Sand Dams are a low wall built, using basic materials, across seasonal river beds where water has channelled through rocky substrata, a familiar dryland scenario where water briefly flows and hitherto has been lost. The rainy season brings a flash-flood of water that includes vast quantities of sand in suspension which settles behind the new Sand Dam wall.
Above picture by courtesy of Polly Braden
Once the deposited sand reaches the top of the dam wall the resulting “reservoir” can stretch several kilometres upstream, safely and sustainably trapping millions of litres of water in a sand “sponge” that is refilled every time it rains. Crucially, during the dry season the water is thus protected from evaporation and runoff so that year-round fresh water is available to the local communities for evermore by the simple expedient of digging a shallow well.
Excellent are the starting point. Following community consultation they provide the skills and training for the proposed Sand Dam as well as resource that is not available locally. The communities then input locally-sourced materials and labour to create what is, in effect, a professionally guided, self-help, sustainable investment in that most basic of commodities: water.
There are no hand-outs with this intensely practical solution, just long term benefit. The resulting Sand Dam, once “filled”, supports livestock and basic cropping as well as providing potable water. Following dam completion further input to the communities, including advice and help with sustainable agriculture, creation of seed banks, terracing technology and other appropriate methodology, is then made available through Excellent’s partner, ASDF – the Africa Sand Dam Foundation.
Read more about Excellent and their vital input to dryland sustainability here:
What is a Sand Dam?: www.excellentdevelopment.com/what-we-do/pioneering-sand-dams
Film about Sand Dams: www.youtube.com/watch?v=HsUYYfwleyU
How Sand Dams work: www.excellentdevelopment.com/what-we-do/pioneering-sand-dams
Where Excellent operate: www.excellentdevelopment.com/where-we-work
Excellent Films: www.excellentdevelopment.com/films