Water-recovering systems and types of pool border

There are two main systems of water-recovering from pools:

• Inside water-recovering system through outlet located into the pool.
• Overflow water-recovering system through the overflow of water.

The main advantage of overflow water-recovering systems is to keep a constant water level into the pool and these are divided in:

• Punctual water-recover systems, generally used for private pools, where water is recovered through few particular water outlets called “skimmers”.
• Continuous water-recover systems, more used specially for larger pools, where water is recovered by overflow, through an adjacent scum channel, along one or more pool sides.

The overflow systems with continuous water-recovering have the advantage to remove the upper water film thus collecting all floating dirt and leaving clean water into the pool.

Usually, the regulations for water treatment state that at least 50% of water into the pool is recovered through overflow systems and the other 50% through inside systems.
The ideal solution would be to recover the total quantity of water through overflow systems.

The overflow systems with continuous water-recovering are then divided into:

• External scum channel systems, where water is recovered through an adjacent scum channel positioned on the pool deck.
• Internal scum channel systems, where scum channel is positioned on the walls inside of the pool.

Over the time, the following main pool border types have been developed; the Finnish system, the Wiesbaden low-level system, the Wiesbaden high-level system, the St. Moritz system and the Zurich system besides pool borders for private pools.