Most of us want our water features to look 'natural', but ponds often need to go against walls, or next to (or indeed on) patios: hardly 'natural' settings. But a garden stream can look really natural. Even though it is merely a stretch of water going from one place to another, this is exactly the sort of phenomenon that is found in the wild.

In all cases, of course, a man-made stream will contain water that is circulated by a pump. Pumps obviously vary hugely in their performance, and it is crucial that you choose one that will provide the desired effect. For example, a small pump in a very wide or deep stream would produce an imperceptible and completely ineffective flow.

The stream should be made dead level, so that it remains full once the pump is switched off. And, when the pump is off, your 'stream' will become a shallow, elongated pond. One of the trickiest decisions when creating a stream is how to make it suddenly 'appear' in the garden, and then 'disappear' further along. A gurgling stream usually ends up emanating from large pipes or from beneath a stone slab; it will almost certainly disappear in the same way. Most of the gullies the water will travel along are made from concrete, stone or brick, and are either straight or gently curving. Flexible liner can be used, but use gravel, sand, stones, bricks or boulders to give the water a rippling texture and help conceal the shiny PVC or plastic.

If an abrupt change of direction is required some way along the stream, it is best to cover the stream at that point with some sort of chamber, so that water can enter it from one direction and leave in another. Such a chamber could also be used to hide the beginning or end of the stream.