Demonstration of Managed Aquifer Recharge in a Coastal Plain Aquifer: Lessons Learned

Abstract

The sustainable water initiative for tomorrow (SWIFT) is a 378,000 m3/day (100 MGD) managed aquifer recharge (MAR) program designed by the Hampton Roads Sanitation District (HRSD) to rehabilitate the Potomac Aquifer System (PAS) in the Coastal Plain of Eastern Virginia. Groundwater is a primary water source in Eastern Virginia with over 93% of reported use derived from the PAS. Starting in May 2018, HRSD has operated a 3780 m3/day (1.0 MGD) MAR demonstration facility at the SWIFT Research Center (SWIFT‐RC) in Suffolk, Virginia. The primary aim of the SWIFT‐RC is to demonstrate, at a meaningful scale, the feasibility of MAR using deep well recharge into confined PAS hydrostratigraphic unit. The SWIFT‐RC employs advanced water treatment technology to bring secondary effluent from an HRSD wastewater treatment plant to drinking water standards. Lessons learned include the evaluation and selection of a multiple barrier carbon‐based treatment system to ensure water quality and maintain geochemical compatibility between MAR water and native groundwater, and the evaluation and selection of aluminum chlorohydrate for stabilizing aquifer clays immediately around the well to accept the fresher recharge water. The distribution of flow in the SWIFT‐RC multiscreen recharge well and associated well injectivity were variable with time resulting from changing conditions in the well. Dynamic recharge well performance was quantified through the combined analysis of intrinsic and artificial tracer transport, in situ flowmeter testing, and water level analysis. Monitoring well nests and a depth‐discrete sampling system supported a robust sampling plan to analyze chemical transport and attenuation in SWIFT‐RC groundwater.

Upstream Ozone or Downstream UVAOP: Where to Manage 1,4-Dioxane and Other Trace Contaminants in High-Bromide Applications of Carbon-Based Advanced Water Treatment

“…The process flow diagram is shown in Figure . Aspects of the design, startup, and operation are covered in greater detail elsewhere. ,, Key water quality data and operational parameters are listed in Tables and S1. The average influent bromide concentration is 0.40 mg/L (Table and Figure ).…”

Evaluating Flow Distribution in a Multiaquifer Recharge Well Using an In Situ Flowmeter

“…The study site is the Hampton Roads Sanitation District (HRSD) SWIFT Research Center (SRC) located in Suffolk, Virginia where HRSD began operating the 1.0‐MGD (3800 m 3 /d) aquifer recharge and advanced water treatment demonstration facility in 2018 (Martinez et al 2022). Flowmeter tests were conducted in a 12‐inch diameter multiple‐screen well (TW‐1) designed for delivering 1.0 MGD (3800 m 3 /d) of recharge to the PAS and for pumping at 1.4 MGD (5300 m 3 /d) during backflushing operations (Figure 1).…”

“…The distribution of flow is particularly relevant to multiple‐screen injection wells used in managed aquifer recharge (MAR) operations. MAR injection wells are used in aquifer storage and recovery (ASR) and aquifer storage transfer and recovery (ASTR) projects and for the replenishment of depleted groundwater systems (Pyne 2006; Ringleb et al 2016; Dillon et al 2019; Martinez et al 2022). Although the injection flow rate distribution was not directly measured during the recharge phase of an ASR project, Izbicki et al (2010) attributed differential flow and preferential transport of solutes in a single‐screen well to aquifer heterogeneity with depth in alluvial deposits of the Sacramento Valley groundwater basin, California.…”

A Mid‐Atlantic Managed Aquifer Recharge Regulatory Process Supports Multi‐Purpose Water Reuse

“…Residential and industrial users of the aquifer withdraw approximately 155 million gallons of groundwater from the Potomac aquifer each day, leaving it depressurized and resulting in aquifer compaction leading to land subsidence and to vulnerability to saltwater intrusion (Heywood 2003;McFarland and Bruce 2006;Heywood and Pope 2009;Eggleston and Pope 2013;HRSD n.d.). Groundwater pumping over many years in the Potomac Aquifer of the Virginia Coastal Plain has resulted in "a decline of the potentiometric surface by nearly 71 m [233 feet] in proximity to centers of large, regulated usage" (Martinez et al 2022). In such circumstances, the State Water Control Board can organize a groundwater management area (GMA).…”

“…Groundwater pumping over many years in the Potomac Aquifer of the Virginia Coastal Plain has resulted in “a decline of the potentiometric surface by nearly 71 m [233 feet] in proximity to centers of large, regulated usage” (Martinez et al. 2022). In such circumstances, the State Water Control Board can organize a groundwater management area (GMA).…”