NTC18 time-adaptive PSHA reliability for Poisson predictions of Camastra dam multi-risk scenarios

We propose a time-adaptive seismic reliability framework consistent with NTC18 code to evaluate infrastructure performance under multi-risk conditions, combining Poisson-based probabilistic seismic hazard assessment (PSHA) with non-seismic environmental and other regulatory uncertainty drivers. The method is applied to the Camastra Dam in Southern Italy, historically affected by structural limitations, lack of updated seismic and hydraulic assessments, and restrictive rules imposed without supporting retrofitting. This framework allows comparison between long-term earthquake-induced collapse probabilities and the short-term escalating risk of total storage loss under precautionary management. The results highlight how unbalanced risks estimates can compromise the resilience of water infrastructure under compound threats.