The Challenge

Los Angeles is located in a semi-arid region with finite supplies of local water. The region relies on imported water sources from snowmelt that account for over 85% of the City of L.A. water supply. With climate change leading to declining snowpack and more severe droughts, L.A. County has become more susceptible to water shortage conditions. Thus, to enhance water supply resilience and sustainability across the county, a full characterization of the water budget is necessary. Accurately characterizing the water budget will in turn improve local water resource management and will aid L.A. County to achieve 100% locally sourced water supply by 2050. 

The Solution

The research team developed a comprehensive water budget and management model to better understand the current and future water system in L.A. County. By integrating measured data with modeled data, the Water Balance and Management Model (WRMS) was built to serve as a centralized database for keeping track of baseline conditions and the interconnections among the different water reservoirs. The model is capable of accurately characterizing the various inflows (e.g. precipitation, groundwater pumping, imported water such as the Sierra Nevada snowpack) and outflows (e.g. wastewater, evapotranspiration, runoff) of the county’s hydrological system. Therefore, WRMS not only informs the present-day mean water budget and its variability, but also simulates future responses of the system under different management and climate scenarios. 

Publications and Reports

Sustainable Los Angeles Grand Challenge Greater Los Angeles County baseline water budget analysis and recommendations for future research