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沙坝

36 bytes removed, 11:46, 3 September 2015
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After the dam is built, an outlet for water extraction must be constructed for drinking, agriculture, etc. Hand dug scoop holes are the simplest possibility, however the water can easily be contaminated. Covered shallow wells, either with or without [[Handpumps]] or a [[Rope pump]] protect the water much better. It is also possible to construct an outlet pipe with a tap. In certain designs for sand dams, a pipe is shown that takes water by gravity ''through'' the dam wall. These are said to not work well due to either a blocked intake, a broken tap on outlet side and the possibility of weakening the dam wall. Where water is abstracted directly, risk of contamination increases. In such a case, household water treatment should be advocated (e.g. [[Sodis]]). <br> 沙坝竣工后,必须建一个取水出口,用于饮水、农业等用途。用手挖勺洞是最简单的方法,但水容易受污染。有盖浅井,无论带不带有[[手压泵]]或[[拉绳泵]],都可以更好地保护水资源。也可以建造带有龙头出水管来取水。关于沙坝的设计中,水管能运用重力输送水资源''经过''坝墙。据称,由于入水口堵塞或出水口龙头损坏,以及坝墙可能松动,取水管运作不良。而直接抽水的地方,污染的风险会增加。在这种情况下,应该提倡家庭用水的处理(如,[[太阳能消毒]])。<br>
[[Image:Sand dam scoop hole.JPG|thumb|right|200px|Groundwater abstraction from the riverbed by means of a scoop hole. Kitui District, Kenya. Source: 运用勺洞法从河床取地下水。肯尼亚基图伊区。来源: [http://www.sswm.info/category/implementation-tools/water-sources/hardware/precipitation-harvesting/sand-dams HOOGMOED (2007).]]] [[Image:Sand dam well.JPG|thumb|right|200px|Men fetching water using a hand pump from a closed well near a sand dam in Kituï, Kenya. Source: 在肯尼亚基图伊,男子使用手压泵从沙坝附近封闭的井里取水。来源:[http://www.sswm.info/category/implementation-tools/water-sources/hardware/precipitation-harvesting/sand-dams RAIN (Editor) (n.y.)]]]
====Maintenance维护====
If done timely, the maintenance required is not costly. Small malfunctions in the dam however can lead to destruction of the entire dam. Therefore, the dam should be regularly checked for cracks and damage. Particularly after floods, and extreme temperature changes cracks are likely. These need to be repaired as soon as possible by a trained mason. During the dry season, raised-sand dams should be raised by a maximum of 50 cm if the reservoir has filled up.
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