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Concrete production and drought

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[[Image:breaking-stones-for-concrete.jpg|thumb|right|300px|Breaking stones to make aggregate for concrete in Uganda, East Africa. [http://polishingpeanuts.com/02/2011/photos-from-uganda-lost-and-found/ Polishing Peanuts blog.]]]
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Poor construction techniques are to blame for many leaking water structures, which in turn affects water availability. Key construction issues such as the making of concrete, correct construction of stone masonry, as well as the issue of pipes passing through water-bearing structures. This section focuses on concrete making. Proper techniques are often bypassed or shortened, which increases the risk of failure and reduces the life of the structures. This is especially true in many drought-prone areas that have dry climates and where water is at a premium, since it affects the essential curing process.
===Construction, operations and maintenance===
====Use high quality ingredients====
Ensure adequate curing - this is one of the most important aspects to making strong concrete, but is often bypassed in the field due to lack of water, knowledge or organization. Adequate curing is necessary to keep the process of hydration going as long as possible – the longer the time, the stronger the concrete. This hydration process will stop once the concrete has dried out, resulting a strength of concrete according to the time of curing. Although curing can continue even for years, 7 and 28 days are normally quoted (see graph) – curing should last at least 7 days, if not longer especially in cold weather. Curing involves sprinkling water on the concrete every day as well as covering it, preferably in a shady area. Covering can be done with material like plastic or sacking, but covering in wet sand also works well, as does putting the concrete entirely in water.
===Reference manuals, videos, and links===
* Concrete poker vibrator (commercial product). Found at [http://www.alibaba.com/showroom/portable-concrete-poker-vibrator.html Alibaba.com.]
* Video: [http://www.howcast.com/videos/155401-How-To-Mix-Concrete-By-Hand How to mix concrete by hand.]
===Acknowledgements===
* CARE Nederland, ''Desk Study Resilient WASH systems in drought prone areas.'' October 2010.
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