Abstract: Aging dams, which have served societies for decades, are vulnerable to various anthropogenic and natural environmental factors, leading to potential safety hazards on their surfaces or within their structures. The manifestation of such hazards could result in substantial socio-economic losses. Accordingly, dam safety inspection techniques including geophysical prospecting, tracer methods, hydrogeological surveys, numerical simulation, and hydrochemical isotope analysis have evolved significantly. This paper reviews the historical development, current research focus, and emerging challenges in global dam inspection techniques, summarizes the effectiveness and limitations of existing methods, and proposes an integrated interdisciplinary approach that combines non-destructive testing with water-body detection techniques, supported by case studies. The proposed approach can provide multi-faceted insights into the sources, connectivity, and dynamics of water within and around dams, thereby enhancing the accuracy of structural inspections and offering technical support for safety monitoring in water conservancy engineering and geotechnical investigations.