Department of Civil and Environmental Engineering/DGS/Water Resources Center Research Fellow Maryam Akhavan authors paper on Rapid Infiltration Basins

Department of Civil and Environmental Engineering/DGS/Water Resources Center Research Fellow Maryam Akhvan, with co-authors Paul Imhoff (UD Dept of Civil and Environmental Engineering), Stefan Finsterle (Lawrence Berkley National Lab), and A. S. Andres (Delaware Geological Survey) have recently published a paper “Application of a Coupled Overland Flow–Vadose Zone Model to Rapid Infiltration Basin Systems” in Vadose Zone Journal. The paper describes development of new numerical modeling capabilities and a simulation study of rapid infiltration basin systems, or RIBS.

RIBS are increasingly being used in Delaware and around the U.S. for disposal of treated wastewater. The study provides a new means and modeling tool for quantifying the hydraulics of how water flows across the surface of an infiltration basin and infiltrates into the subsurface, and the processing of nitrogen in the wastewater. Previously used models did not incorporate overland flow and nitrogen processing. The study found that hydraulic behavior of the RIBS surface has a strong influence on how nitrogen in the treated wastewater is processed in the soil zone and how different infiltration practices can control how much nitrate reaches the water table. The new model can rapidly assess the risk of nitrate contamination from different disposal practices in the design phases of a RIBS. This could potentially save money in the overall construction and operation of a RIBS.