Assessing Climate-Induced Risks to Critical Energy Infrastructure: A Comparative Analysis of Hydropower and Oil and Gas Systems in Drought-Prone U.S. Regions

Climate change poses escalating threats to energy infrastructure in the western United States, yet the interdependencies between affected sectors remain insufficiently characterized. This study develops a comparative, empirically informed framework for understanding how drought transfers vulnerability across hydropower and oil and gas systems. Drawing on the IPCC vulnerability assessment approach, cascading-risk perspectives, and socio-technical systems theory, the study advances four hypotheses regarding mechanisms of drought-induced cross-sector vulnerability transfer. Through a structured comparative synthesis of generation data, reservoir levels, water consumption records, and emissions inventories across the western United States (2001-2024), the analysis documents that hydropower facilities have experienced cumulative generation declines of up to 23% since 1980 (Turner et al., 2024), with individual drought years producing output reductions of 48-81% at major facilities. Simultaneously, hydraulic fracturing water use per well has increased up to 770% (Kondash et al., 2018), predominantly in high water-stress regions. The assembled evidence is consistent with a cascading dynamic in which hydropower shortfalls necessitate fossil fuel substitution, which amplifies water demand and emissions, potentially reinforcing drought conditions. Published estimates attribute approximately \$20 billion in monetized damages to this mechanism over 2001-2021 (Qiu et al., 2023). The analysis further suggests that threshold effects in reservoir levels may intensify cross-sector stress nonlinearly. The study proposes integrated adaptation pathways bridging water, energy, and climate governance, and identifies priorities for future empirical and modeling research.