Planning Size, Shape & Materials for Your Water Feature

Do it right first time by planning your water feature project in some detail ...

Plan every single sod of earth you dig and cost every trowel of cement you mix. Go through the job from start to finish in your mind working out quantities and costs of materials.

Having chosen the site, choose the shape that most befits it. Ponds closer to the house tend to be more formal, further away they can be more natural looking. However they can mark the boundary between formal hard landscaping and a more informal area, for instance when a pond adjoins a patio or decking.

Lay a rope or hose on the ground to get the best idea.

Try to draw a plan of it in relation to the rest of the garden. Ideally do a sketch as to how you would see it from the position you are most often going to view it from. Or take a photograph of the site and draw the pond in position on some tracing paper laid over it.

Size and Shape

Make the pond as large as your pocket or your energy will allow. The larger they are, the steadier is the balance they maintain. The absolute minimum is 32 sq ft or 3 sq metres.

Unless you plan to keep Koi carp, a depth of more than 30ins (76cm) is unnecessary. 18-24 inches (45-60cms) is adequate.

If you are using a flexible liner, keep the shape as simple as possible, as dramatic shapes use excess liner and create unsightly folds. Water circulates through the pond much more easily too.

Planning a Stream?

Beware of making the stream disproportionately large in relation to the pond. Remember, the stream needs an addition of at least an inch (12mm) of water added to its surface to get it flowing. On top of this there is a backlog of water hidden within the system and combined together this can mean a considerable loss of water from the pond once the stream is full flood. The marginal plants in particular cannot cope with the radical rise and fall of the water (see also Estimating and Avoiding Problems Streams and Waterfalls).

Materials for Your Water Feature

Get your materials (yes use branded liners, top notch branded low power consumption modern pumps, etc) from a reliable retailer close to hand. Look into what is available and you will find the competitiveness of the industry has created a range of materials whose price is related to performance and durability i.e. you get what you pay for. It would be recommended for the larger projects in particular to opt for the better quality materials, even if it means having to cut back on the size of the pond.

This site only covers the techniques of pond and water feature construction using flexible waterproof liners and preformed plastic and fibreglass ponds. Using clay and doing genuine puddling is beyond the resources of most amateurs and concrete ponds require a certain amount of builders skills mixed with time, patience and a great depth of pocket!

To further help with the choice of materials, there is a list of facts and tips related to individual items or features on pages in the section ... Estimating and avoiding problems.

Pond Filters, Lights and Lighting and Water Feature Electrics

If you are including a biological filtration unit or lights, make allowances for them at the initial planning stage. Both will need an electrical supply. A biological filter will need a submersible pump that will capable of pumping half the volume of the pond through the filter every hour. The filter will also be designed to cope with the capacity. Some people have the filtration unit dispensing the outlet of water into the head of the stream or waterfall. Considering the filter has to be going 24/7 to be effective and you dont necessarily want a stream running constantly, I always feel it best to have it a separate entity. Check with your local aquatic stores for the latest filtration technology; there are new products being constantly developed.

Also the development and standards for safe electrical installation out of doors are always being updated. The essential thing is that there must be a highly sensitive circuit breaker (RCCB, RCD) of the correct standard (at the moment 30ma) between any exterior electrical items and the domestic power supply. If you have any doubts about your safety, consult an electrician. At least get one to check your installation.

All connections to the power supply outdoors must be made with the most modern connectors fitted with the utmost care.