Multi-Hazard Reliability of Reservoirs, Aquifers, and Springs in Basilicata under Snow Drought and NTC18 Regulations

The prolonged 2023–2026 drought has exposed critical vulnerabilities in the hydro-infrastructural systems of Southern Italy, where drinking water supply depends on a coupled network of snow-fed reservoirs, spring systems, and karst aquifers. This contribution proposes a multi-hazard analytical framework that links snow drought, hydrogeological deficit, and storage infrastructure reliability, expanding beyond the well-documented Camastra Dam case to include the critical behavior of the Val D’Agri, Fossa Cupa and other regional aquifers. Using drought-propagation models, remote sensed data, and high-resolution in-situ datasets, we analyze how snow-pack deficits propagate through surface reservoirs and karst systems with different lag times, generating asynchronous yet convergent supply failures. The 2019 Camastra Dam’s forced drawdown and 2024 crisis—driven by NTC18 seismic design-reliability regulations, outlet malfunction, and reduced inflow—served as a “early system-scale indicator,” anticipating district-level shortages later confirmed by declining groundwater heads and reduced spring discharge across the southern Apennines. 
Building on these observations, this study proposes a unified reliability framework that integrates: (1) climate drivers (snow drought, reduced recharge), (2) hydrogeological pathways (karst storage, delayed meltwater propagation), (3) infrastructure performance and regulatory constraints (NTD14, NTC18 and related design requirements, outlet failures, storage restrictions), and (4) operational risk for drinking-water districts in Basilicata, Puglia, Campania. Preliminary results reveal the emergence of a system-wide tipping condition in which both reservoirs and karst springs lose buffering capacity—an unprecedented scenario for Southern Italy.