The more wastewater reclamation, the less water stress?

Abstract

Wastewater treatment removes water pollutants and wastewater reclamation provides an alternative water supply. It is believed that increasing the rate of wastewater reuse and reclamation can reduce water stress. This study aims at understanding whether reusing more wastewater can help mitigate water stress in China. Through scenario analysis, it is found that the potential for reuse of reclaimed water under a water conservation scenario is only 12-56% of the actual situation, but regional water stress under a water saving scenario is 10-82% lower than the current reality. The results show that a higher amount of reclamation does not necessarily lead to a lower water stress in one region. The potential for wastewater treatment and reuse is determined by return flows, which can reduce water use efficiency and exacerbate water stress. To effectively alleviate water stress, it is important to not only increase wastewater reuse, but also prioritize water conservation.