Water Harvesting – Guidelines to Good Practice (Water Harvesting)

A sand dam is typically 1 - 5 metres high and 10-50 metres across. When it rains the dam captures soil laden water behind it – the sand in the water sinks to the bottom, whilst the  silt remains suspended in the water. Eventually the dams fill with sand - sometimes after only one rainfall or over 1 – 3 seasons. 25 to 40% of the volume of the sand held is water. A mature sand dam can store millions of litres of water – refilling after each rainfall providing a year round supply to over 1,000 people.
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