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[[Image:check dams (gully plugs) icon.png|right]]
[[Image:check dam india.jpg|thumb|right|300px200px|Check Dam for Rainwater Conservation. NMDC Diamond Mine, Panna, Madhya Pradesh. Photo: [http://greenfieldeco.com/photogallery.php Greenfield Eco Solutions Pvt. Ltd.]]]
A check dam is a small, temporary or permanent dam constructed across a drainage ditch, gully, swale, or channel to lower the speed of concentrated flows (like an overflow weir) for a certain design range of storm events. They may be more categorized as a type of floodwater rather than a runoff harvesting technique. A check dam can be built from logs of wood, stone, pea gravel-filled sandbags or bricks and cement. They have been used widely in Kenya and India. These dams can also be made as [[leaky dams]]. Dams that have been built in riverbeds with no coarse sand transport ([[Sand dam]]s) may end up being used in this way. These structures are relatively cheap and can last about 2-5 years.
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! width="50%" style="background:#efefef;" | Advantages
! style="background:#ffdeadf0f8ff;" | Disadvantages
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| valign="top" | - Water speed is slowed, which reduces erosion and prevents unwanted gully formation during a flood <br>
==Resilience to changes in the environment==
[[Image:EthiopianGullyPlug.jpg|thumb|right|300px200px|Rehabilitated gully in Adaga Lemne watershed, Axum, Tigray Province. Photo: Johan Rockstrom.]]
====Drought====
'''Effects of drought''': Lower crop yields.<br>
'''Specific advice''':
[[Image:CementCheckDam.jpg|thumb|right|300px200px|Drawing: [http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CFkQFjAB&url=http%3A%2F%2Fwww.saiplatform.org/uploads/Modules/Library/SAI%2Fuploads%2FModules%2FLibrary%2FSAI%2520Technical20Technical%2520Brief20Brief%25205205%252020%2520The20The%2520Importance20Importance%2520of20of%2520Soil20Soil%2520to20to%2520Water20Water%2520Use20Use.pdf&ei=gf91T6GYJ-jWiAK7zuGnDg&usg=AFQjCNFDyR4mjTVCcvvTt-9v4OrxAZQfDA&sig2=iMzgbW0eK395na_V_YA4Kw Water Conservation Technical Briefs.] SAI.]][[Image:WoodenCheckDam.jpg|thumb|right|300px200px|Cross section of wooden check dam. Overtop "pour spout" must be included. <br> Drawing: [http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CFkQFjAB&url=http%3A%2F%2Fwww.saiplatform.org/uploads/Modules/Library/SAI%2Fuploads%2FModules%2FLibrary%2FSAI%2520Technical20Technical%2520Brief20Brief%25205205%252020%2520The20The%2520Importance20Importance%2520of20of%2520Soil20Soil%2520to20to%2520Water20Water%2520Use20Use.pdf&ei=gf91T6GYJ-jWiAK7zuGnDg&usg=AFQjCNFDyR4mjTVCcvvTt-9v4OrxAZQfDA&sig2=iMzgbW0eK395na_V_YA4Kw Water Conservation Technical Briefs.] SAI.]]
The sides of the check dam must be higher than the centre so that water is always directed over the centre of the dam (this avoids the dam being outflanked by the flow).