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Sand dams require careful maintenance, and immediate repair, as flooding causes hundreds of tons of water to fall over the dam wall and onto the spill-over apron. Flood water may also spill over and erode the wing walls and, perhaps, even over the riverbanks during heavy rains. When determining the dam and spillway height at the selected location, it is very important that the water level and flood line remain below the riverbanks after construction of the dam, or that flooding will not lead to problems up or downstream of the dam. If the flood level is higher than the riverbanks, construction of a dam is not advisable.
===Constructionविनिर्माण, operations and maintenanceपरिचालन और रखरखाव===
[[Image:Sand dam diagram.JPG|thumb|right|200px|Cross section of a sand dam.<br> Diagram: Netherlands Water Project. <br>Click image to see details.]]
[[Image:Sand dam trench.JPG|thumb|right|200px|People excavating a trench. Source: [http://www.sswm.info/category/implementation-tools/water-sources/hardware/precipitation-harvesting/sand-dams RAIN (n.y.)]]]
====Building the sand dam रेत बंध (and wing wallऔर साथ की दीवार)का निर्माण===='''General advice on cementसीमेंट को लेकर आम सलाह:''': A common cause of cracks in structures and linings (e.g. in tanksटैंक, damsबांध, waterways, wells) is errors in mixing and applying the cementजलाशयों और कुओं आदि में दरार की एक आम वजह है सही मिश्रण और सीमेंट का सही इस्तेमाल न करना. सबसे पहले यह बात अहम है कि शुद्घ सामग्री का प्रयोग किया जाए. First of all, it is important that only pure ingredients are usedयानी : clean waterसाफ पानी, clean sand, clean rocksसाफ चट्टानें आदि. सामग्री को भलीभांति मिलाया जाए. पानी का कम से कम इस्तेमाल किया जाए. The materials have to be mixed very thoroughlyसीमेंट यथासंभव सूखे रूप में प्रयोग की जाए. 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 fluidयह जरूरी है कि तरावट के समय सीमेंट या कंक्रीट में लगातार नमी बनी रहे. Thirdly, it is essential that during curing the cement or concrete is kept moist at all times, for at least a weekकम से कम एक सप्ताह तक उसका नम रहना जरूरी है. Structures should be covered with plastic, large leaves or other materials during the curing periodढांचे को तराई के दौरान प्लास्टिक, and kept wet regularlyबड़ी पत्तियों या अन्य सामग्री से ढककर रखना चाहिए.
'''विशिष्ट सलाह'''