An Innovative solution to East Africa's Water Crisis

Water has been called the defining crisis of the twenty-first century.  No one knows this better than the water-starved countries of East Africa.  Arid and Semi-Arid land (ASAL) covers almost eighty percent of the East-African country of Kenya (Ominde), and between thirty-five and forty percent of Kenyans reside in these seasonally dry areas (SASOL).  

This presents the Kenyan government, who normally owns the water, a serious problem:  How do we provide enough water to sustain the lives and livelihoods of the millions of Kenyans living in the ASALs?  The answer is two-fold and has been answered by different groups in similar ways.  First, small communities in these areas must provide their own water, and second, this can be done by installing sand dams. 

Because the East-African country of Kenya straddles the equator, it goes through a short and long rainy season broken by a short and long dry season.  The seasonal riverbeds created by these seasons provide water for a few months out of the year, but the water is full of sand and mud from upstream and quickly empties or dries.  

Sand dams make use of the rainy seasons and the sandy water by creating artificial aquifers in the seasonal riverbeds.  The sand washed down the river accumulates over two or three rainy seasons behind the concrete dam and actually retains up to forty percent of its’ volume in water (Brahic).  This shallow aquifer can provide water to a community for many months after the rainy season has ended.

Excellent Development is a London based charity founded by Simon Maddrell and Joshua Mukusia which focuses on the development of Kenyan water sources.  Practical Action is also a UK based charity which focuses on Kenyan water sources with a foundation built on studies done by Sahelian Solutions Foundation (SASOL) and Maji na Ufanisi.  Both organizations use the construction of sand dams to improve the reliability of water to communities in the ASAL areas of Kenya, and consider the project’s life-line the community that the sand dam will benefit.  

SASOL states, “The local community has to take the initiative, indicate the stretch of river where water storage would be most useful, and agree to provide the labor needed” (SASOL 36). Excellent Development corroborates claiming that the success of a sand dam depends, not only on correct design, but also on community ownership (Excellent

Seasonal riverbeds provide the best location for the dam, whose foundation must be based on an impermeable sub-layer of bedrock found by digging a trench across the riverbed (SASOL 37).  The dam itself is then constructed of materials mostly found in the local community; timber, sand and stones, and water with the exception of Portland cement and binding wire (Practical). 

Portland cement can be a very costly material for the communities, costing around Ksh 1000 per 50 kg bag in Nairobi and constituting around 85-90 percent of the total construction of the sand dam. This has led to research into alternative materials for the construction of sand dams in the lands of East Africa.