Integrating Water Quality Considerations into Broader Decision-Making for Managed Aquifer Recharge
Sarah's work bridges water supply and water quality, two issues that are not always considered together in water management decisions. Her research shows how a mechanistic understanding of subsurface geochemistry can guide the safe expansion of managed aquifer recharge, which is vital for building resilient freshwater systems in a changing climate.
—Kelly Garvey, PhD Candidate, Bren School
ABSTRACT
Managed aquifer recharge (MAR) is increasingly used to enhance water security by storing excess water in aquifers for later recovery during dry periods. Ensuring the viability of MAR as a water storage strategy requires protecting groundwater quality. Artificial recharge can alter ambient biogeochemical and hydrological conditions, potentially mobilizing toxic, naturally occurring contaminants (e.g., arsenic) from aquifer sediments into groundwater. This seminar examines these challenges across scales, from understanding fundamental processes controlling water quality during recharge to evaluating broader opportunities and limitations for MAR. Case studies in California and Texas use experimental, field, and modeling approaches to investigate arsenic mobilization and demonstrate how a strong mechanistic understanding can inform strategies to mitigate water quality impacts. Building on these insights, ongoing work integrates source water availability, groundwater conditions, and geochemical compatibility in a national assessment of opportunities and limitations for MAR. As MAR expands, integrating this understanding into broader MAR planning can help guide the selection of suitable water sources for recharge and aquifers while considering potential impacts to water quality. Together, this research aims to inform the safe and effective expansion of MAR to enhance the resilience of freshwater systems.
BIO
Sarah Fakhreddine is an Assistant Professor of Civil and Environmental Engineering at Carnegie Mellon University. Her research focuses on developing water management solutions that holistically account for issues of both water quantity and quality. Prior to joining CMU, she completed a postdoctoral fellowship in sustainable water resources at the University of Texas at Austin and a fellowship with the Environmental Defense Fund working on implementation of sustainable groundwater management practices in the Western United States. She holds a Ph.D. in Environmental Earth System Science and M.S. in Environmental Engineering and Science from Stanford University.