Sustainable development necessitates the comprehensive management of water resources in light of diminishing supply and increasing demand. This review examines new developments in methods, instruments, and policies to deal with issues brought on by population expansion, urbanization, and climate change. It starts by looking at water conservation techniques, such as leak detection devices, intelligent irrigation systems, and rainwater harvesting, which maximize home, commercial, and agricultural usage and support water sustainability. It discusses advanced technologies in wastewater treatment, like membrane filtration and decentralized systems, improving water quality and enabling the reuse of treated wastewater. This review highlights innovative approaches to governance and policy, such as integrated frameworks and stakeholder engagement strategies, ensuring equitable resource allocation. Additionally, it investigates how artificial intelligence, remote sensing, and data analytics may improve water management techniques by enabling real-time monitoring and predictive modelling for well-informed decision-making. Integration and innovation are crucial for addressing water scarcity, pollution, and access disparities and building resilient water systems for present and future generations.