Rainwater tank

A rainwater tank is a water tank used to collect and store rain water runoff, typically from rooftops via pipes. Rainwater tanks are devices for collecting and maintaining harvested rain. A rainwater catchment or collection system can yield 1,000 litres (260 US gal) of water from 1 cm (0.4 in) of rain on a 100 m2 (1,100 sq ft) roof.

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