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Riverbed hand-dug wells

1 byte removed, 12:08, 23 April 2012
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These are shallow wells which draw water from a natural or man-made aquifer specifically within a riverbed. The simplest version of these is a shallow hole dug every season in a riverbed which gets flooded with every flood event. Other versions allow the water to be accessed all year round through [[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.
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{{Climate_change
|heading1=Drought
|text1= '''Effects of drought''': Can dry up. <br> '''Underlying causes of effects''': Less recharge of aquifer due to less rainfall; Increasing population & water demand; Size of aquifers – e.g. limited sand volume; Wells not sunk deep enough into water table; Incorrect siting; Graded gravel around pipe not correctly done. <br> '''To increase resiliency of WASH system''': Increase volume through construction of groundwater dam; Sink wells/pipes deeper; De-water wells during caissoning within the water table; Construct during the latter half of the dry season; Site in riverbeds that are dry for part of the year, where water remains in the riverbed throughout the dry season; Increase flow by use of porous concrete & perforated pointed steel pipes driven horizontally into the aquifer (riverbed wells) and graded gravel (infiltration galleries & jetted wells); Site in a degrading river section where there is no deposition (infiltration galleries); Put graded gravel around pipes to minimize clogging and increase flow.
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==Suitable conditions==
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