Approach for Estimating Available Consumable Water for Human Activities in a River Basin

Water is vital for economic development and environmental sustainability in arid and semi-arid basins. Management of water resource requires good understanding of available water for human consumption. Evapotranspiration (ET) is an important component of the hydrological cycle and represents the amount of water lost to the atmosphere in a basin. This study proposes a new approach to estimate available consumable water for human activities (ACW) in a basin based on precipitation, natural ET, and uncontrollable outflow, thus capping water use for human consumption in a basin. The ACW is illustrated for the Hai Basin in North China, where the average ACW from 2001 to 2012 for the entire basin is estimated at 31.97 × 10⁹m³ yr.⁻¹, varying between 18.61 × 10⁹m³yr⁻¹ in 2002 and 42.60 × 10⁹m³yr⁻¹ in 2003. A water balance analysis for the basin indicates that the aquifer water depletion in Hai Basin for 2001–2012 is 5.23 × 10⁹m³yr⁻¹. Compared to existing water resources assessment, ACW provides an easier approach to water management planning as no hydrological data are required, only data on precipitation and ET, supported by landcover data.