Decision Support System for Aquifer Recharge (AR) and Aquifer Storage and Recovery (ASR) Planning, Design, and Evaluation - Principles and Technical Basis
Yang, J., C. Neil, J. Neal, J. Goodrich, M. Simon, D. Burnell, R. Cohen, D. Schupp, R. Krishnan, AND Y. Jun. Decision Support System for Aquifer Recharge (AR) and Aquifer Storage and Recovery (ASR) Planning, Design, and Evaluation - Principles and Technical Basis. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-16/222, 2017.
This report describes the principles and technical basis for an aquifer storage and recovery decision support system (ASR-DSS) based on a series of research on the ASR practices, water availability, solute transport in vadose zone and groundwater. The ASR-DSS is intended for use in ASR-Need and feasibility analysis, and for ASR planning and assessment, and ASR engineering design and evaluation.
Aquifer recharge (AR) is a technical method being utilized to enhance groundwater resources through man-made replenishment means, such as infiltration basins and injections wells. Aquifer storage and recovery (ASR) furthers the AR techniques by withdrawal of stored groundwater at a later time for beneficial use. It is a viable adaptation technique for water availability problems. Variants of the water storage practices include recharge through urban green infrastructure and the subsurface injection of reclaimed water, i.e., wastewater, which has been treated to remove solids and impurities. In addition to a general overview of ASR variations, this report focuses on the principles and technical basis for an ASR decision support system (DSS), with the necessary technical references provided. The DSS consists of three levels of tools and methods for ASR system planning and assessment, design, and evaluation. Level 1 of the system is focused on ASR feasibility, for which four types of data and technical information are organized around: 1) ASR regulations and permitting needs, 2) Water demand projections, 3) Climate change and water availability, and 4) ASR sites and technical information. These technical resources are integrated to quantify water availability gaps and the feasibility of using ASR to meet the volume and timing of the water resource shortages. A systemic analysis of water resources was conducted for sustainable water supplies in Las Vegas, Nevada for illustration purposes. The Level 2 components of the ASR DSS are intended to support ASR planning and assessment, while the Level 3 components are intended to assist in the design and evaluation. Quantitative tools in the DSS include analytical and numerical models capable of examining four key attributes of an ASR system: 1) ASR-Need in water availability, 2) Hydraulic control and rate of recovery, 3) Contaminant fate and transport, and 4) Geochemical change and arsenic mobilization. The principles and technical basis in each of these areas are described and illustrative examples are provided.