Sand Dams An Answer To World's Water Woes? (Video)
Video: In the first of a series of mini-films, Excellent Development explains how its approach to creating development through conservation is benefiting communities in Kenya
The Babylonians used them - as did the Romans and the British during their time in Africa and India. Dating back at least 2000 years, sand dams are an old water-saving method that could be a boon to the world's water-scarce areas. Though it seems counter-intuitive, sand dams are a low-cost, low-tech but effective "grassroots" technique that is already gaining ground around the world - and according to some, could provide millions in arid regions with clean water all year round (no small feat). So how do sand dams work?Water all year round
Sand dams are actually low walls of concrete standing 3 to 16 feet (1 to 5 meters) high, erected across small rivers that stop flowing during the dry season. During the initial two wet seasons, eroded sand collects behind the dam and like a sponge, the sand retains up to 40% of its volume in water while slowing evaporation and filtering water. Locals can then dig wells behind the dam or install pipes under the dam which will supply them with water during the dry season.
"The development challenges in semi-arid Africa are completely different to the industrial nations. In semi-arid Africa it is conservation that can actually create sustainable development," states Simon Maddrell, director and co-founder of Excellent Development, a London-based NGO that focuses on sustainable development in Kenya.
"Water and soil conservation provides farmers with the environment to create livelihoods by creating oases in semi-arid lands that can support water and food security. Arguably, the communities we are working with are doing far more to reverse the impacts of climate change than any of us in the West. They deserve our support, not just because they struggle to sustain their lives, but as global citizens concerned with the future of our planet."
Not only that, implementing sand dams could also help to empower women in these rural communities as well. "Women in Africa do most of the farming," says Maddrell. "Sometimes they have to spend up to 5-6 hours a day just collecting water. Sand dams near to their village would reduce this to an hour a day. They are quite simply a miracle."