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[[Image:riverbed infiltration galleries icon.png|right]]

Channels take water from a riverbed to a collector well in the riverbank. They are often screens (slotted or perforated pipes) that are inserted horizontally into a riverbed, but also infiltration galleries can be made from channels with graded gravel as long as sediments are not washed into the collector well. Where screens are used, the screen diameter tends to be larger than that used normally for jetted/driven wells.

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! width="50%" style="background:#efefef;" | Advantages

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| valign="top" | - Allows a method of water extraction where sand depth is shallow or where sediments are fine and have low permeability <br>

'''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.

====How deep is the water table?====

Below is an example of the costs of labour, materials, and transportation to install a river infiltration system. Currency is in the Kenyan shilling. 100 Ksh = 1.20 USD.<br>

[[File:InfiltrationPipeCosts.jpg]]