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沙坝
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[[Image:CompletedSandDam.JPG|thumb|right|200px|竣工的沙坝。索马里兰。 Eric Fewster, BushProof / Caritas]]
* Timing is important: dams should be built during the dry season, but don’t build dams too close to the rains in order to avoid the trench filling up with water or the dam being washed away.时间安排很重要：建坝需在旱季进行，且勿太临近雨季，以避免沟渠被水填满或坝体被冲走。
* The method depends on the type of dam and the type of ground. The construction of sand dams in cascades improves total storage and efficiency and minimizes seepage losses. Dams made of concrete, stone-masonry (cheapest and easiest) and brickwork require skilled labour for construction, but are stronger and have a longer lifespan. 建坝方式由水坝类型和地质类型来决定。在梯级地形上建造沙坝能提升总储水量和效率，并将渗流损失降至最低。建坝方式由水坝类型和地质类型来决定。在梯级地形上建造沙坝能提升总储水量和效率，并将渗漏损失降至最低。混凝土、砌石（最便宜、最简单）和砌砖建成的水坝虽然需要熟练工人来建造，但会更坚固，使用寿命也更长。建坝方式由水坝类型和地质类型来决定。在梯级地形上建造沙坝能提升总储水量和效率，并将渗流损失降至最低。建坝方式由水坝类型和地质类型来决定。在梯级地形上建造沙坝能提升总储水量和效率，并将渗漏损失降至最低。混凝土、砌石（最便宜、最简单）和砌砖建成的水坝虽然需要技术娴熟的工人来建造，但会更坚固，使用寿命也更长。
* Usually sand dams are built onto a rock layer, but where there is no rock and only clay, it can still work but as long as the foundation is keyed into the clay layer and where the wall does not protrude more than 0.5m above original sand level, otherwise there is a risk the structure overturns during a flood event.通常，沙坝要建在岩层上，但在没有岩石而只有黏土的情况下，只要地基能嵌进黏土层，且坝墙不超出原有沙层0.5米，沙坝仍能运行；否则在洪水期间，坝体有倾覆的危险。
* Key into banks or construct wing walls to avoid erosion around edges of the sand dam. Where wing walls are built, a good technique is to start with the wing walls and work inwards to the centre, since community enthusiasm lags by the time wing walls are constructed (if not built first), yet they are essential to proper functioning. Length of the wing wall varies according to bank characteristic: loose riverbanks, 7 metres; hard soils, 5 metres; hard & impermeable soils or rocks, wing wall is not needed. Planting napier grass along upstream riverbanks controls erosion and fixes the course of the river in a flood.坝体需嵌入河堤，或建造翼墙来防止沙坝边缘侵蚀。建造翼墙的情况下，较好的方法是先从翼墙开始建造，然后向中心动工。如果不先建造翼墙，社群的建造热情会在翼墙竣工前就下降，而翼墙对沙坝的正常运作来说至关重要。翼墙的长度随河堤的特性而定：松散的河堤，7米；硬质的土壤，5米；不透水且硬质的土壤或岩石则不需要翼墙。在上游河堤种植象草可以控制侵蚀，并在洪水中修正河道。
Further, the outlet and upstream riverbed should be cleaned regularly to make sure the dam does not get blocked. Silt, rocks, dead animals, etc. should be removed regularly. This can also help prevent contamination of the water. The quality of the water in the well should be checked, once in a while, by an expert. 而且，出水口和上游河床需要定期清理，确保沙坝不会堵塞。淤泥、石块和动物死尸等需要定期清除。这也能帮助防止水污染。井中的水质需要间或由专家进行检查。
Maintenance can normally be carried out by the users of the system or by a caretaker or watchman. Larger repairs may require skilled labour, which can usually be provided by local craftsmen. In some cases, unskilled labour may be required on a large scale (e.g. for repairing a broken raised-sand dam, or a leaking subsurface dam). The labour may be provided by the users (with or without pay), or by other people who are hired for the purpose.一般可以由沙坝系统使用者、管理员或看守人来实施维护工作。较大的修补工作可能需要技术娴熟的工人来进行，通常可以找当地的工匠。有些情况下，大规模的修补也会需要非技术工人（如，修补已提高过的故障沙坝，或渗漏的地下水坝）。可以由沙坝使用者提供劳动力（有或没有薪酬），或雇佣其他人来修补。
Users may need to establish a local committee to manage issues, such as controlling or supervising water use, preventing water contamination, carrying out O&M activities, financing O&M, and monitoring how much stored water is still available (a piezometer or auger hole may be installed to allow a caretaker or watchman to estimate how much water is left and decide if rationing has to be introduced). Proper management may also help to prevent social conflict. For O&M tasks at the dam site, a person who lives or farms near this site could be appointed. This person could also be responsible for water allocation and be involved in monitoring activities, if users obtain the water near to, or at, the site. His or her authority should be clear and accepted by all users.
