The Guangdong-Hong Kong-Macao Greater Bay Area is a strategic pivot for China in accelerating the establishment of a new development paradigm. It is therefore imperative to improve the optimal allocation of water resources and provide high-quality water supply security in support of high-quality economic and social development. With the implementation of new water governance concepts

including rigid constraints on water resources and the principle of “development based on the carrying capacity of water resource”

together with the accelerated development of key national water network projects such as the Datengxia Water Control Project and the Pearl River Delta Water Resources Allocation Project

both the requirements for and the external conditions of water supply security in the Greater Bay Area have undergone profound changes. It is therefore necessary to improve understanding

accurately identify key issues

and put forward effective solutions.Based on a systematic analysis of the current status

evolving situation

and challenges of water supply security in the Greater Bay Area under the background of water network development

and oriented toward technical demands

this paper discusses the major technical bottlenecks that urgently need to be addressed

including forecasting and early warning of extreme drought and salinity intrusion events

assessment and regulation of the spatial equilibrium of water resources

and joint operation of water network projects. It further elaborates on how to effectively enhance water supply security in the Greater Bay Area through measures such as advancing water network construction

strengthening unified basin-wide operation

and developing a digital twin water network. The study can provide a useful reference for the operation and management of regional water network projects

the research and development of key technologies

and water security assurance in the Guangdong-Hong Kong-Macao Greater Bay Area.