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[[Image:BareRockCatchment.jpg|thumb|right|300px|Natural rock catchment on Sullivan Rock, USA. <br> Photo: [http://bibbulmuntrack1000.blogspot.com/2010/09/5th-training-324-km-5-days-walk.html Paul Madden.]]]
[[Image:RockCatchment.jpg|thumb|right|300px|Rock catchment project in Kitui, Kenya. <br> Photo: [http://www.friendsofkitui.com/rockcatch.htm Friends of Kitui.]]]
==Suitable conditions==
* The rock that makes up the catchment should be bare and free of vegetation/soil. It should have no fractures or cracks that would result in a loss of water through seepage.
* Site the dams for rock catchments to maximize the natural topography – to get the best storage volume, build on gorges between rocks, rock pools, and rock shelves. Make dams on the lower side of existing rock pools.
- Tanks and masonry dams provide domestic water, but are not capable of supplying water for livestock or irrigation due to their high demands.
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==Resilience to changes in the environment==
====Drought====
'''Effects of drought''': Tend to dry up quickly.
'''Underlying causes of effects''': Lack of rainfall.
'''To increase resiliency of WASH system''': Site on rock that is bare and free of vegetation/soil with no fractures, so whatever amount of rain ''does'' fall, it will have a greater chance of being collected.
==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:RockCatchmentRoof.jpg|thumb|right|300px|Building a roof for the rock catchment dam to keep it clean and minimise evaporation losses.<br> Photo: [http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0CDcQFjAC&url=http%3A%2F%2Fwww.samsamwater.com%2Flibrary%2FBook1_Water_from_Rock_Outcrops.pdf&ei=Ys59T4_iLanM2gXA4NTlDA&usg=AFQjCNFY-XFDfUONAlG7HCp0p7Q4YDDOhw&sig2=UKAZc-rFHN-M4tfVsNOZGQ Water from Rock Outcrops.] DANIDA.]]
[[Image:RockPool.jpg|thumb|right|300px|A rock pool in near Taveta, Kenya.<br> Photo: [http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0CDcQFjAC&url=http%3A%2F%2Fwww.samsamwater.com%2Flibrary%2FBook1_Water_from_Rock_Outcrops.pdf&ei=Ys59T4_iLanM2gXA4NTlDA&usg=AFQjCNFY-XFDfUONAlG7HCp0p7Q4YDDOhw&sig2=UKAZc-rFHN-M4tfVsNOZGQ Water from Rock Outcrops.] DANIDA.]]