A Comprehensive Review on Blockchain-based Systems for Groundwater Conservation and Wastewater Management.

Groundwater conservation and wastewater management soil depletion, water pollution, and poor resource management. These problems underscore the need for innovative practices that leverage blockchain technology to enhance sustainability, maintain data integrity, and optimize resource utilization in wastewater management. This review systematically analyzes recent advances (2019-2025) in blockchain technology, Machine Learning (ML), and Deep Learning (DL) models applied to sustainable water resource management. The objectives are to evaluate technological integrations, quantify performance improvements, and identify research gaps and future directions. Methodologies include a comprehensive review of 97 peer-reviewed articles focused on the integration of technology in water resource management. The review highlights benefits such as improved data validation, resource optimization, and transparency. Crucial applications include anomaly detection, groundwater recharge estimation, and regulatory compliance through blockchain-enabled secure data management. Technological contributions from smart sensors, internet of things-based real-time monitoring, Artificial Intelligence (AI)/ (ML) forecasting models, and advanced analytics collectively support more resilient and sustainable wastewater management practices. Key quantitative findings include predictive accuracy improvements up to 86%, wastewater treatment efficiency gains of 20%, and enhanced resource allocation through blockchain's decentralized frameworks. Despite these advances, challenges remain in data integration, scalability, and regulatory adoption, suggesting future research focus on integrating smart contracts, real-time monitoring systems, and internet of things-based governance frameworks to further enhance efficiency and compliance.