Cistern

A cistern (Middle English cisterne, from Latin cisterna, from cista, "box", from Greek κίστη kistê, "basket") is a waterproof receptacle for holding liquids, usually water. Cisterns are often built to catch and store rainwater. Cisterns are distinguished from wells by their waterproof linings. Modern cisterns range in capacity from a few litres to thousands of cubic metres, effectively forming covered reservoirs.

Waterproof lime plaster cisterns in the floors of houses are features of Neolithic village sites of the Levant at, for instance, Ramad and Lebwe, and by the late fourth millennium BC, as at Jawa in northeastern Lebanon, cisterns are essential elements of emerging water management techniques in dry-land farming communities.

In the Middle Ages, cisterns were often constructed in hill castles in Europe, especially where wells could not be dug deeply enough. There were two types: the tank cistern and the filter cistern. Such a filter cistern was built at the Riegersburg in Austrian Styria, where a cistern was hewn out of the lava rock. Rain water passed through a sand filter and collected in the cistern. The filter cleaned the rain water and enriched it with minerals.

Cisterns are commonly prevalent in areas where water is scarce, either because it is rare or has been depleted due to heavy use. Early on, the water was used for many purposes including cooking, irrigation, and washing. Present day cisterns are often used only for irrigation due to concerns over water quality. Cisterns today can also be outfitted with filters or other water purification methods when the water is intended for consumption. It is not uncommon for a cistern to be open in some manner in order to catch rain or to include more elaborate . It is recommended in these cases to have a system that does not leave the water open to algae or to mosquitoes, which are attracted to the water and then potentially carry disease to nearby humans.

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