You’re a very hands on home owner, good with tools, have access to JCBs, and you have friends in construction….maybe the self-build natural swimming pool is an ideal solution to the costs of hiring a commercial firm to design and build your bespoke natural swimming pool. A dream family sized pool designed and installed by a professional firm is likely to set you back anywhere between £40,000 and £120,000.

There have been many fairly successful examples of self build natural swimming pools on the continent, where the idea has been popular for a lot longer than in the UK. The website http://www.schwimmteich-selbstbau.de/index.html shows off many keen selfbuilders in Germany, and various forums available have allowed the public to compare notes.

There have also been various self build packs available commercially that have made the process a little easier, and now Michael’s new book also gives a lot more power to the self builder to pick up robust construction methods. Self build kits will no doubt continue to improve. The use of Ultra-Violet sterilizers or clarifiers within the pool circulation system allow the self builder some degree of protection from green water (phytoplanktonic algae blooms), should the finished pond not be the perfect example, or if water chemistry is unknown or beyond the owners capability.

The self builder faces many problems. Many established companies across Europe and the UK will not agree to designing bespoke pools for self builders to execute, or agree to get involved in the construction half way through. These are for reasons of liability as well as the technical know-how and specialist components that go into making the pool work well. One of the main problems in the UK is the terrible levels of phosphates in our water supply in many localities, especially where the mains supply is soft water. Removing phosphates is tricky and were you to get started with a pool filled with such water you will be destined for big problems from the start.

Regardless of the rest of the pools design features, it can be a complex operation building the natural pool’s regeneration zone so it effectively maintains clean and clear water. One way around it of course is to draw water from a borehole and or divert from a stream and have the pool on ‘flow-through’. This does limit your control over water quality and temperature within the pool but hugely simplifies design. I have swum in such a pool in Hampshire, it had simply been lined with clay and straw, with planted margins, and although the base was packed with sediment it was an amazing experience, and one of my first experiences of a natural swimming pool.

The use of large areas of submerged plants, combined with well planted margins (at least 50:50 ratio of swimming area to planted areas) is useful for pools with little technology and filter design. Where depending heavily on plants, the use of circulatory pumps should be minimised and sediment should be guided towards areas where it will not be disturbed or will be easy to remove using a cleaning/sump pump. This type of pool design is great for holiday homes where there will not be anyone around to monitor the pool for long periods, and you do not wish to consume electricity using pumps.