Cistern

This article is about water storage tanks. For other uses, see Cistern (disambiguation).

Portuguese cistern (Mazagan), El Jadida, Morocco (1514)

The difference between a cistern and a well is in the source of the water: A cistern collects fresh water where a well draws from groundwater.

A cistern (from Middle English cisterne; from Latin cisterna, from cista 'box'; from Ancient Greek κίστη (kístē) 'basket') is a waterproof receptacle for holding liquids, usually water. Cisterns are often built to catch and store rainwater. To prevent leakage, the interior of the cistern is often lined with hydraulic plaster.

Cisterns are distinguished from wells by their waterproof linings. Modern cisterns range in capacity from a few liters to thousands of cubic meters, effectively forming covered reservoirs.