Grey water accounts for approximately 50% of water usage in the average South African home. This includes bath and shower water, basins and dish water.

The other 50% usually goes towards watering gardens, washing cars, etc. A swimming pool changes the equation drastically especially if it is a large pool. 

Recycling and re-using all this water would make a huge positive impact on our fragile environment and you'll save hundreds if not thousands or rands every month. 

The traditional and most common way to harvest rain water is to place a storage tank next to your house with the gutter positioned to fill up the tank with rain water running off the roof.

These days, with modern architecture and even the good old fashioned thatch roof, there might not always be a gutter/gutters that one can use to channel rain water into a tank.  In such cases there are a number of alternative methods one can implement to harvest rain water in one's garden.

One option is a rain bed created around the house under the drip line of the roof. This rain bed usually consists of succulent plants and coarse gravel/dump rock with a 300mm deep flower bed of typical garden soil for plants to grow in. Below this upper layer of soil and plants is the lower section consisting of perforated drain pipes making up a network of piping which then channel the harvested rain water into an underground storage tank. One would then pump the harvested rain water directly from the underground storage tank back up to the house or garden.

Another option for gutterless roofs is to collect storm water run-off that streams down your driveway/paving around the house. This too can be collected in an underground storage tank which then also gets pumped to where ever it�s needed by means of a submersible pump. 

Once you've harvested your rain water and stored it in an appropriate storage tank there are various ways to filter and purify water to a usable state.