Sand Dams

Sand dams can provide ample water in dry drainage regions especially mountainous ones.
Ideally, steel reinforced concrete is deployed to construct a water tight barrier dam, however, reasonable results might be achieved with dry stone walls and “clay berm” provided “down stream” support in the form of “back fill” is added as an additional brace against water pressure. Clay is somewhat impervious to water flow. A clay berm alone would work and possibly a simple plastic sheet could be arranged to hold water.

In the case of a back filled dam both the wall and water presence would be invisible at the surface and thus might represent a hazard to traffic. Certainly heavy traffic would have a difficult time with a %40 – 60 water plus sand mix ( quick sand ) and might need to be clearly marked as a hazard.

Sand Dam Links:

New Scientist
Practical Action ( .pdf )
Water Aid