filtration system

Swimming Pool



Swimming Pool Design Engineers

Swimming Pool Design Tips
We have developed a detailed knowledge of all aspects of swimming and leisure pool design. On this page we share with you some of our basic design considerations when developing the specification for a swimming pool.

Pool Water Circulating Systems
Freeboard type. In this type of swimming pool, the top water level is below the surrounding deck. Water normally enters the pool through a selected number of wall inlets, and exits via outlet grids built into the deep end of the pool floor.

Efficient top water removal is essential in this design, as the majority of contaminants lie within the top 25mm. This is usually overcome by the use of a number of surface skimmer units spaced around the internal face of the pool tank. We have calculated to remove at least 25% of the total hourly flow.

Level deck type. In this type of swimming pool design, the build up of contaminants is entirely eliminated as the water passes over the pool perimiter, falling into a channel covered by perforated grating. The water is then returned to the filter plant, usually via a balance tank.

Water Circulation System Design Is Critical
In any type of swimming pool, the correct design of the water circulating system is of paramount importance. Its role is to ensure that filtered, sterile water is distributed evenly throughout the entire swimming pool volume, eliminating any "dead" areas.

Failure will result in areas having little or no residual chlorine content, which then creates the strong possibility of increasing ammonia levels with the consequent growth of green algae.

Pool Water Filtration Speeds
Filter speeds are expressed as the volume of water, in cubic metres, passing through one square meter of filter area per hour (m3/m2/hour).

A low filter rating will maintain a high water quality for longer periods before backwashing is required. Whilst small filters operating at a higher rating are initially cheaper to purchase, they will require washing at more frequent intervals than a filter of a lower rating.

As the water to wash the filters is taken from the actual swimming pool, this water loss has to be made up from the town's water supply - which must be heated and chemically treated, with the consequent recurring costs involved.

We have developed the extremely reliable ‘Auto Top Up’ system which is used to maintain the required water levels in the swimming pool at all times, re-instating the water levels following filter backwash. The first Auto Top Up system was installed over twenty years ago and continues to function effectively and fault free.

Even with the most effective auto or semi auto system, we strongly recommend that the system is manually verified on a planned basis.


Swimming & Therapy Pool Design, Water Treatment & Maintenance