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[[Image:traditional hand dug well.png|right]]
[[Image:StoneLiningHandDugWell.jpg|thumb|right|300px200px| Placing a stone lining in a hand dug well. Chiapas, Mexico. Photo: [http://www.flickr.com/photos/aamv/366661815/ The Maya Village Project.]]]
These are shallow wells which draw water from a natural aquifer or man-made aquifer, e.g. near [[sand dam]]s or around [[ponds]], but which are not located inside a riverbed. It can include wells that are far from a river, or wells that receive water from shallow aquifers hydraulically connected to the river. Sometimes the holes dug are very large, allowing people and sometimes animals who are able to walk into the well to where the water is located. <br>
Water extraction can be done with [[Handpumps]] or [[Small and efficient motor pumps]]. A bucket and rope can be used but risk of contamination increases. In such a case, household water treatment should be advocated.
===Suitable conditions===
* Layers of sand and gravel tend to provide good locations for wells and boreholes. Other good locations are in weathered rock in granite areas, along the edges of valleys in mountainous areas or in a river valley where there may be sandy deposits under the banks.
* Care should be taken to avoid siting wells in perched aquifers (shallow aquifers with limited recharge capacity and water storage).
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! width="50%" style="background:#efefef;" | Advantages
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| valign="top" | - Manual access, that can be deepened or maintained easily at a later date
===Resilience to changes in the environment===
====Drought====
'''Effects of drought''': Can dry up perched aquifers; Groundwater levels dropping in perched aquifers.
More information on managing drought: [[Resilient WASH systems in drought-prone areas]].
===Construction, operations and maintenance===
'''General advice on cement''': A common cause of cracks in structures and linings (e.g. in tanks, dams, waterways, wells) is errors in mixing and applying the cement. First of all, it is important that only pure ingredients are used: clean water, clean sand, clean rocks. The materials have to be mixed very thoroughly. Secondly, the amount of water during mixing needs to minimal: the concrete or cement needs to be just workable, on the dry side even, and not fluid. Thirdly, it is essential that during curing the cement or concrete is kept moist at all times, for at least a week. Structures should be covered with plastic, large leaves or other materials during the curing period, and kept wet regularly.
Simplify construction methods while getting a more robust end product in a safer fashion. Using lining & telescopic lining has the advantage that heavy lifting equipment for pre-cast rings is obsolete while procedures are inherently safer. Lining is made using one-skin moulds that hold concrete against the dug wall of the hole, while the telescopic shaft can be made from curved blocks built onto a foundation cutting ring – the blocks can be extended as and when necessary.
===Costs===
Hand-dug wells can provide a viable alternative to unhygienic, unprotected sources while avoiding the capital and maintenance costs associated with sophisticated drilling programmes or reticulated pumped systems. A range of lining types and water lifting technologies can be chosen to match the financial and management capacity of the participants in the water supply process.
==Field experiences== ==Manuals, videos, and links===
* [http://www.rural-water-supply.net/en/resources/details/256 Hand dug shallow wells (Skat)]. Includes construction information plus covers lining options. Also a good section on environmental, social, and cultural considerations. Swiss Centre for Development Cooperation in Technology and Management.
* [http://www.rural-water-supply.net/en/implementation/hand-dug-wells Hand Dug Wells] section of the Rural Water Supply Network website
* Old style of excavated wells in India: [http://www.greatmirror.com/index.cfm?navid=169 India Themes: Irrigation 1: Ancient Methods.]
===Acknowledgements===
* CARE Nederland, Desk Study: [[Resilient WASH systems in drought-prone areas]] October 2010.
* Collins, Seamus, [http://www.rural-water-supply.net/en/resources/details/256 Hand dug shallow wells (Skat)]. Swiss Centre for Development Cooperation in Technology and Management. 2000.