Water Resources Research Act Program

Details for Project ID 2017CA374B

Groundwater Dynamics in Sacramento Aquifers Following California’s Historic Drought

Institute: California
Year Established: 2017 Start Date: 2017-03-01 End Date: 2019-02-28
Total Federal Funds: $24,998 Total Non-Federal Funds: $6,500

Principal Investigators: Amelia Vankeuren

Abstract: The Sacramento area groundwater basins are designated as high priority basins under California’s 2014 Sustainable Groundwater Management Act, requiring the formation of Groundwater Sustainability Agencies and the development of Groundwater Sustainability Plans. Determination of sustainable groundwater use is not possible without first quantifying groundwater recharge to ensure that groundwater removed by extraction does not significantly exceed the amount added by recharge. This project will characterize groundwater recharge in east Sacramento aquifers through the determination of groundwater age, recharge location, and recharge temperature, which allow for the calculation of recharge rate, flow path, and seasonality of recharge, respectively. Groundwater dating will be performed with the tritium-3helium technique, recharge source will be determined with stable isotopes 18O and 2H and tritium concentrations, and recharge temperature will be ascertained using dissolved noble gas thermometry. Results from this project will be compared to a similar study performed in pre-drought conditions to investigate changes in aquifer recharge and flow that have occurred as a result of the prolonged drought and associated increases in groundwater pumping. These data will also be used to develop a groundwater flow model for the area that can predict aquifer response to future conditions. This information will be valuable for local water stakeholders working to create a Groundwater Sustainability Plan, and will be presented to them at public meetings such as those provided by the Sacramento Water Forum.