Status and challenges of water resources and supply in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) of China.

The Guangdong-Hong Kong-Macao Greater Bay Area (GBA) is one of the most economically developed regions in China. To support the highly developed socioeconomical activities, the water demand in the GBA is in large amount and outstrips supply. Therefore, water resources in the GBA are under serious pressure. In this study, the supply, utilization, treatment, and reuse of water in the GBA were surveyed. Most cities in the GBA, face severe water shortage with per capita water resources being lower than the threshold of severe water scarcity (500 m³). During 2011-2020, the water consumption per 10,000 yuan of gross domestic product (GDP) of the GBA, decreased by 58%, showing an increased water utilization efficiency. The water quality was consecutively increased in recent years in the GBA with pollution-induced water shortage decreased and most drinking water sources meeting the Class III water quality standard. The utilization rate of reclaimed water varies greatly within the region, which is closely related to the degree of economic development and the amount of water resources. Besides, reclaimed water is mainly used for recharging water environment in the GBA, with unrealized potential in the industrial and municipal fields. It has been reached a consensus that water shortage would be one critical factor limiting the sustainable development of the GBA. To solve all facing challenges, the following strategies are proposed: 1) design urban development paths based on water resources; 2) promote the use of reclaimed water and other non-conventional water resources; 3) promote the construction of sponge cities. [ABSTRACT FROM AUTHOR]