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Handpumps

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[[Image:Handpump.jpg|thumb|right|400px|Liquid Gold - Children in the Central African Republic pump clean water from underground. Photo: Marielle van Uitert.]]

Many different kinds of handpumps are frequently installed on hand-dug wells and boreholes in rural areas, including many drought-prone areas. They facilitate a contamination-free method to extract water.

==Suitable conditions==

~~{{Climate_change~~

~~|heading1=Drought~~

|text1='''Effects of drought''': Handpumps not repaired (weak effect?) <br> '''Underlying causes of effects''': Lack of household finance to contribute to repairs due to suffering household economy. <br> '''To increase resiliency of WASH system''': Choose simple technologies; Consider handpumps where a viable sustainable handpump option has been shown to work in an area; Promote increased levels of ownership & responsibility.

~~|heading2=Drought effects on cement~~

|text2='''Effects of drought''': Badly made concrete or cracked linings (e.g. in tanks, dams, waterways, wells, and other structures). <br>'''Underlying causes of effects''': Less water used for curing; Impure water used for mixing. <br>'''To increase resiliency of WASH system''': Ensure adequate mixing, ratios, purity of ingredients; Minimize water content in mixture; Ensure adequate curing.

}}

Overall, it seems sensible that handpumps should be installed only when a viable sustainable handpump option has been shown to work in the area. Depending on pump standardization in country and depth to water table, it is preferable to choose simple technologies that do not need specialist parts and that are repairable locally. The rural poor prefer in any case to have cheaper, shorter-life technologies despite the need to maintain them more frequently.

==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.

'''Specific advice''':

[[Image:DirectActionHandpump.jpg|thumb|right|300px| Direct action handpump mechanics.]]

There are many different types of handpumps. However most of them are positive displacement pumps and have reciprocating pistons or plungers. There are suction pumps, low lift pumps, direct action pumps, intermediate life pumps, and high lift pumps. For details on these types, look them up in [http://www.wateraid.org/uk/what_we_do/sustainable_technologies/technology_notes/244.asp Technology notes: Handpumps] (by WaterAid).

Marktielewestra

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