The Importance of Nonconventional Water Resources under Water Scarcity

According to FAO, water scarcity is now affecting all five continents and is expected to intensify in the coming years as the water demands of the growing population increase and the impacts of climate variability become more pronounced. The existing unevenness of water resource availability and insufficient investment in relevant infrastructure have forced the water sector to recognize the importance of nonconventional water resources (NWR) in planning for a sustainable water future. The purpose of this review is to highlight the available and potentially available NWR and to discuss the future application of these water sources.