Tucson receives an average of 12 inches of rain a year (about six inches during the summer monsoons and another six inches during the winter rains). While native flora has adapted to survive with minimal water, fruit trees and other edibles often struggle to remain healthy in the desert valley, especially during periods of drought.

Rainwater cisterns capture roof runoff and stores it for use during the dry periods of the year, where access to non-municipal irrigation water is limited. A rainwater cistern collecting runoff from a 2,000 sf surface will harvest an average of approximately 12,000 gallons per year (enough water to support two adult citrus trees). When these cisterns reach full capacity, excess water is directed out to the nearest rain garden or drainage way.