Rain barrels are low-cost, effective, and easily maintainable water conservation devices. They help prevent stormwater pollution by reducing the amount of water that reaches our storm drain system. By storing and diverting rainfall runoff from roofs, these devices reduce the undesirable impacts of storm drain overflows such as flooding, erosion problems in creeks, and water pollution. Due to their relatively small volume, Rain barrels are commonly used as a secondary source of water for landscape irrigation in residential areas. If larger water storage capacities are desired, cisterns can also be used to collect rooftop runoff.
Rain barrels can provide a source of chemically untreated 'soft water' for gardens and compost, free of most sediment and dissolved salts. Because residential irrigation can account for up to 40% of domestic water consumption, water conservation measures such as Rain barrels can be used to reduce the demand on the municipal water system, especially during dry summer months. Rain barrels have also been found to be an easy solution to gutter system blockages, and similar home improvement projects.