Sand dams
Practical Action
Disadvantage
The technology is labour and physical capital intensive and most local communities cannot
implement it without external aid.
Development of the Technology
Despite its cultural acceptability, this water harvesting technique has not been widely
replicated in other deserving areas probably due to high costs of materials and labour involved
and limited technical skills.
Conclusion
Water scarcity is perceived as the major bottleneck to development in the ASALS and
innovative ways of rainwater harvesting are worthwhile. Sand dam technology that artificially
enhances traditional water harvesting knowledge if well sited can bank of up to 6000m3 of
clean water for domestic use thereby alleviating water shortages during drought periods.
However, the geological characteristics run off patterns of the catchment and sediment
transport regime of the river is prerequisite. Simulated river flow series can be used to
estimate the size of flows likely to occur over a given period. Unfortunately hydrological data
for most seasonal rivers are unavailable thereby rendering many predictions inadequate. For
future development of sand dam technology, there is need to monitor rainfall patterns and
install river-gauging structures along the streams.
Reference
Thomas, D.B (1999) Where there is no water. A story of community water development and
sand dams in Kitui District Kenya. SASOL and Ufanisi, Nairobi.
Joel K. Kibiiy (etal) (2003) Sand Dams: Source of water in Arid and Semi Arid Lands of Kenya
(paper). Proceedings of the International Civil Engineering Conference on Sustainable
Development in the 21st Century, Nairobi, Kenya, 12 – 16 August 2003.
Further Reading
Runoff Rainwater Harvesting Practical Action Technical Brief
The Sri Lankan ‘Pumpkin’ Tank ~ Case Study Practical Action Technical Brief
The Underground Brick Dome Water Tank ~ Case Study Practical Action Technical Brief
Cement Mortar Jar ~ Case Study Practical Action Technical Brief
Rainwater Catchment Systems for Domestic Supply, by John Gould and Erik Nissen-
Petersen, Practical Action Publishing 1999.
Ferrocement Water tanks and their Construction, S. B. Watt. Practical Action Publishing
1978
Rainwater Harvesting: The Collection of Rainfall and Runoff in Rural Areas, Arnold Pacey
and Adrian Cullis Practical Action Publishing 1986
Water Harvesting – A Guide for Planners and Project Managers, Lee, Michael D. and
Visscher, Jan Teun, IRC International Water and Sanitation Centre, 1992
Water Harvesting in five African Countries, Lee, Michael D. and Visscher, Jan Teun, IRC /
UNICEF, 1990. As snapshot of the status of RWH in five African countries.
Waterlines Journal Vol. 18, No 3, January 2000 and Vol. 14, No.2, October 1995 Both
issues are dedicated to rainwater harvesting, available through Practical Action Publishing
Photo-manuals by Eric Nissen-Petersen. A range of manuals on how to build a number of
tank types including: cylindrical water tanks with dome, an underground tank, smaller
water tanks and jars, installation gutters and splash-guards, available from the author at:
P.O. Box 38, Kibwezi, Kenya.
Rainwater Catchment Systems – Reflections and Prospects, John Gould, Waterlines Vol.18
No. 3, January 2000.
Domestic Water Supply Using Rainwater Harvesting, by T.H.Thomas, Director of the
Development Technology Unit (DTU), University of Warwick. The article is available on
DTU’s Website
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