<p>Groundwater, the largest accessible freshwater reserve, is increasingly threatened by the simultaneous presence of pathogenic microorganisms and toxic chemical pollutants, posing substantial risks to public health and ecosystem stability. While numerous studies address individual contaminants categories, integrated evaluation of microbial and chemical threats alongside sustainable treatment strategies remain limited. This review provides a comprehensive synthesis of contaminant sources transport mechanisms, survival dynamics and associated health burdens, highlighting the global scale of groundwater-related disease outbreaks and chronic toxicity risks. A critical comparative assessment of low-cost and sustainable remediation technologies including biological treatment systems, adsorption-based materials, permeable reactive barriers, membrane distillation, and electrocoagulation is presented. Key finding indicate that adsorption and bio-based system demonstrated high removal efficiencies (&gt; 90% in several reported cases) with lower operational costs, while hybrid and passive technologies offer enhanced long-term sustainability for decentralized settings. The review identifies scalability, site-specific hydrogeological variability and lifecycle cost optimization as major research gaps. By linking treatment performance with risk-based management and Sustainable Development Goals (SDG 3 and SDG 6), this work advances an integrated framework for resilient and affordable groundwater restoration. Furthermore, the study highlights the need for hybrid treatment platforms and real-time monitoring integration to bridge laboratory innovations with field-scale implementation. Strengthening interdisciplinary collaboration is essential to translate technological advances into practical, policy-relevant groundwater solutions.</p> Graphical abstract <p></p>