Currently, a critical gap exists in analyzing water system reliability over a projected period of two to five years. This project leverages existing research at the University of Utah to study the impacts of interconnected changes due to climate variability on water supply, demand, and water system reliability with the Salt Lake City Department of Public Utilities (SLCDPU). It builds on years of partnership working with the SLCDPU personnel to conduct climate impact assessments and develop adaptation measures. Working with SLCDPU, the real-world implications of projected conditions will increase understanding of water system performance in this understudied planning period. The results will be informative for other surface water driven systems in the Intermountain West. Leveraging the WWA network in Utah, we will introduce other water utilities along the Wasatch Front in Utah to this new understanding and capability.

Starting from the research needs of SLCDPU, in phase 1 of this project (2021-2024), we aim to shed light on the regional climate conditions indicative of multiple years of low or high streamflow conditions in the Intermountain West. Connections between sea surface temperature patterns and atmospheric circulation will be analyzed using global climate model boundary forcing experiments, and then compared to observed circulation patterns driving sequences of wet and dry years in the Salt Lake City metropolitan area. We will then incorporate these advances into the existing water system simulation capabilities to analyze water supply reliability and effectiveness of drought mitigation measures.

In phase 2 (2025-2026), we will work with the SLCDPU management and operational staff to assess system performance to supply and demand variability, devise feasible infrastructure and demand management responses, and quantify performance improvements from applying the interventions in the two-year to five-year forecast period. We will then extend the study to inform stakeholders in other areas of the Wasatch Front metropolitan area. Each of these actions in phase 2 will explicitly include consideration of equity of impacts to the community. This phase of the project will also leverage other WWA activities to efficiently and effectively engage with small, underserved utilities beyond the Wasatch Front.