The Jiama copper polymetallic mine, one of China’s highest⁃altitude and largest porphyry coppermines, faces dual threats of concealed water⁃conducting structures and karst fissure water as mining depths exceed4 300 m. This study optimizes the application of dynamic transient electromagnetic（TEM）detection technology for themine and systematically develops precise detection methods for concealed water hazards. By analyzing the characteristicsof concealed water hazards, forward models of typical aquifers were established, and 3D numerical simulations wereconducted to investigate induced electric field propagation and response characteristics. The dynamic TEM imagingalgorithm was improved to achieve high⁃precision, real⁃time interpretation of underground TEM signals. Parameter testsinvolving different coil configurations, transmitting currents, stacking numbers, and detection frequencies were carriedout to determine the optimal detection parameters for the Jiama copper polymetallic mine. Field tests demonstrated thatthe technology enabled accurate extraction of low⁃resistivity anomalies（apparent resistivity <6 Ω·m）within high⁃resistivitysurrounding rock backgrounds, rapidly locating concealed water hazards. The results provide a robust geological safeguardfor safemining operations at Jiama copper polymetallicmine and open new avenues for water hazard prevention and control.