Self-sufficiency of urban water in non-drinking uses by rainwater extraction method in Aryan Shahr, South Khorasan

Rainwater harvesting is one of the available, low-cost, and complementary methods for groundwater use, which is highly important in arid and semi-arid regions. The purpose of this study is to estimate the amount of water that can be extracted from the annual rainfall of Aryan Shahr for non-drinking purposes. In this study, in the first stage, the rainfall data of the Aryan Shahr climatology station, located in the city, for the period 1975-2016 were studied and analyzed and the average rainfall of Aryan Shahr was calculated to be 183 mm. In the second stage, based on detailed studies of Aryan Shahr municipality, the amount of the city area, as well as different uses of the city, was determined, and based on the runoff coefficient of each user, the volume of extractable runoff was determined on a monthly, seasonal, and annual basis. The results of this study showed that due to the occurrence of precipitation in winter and spring, the maximum volume of water can be extracted from December to April, and seasonally in winter and spring can be extracted. Annually, the amount of 141636.2 cm3 of runoff can be extracted from the city, which can be used in various applications according to the needs of the city.