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==Suitable conditions==
Good practice is similar to that for a [[sand dam]].
* Ensure they are not built in an area where water will bypass the structure. Riverbanks should be equal in height and tall enough (height of dam + height of flood +10%), and dam should not be constructed near the bend in a river.
- Can be expensive: a 5-step dam, 4.9 metres high, costs around $26,000 to construct
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==Resilience to changes in the environment==
====Drought====
'''Effects of drought''': Less water stored behind dam.
'''Underlying causes of effects''': Less recharge.
'''To increase resiliency of WASH system''': Reduce water loss behind by using adjustable sheets filled with small size gravel on the upstream side of the dam.
====Floods====
Leaky dams are meant to handle flash flood rain events. Very intense rain events could provide faster erosion or carry sediment loads beyond the dam (contrary to the dam's purpose of filtering silt). Or if the rain is slow and long, greater water amounts could add greater silt behind the dam in a shorter amount of time, which may clog the ability of the dam to do direct groundwater recharge. In these cases, more attentive maintenance is required to check for erosion and silt build ups (or escapes).
==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:LeakyDam2.jpg|thumb|right|350px|'''Leaky dam.''' Balochistan, Pakistan. Facing downstream. <br> Photo: [http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CDgQFjAB&url=http%3A%2F%2Funesdoc.unesco.org%2Fimages%2F0014%2F001438%2F143819e.pdf&ei=uqt8T9_sL6ibiQKTqdzFDQ&usg=AFQjCNFjJrN8OJHYuNSZrDZIrDtZxc_LRg&sig2=J7p3YnDub8Ixn2n4DU-uBw ''Strategies for Managed Aquifer Recharge (MAR) in semi-arid areas.''] UNESCO.]]
Similar construction as [[sand dam]]s: