the use of fresh water, an increasingly scarce resource.
• Less Use of Chemicals: The natural salinity of seawater can reduce the amount of disinfectants needed.
• Health Benefits: Salt water is known for its therapeutic benefits and can help with circulation and skin health.
• Savings: In the long term, it can represent significant savings on chemicals and fresh water.

Water Treatment

Seawater requires disinfection to eliminate pathogenic microorganisms. Salt electrolysis, which converts salt into chlorine, is the most effective and sustainable method for this model of pool, as it reduces the need for additional chemical products and takes advantage of the salt naturally present in seawater. When choosing salt electrolysis for your pool, pay attention to the specifics of the equipment, as not all models are suitable for use with seawater. In swimming pools with seawater, the salt concentration is naturally higher, which may require adjustments to the electrolysis system to ensure the effectiveness of the treatment and the comfort of users.

It's important to choose reliable equipment, suitable for the volume of the pool, for greater durability and self-cleaning systems to prevent limescale build-up. When choosing your electrolyser, check that it is capable of working with salt concentrations of more than 35g/l.

Equipment and materials

Due to the high concentration of salt and other minerals, the use of seawater in a swimming pool makes it necessary to use equipment that is resistant to corrosion caused by salinity. Pumps, filters and pipework must be made of highly resistant materials. To protect accessories such as ladders and handrails, install sacrificial anodes, which are pieces of metal that are more reactive than the pool components and corrode first, thus protecting the other components.

As with any other pool, it is also essential to keep the pH, alkalinity and chlorine stabilizer levels balanced to prevent corrosion.

Salt water must be drained in such a way as not to contaminate fresh water sources and local ecosystems. Adequate drainage systems and effluent treatment are essential. If possible, consult local regulations on the proper disposal of pool water.

To summarize, using seawater in swimming pools is a viable and beneficial alternative, both from an environmental and economic point of view. However, it is essential to ensure that the treatment and drainage systems comply with local rules and regulations to protect both users and the environment.