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Construction, operations and maintenance
* In upstream parts of a catchment it is recommended that sand dams are always built in stages, since the availability of coarse material is generally limited and base flow is small or absent (base flow = sub-surface flow which aids surface flow so that silt/clay can still be flushed away once rainfall stops, rather than sinking directly into the sand bed). It has also been suggested that to build in stages over several years is also more beneficial for functioning of dam committees. Build them within a spillway, which was part of the first stage & wing wall construction.
After the dam is built, an outlet for water extraction must be constructed. Hand dug scoop holes are the simplest possibility, however the water can easily be contaminated. Covered wells, with hand or rope pumps protect the water much better. It is also possible to construct an outlet pipe with a tap. This however is difficult to maintain, and can weaken the dam. Meanwhile the local community needs to be trained to manage and maintain the dam.
====Operation====
[[Image:Sand dam scoop hole.JPG|thumb|right|150px|Women fetching water from a local aquifer through scoop hole]]
[[Image:Sand dam well.JPG|thumb|right|150px|Closed well near a sand dam]]
First an appropriate site needs to be selected, depending on whether it is suitable for a sand dam or not. Then the best section of the riverbed is chosen. Then the dam is designed, depending on the conditions and the water needs of the community, and built. It takes a few rainy seasons to let the aquifer fill up. After that an extraction point is constructed such as a scoop hole or well. Then water can be extracted and used for drinking, agriculture, etc. Meanwhile the local community needs to be trained to manage and maintain the dam.
====Maintenance====
====Estimated Lifespan====
The lifespan depends on the materials used and expertise with which it is constructed and maintained. The dams in Kitui Kenya were built at a cost of 7500 USD and have a minimum lifespan of 50 years.
==Costs==
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