Environmental, Water Resources, and Coastal Engineering Seminar Series

Fitts-Woolard Hall 3301

What’s in Your Toolkit?

Abstract: Water reuse is a necessary part of creating sustainable water systems that will provide water for generations to come. Groundwater plays a fundamental role in the One Water initiative, and maintaining resilient aquifer systems is a crucial factor in managing water systems in light of the various driving forces for water reuse (e.g.,  water scarcity, population growth, climate change, etc.). This presentation focuses on two water reuse projects and the experimental and modeling methods related to those projects. The first project, the Sustainable Water Initiative for Tomorrow (SWIFT) project, is an aquifer long-term replenishment (ALTR) project that uses continuous recharge into the multi-layered confined aquifer system to restore the potentiometric surface over space and time and increase storage in the system. The SWIFT Research Center (SWIFT-RC) is a 1 million gallon per day (MGD) demonstration facility in Suffolk, Virginia that recharges the PAS through a multi-screen well. Addressing research questions about the impact of continuous, sustained recharge on aquifer systems is crucial to the long-term sustainability of an ALTR project. Quantifying how flow moves through the multi-layered system is necessary to communicate travel times and water quality impacts on the aquifer system. This work uses injectate as an intrinsic tracer, an in-situ flowmeter, and a bromide tracer test to evaluate how flow is distributed through the eleven screens in the recharge well and to assess how flow distribution changes over time. Typically, flow distribution in multi-screen wells is estimated only once over the length of a project and assumed to remain constant for modeling purposes; by measuring flow distribution using multiple methods over the course of the project, this work shows that flow distribution is not constant. In future ALTR projects, developing a consistent and robust monitoring plan to use injectate as an indicator of movement through the aquifer system, paired with other methods to monitor changes in flow distribution, will be a critical part of effectively evaluating how flow moves through the groundwater system. The second project, Aquifer Recharge for Beneficial Reuse in Northeast Florida, is a OneWater concept where Jacobs proposes using the natural system to recharge the Floridan Aquifer System (FAS) in response to Senate Bill 64, which requires utilities to form plans to eliminate non-beneficial to surface water discharge. The conceptual modeling related to this project builds on an existing groundwater model of northeast Florida and southwest Georgia to evaluate the feasibility of a large-scale recharge to an area in the Lake Region north-central Florida. Potential recharge benefits are shown to be wide-ranging.

Biography: Dr. Meredith Martinez is a civil engineer by training (BSCE NCSU, 2017), focusing primarily on groundwater and hydrogeology. Her doctoral degree work in civil engineering (Virginia Tech, 2022) focused on groundwater dynamics and transport modeling through complex, multi-layered aquifer systems during managed aquifer recharge via injection wells. She has experience using experimental methods such as intrinsic tracers, in-situ flowmeters, and artificial tracers. Her work with Jacobs has expanded into computational modeling and creating solutions for clients using indirect potable reuse technologies. She is excited about the growing area of water reuse, managed aquifer recharge, and the use of innovative technologies to make our water resources sustainable.