Sand storage dams are both water sources and storage installations. They typically consist of a partially below ground masonry dam in a sandy and seasonal riverbed. The installations trap sand from seasonal rivers behind dam: a sand body is created hence a new aquifer, to increase groundwater availability. Water retention and recharge also enhances re-vegetation.
Average cost per dam: Kenya – for 2,000 m3 about USD 7,500. Large-scale costs: USD 8,000 – 12,000. OM costs: little to none. Costs include: materials, training, transportation, labor, and construction equipment. Additional costs: 2-4 dug wells with handpumps USD 2,000 – 3,000.
Applicability: community and municipal. Implementation: expert on siting and design, success of dam depends on right location and dimensions, requires experience. Management: lead artesian and community committee for planning, training, O&M. Policies: micro-financing or regional schemes initiated by regional authorities.
Recharge ease: medium, depends on rains, floods, extraction. Ecological footprint: low, if extractions managed and multiple dams on same river spaced apart. Climate change: good, sand dam contains floods, provides water in drought periods. Evaporation is nil, storage in sand.
Lifespan: minimal 50 years with correct siting, construction and maintenance. Level of simplicity: low-tech but site selection and dimensioning is key. Required before first use: expert knowledge with community support, possibly water treatment after extraction. Proper design and siting required.
Community needs to know benefits to be motivated to contribute to labor, management and O&M. As livestock and agricultural benefits increase, community is willing to pay back into system. Reduced water-borne disease, better food preparation, diet and hygiene expected.
No relevant remarks for Sand storage dams.