Canals and Streams in Garden water Features

Water was one of the earliest features to be introduced to the garden. It is considered particularly precious in countries with hot, sunny climates, but it is just as appropriate in more temperate conditions under much greyer skies.

Water adds sound and texture to a garden and, as ornamental details, water features will attract attention, drawing the eye towards them. Water can be spread in a vast sheet or it can be kept to a smaller area, such as a pool or rill, partially hidden by vegetation. Running water, either splashing in a stream or playing in a fountain, introduces a pleasing sound and creates a lively atmosphere. It brings movement and moving images that sparkle with every ripple and splash. Conversely, the mirror-like surface of still water has a superb reflective quality which adds further scope to a design. Another benefit of water in the garden is that wildlife will be more plentiful.

It takes a certain amount of planning and effort to introduce a water feature in a garden, and such a project should not be undertaken lightly or without a firm commitment to success; a wrinkled black or greying plastic liner, half-filled with dirty water, does little towards producing an attractive garden. If in any doubt about your construction abilities, employ a water garden specialist to do the job for you.

Canals and Streams

A garden with naturally-running water is a rare blessing; most people have to be content with constructing artificial streams using pumps to recycle the water. However, impressive and realistic results can still be achieved by artificial means.

The design of a canal or stream very much depends on the garden and whether there are any natural slopes down which water can flow. Running water does not require a steep gradient, and if no slopes exist it is quite easy to construct one with a sufficient incline to keep the water moving. Informal streams can be incorporated into rock gardens or natural, wooded banks; install a pool or create a spring at the top of the slope and construct another pool at the bottom of the stream, from where the water is recirculated by means of a submersible pump.

Streams that are irregular in width, depth and direction can be made with a strip of butyl liner, much in the same way as the construction of pools or, if the watercourse is very irregular and includes waterfalls, it may be easier to use several pieces of liner instead of one large strip. The joints should have a good overlap of liner, a minimum of 6in (15cm) depending on the steepness of the slope, the uppermost piece pointing in the same direction as the flow of the stream.

It is also possible to construct streams using concrete and waterproof cement. The ground beneath the feature should be well compacted, with a layer of hardcore for extra support to ensure that the finished, set concrete does not crack.

When using either a liner or concrete, be certain that the bed of the stream is flat so that the flow of water will cover and disguise it completely. If using concrete, you can implant rocks in the semi-wet concrete along the margins to give a more natural appearance. With a liner, any rocks must be placed on the bank overhanging the channel so that they do not come into contact with the liner and risk puncturing the material in any way.

For a more formal feature, a straight-edged canal built of concrete and cement can be built between regularly shaped pools.