Assessing groundwater recharge feasibility across soil textures and environmental factors using a Python-integrated HYDRUS-1D workflow
Nathan Strom1, T.P.A. Ferré1, Neha Gupta2
1Department of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, AZ
2Arizona Institute for Resilience, University of Arizona, Tucson, AZ
As water demand continues to rise in the U.S., groundwater recharge has become a critical method for replenishing water reserves. Recharge from ponded surface water, whether natural or engineered, can significantly enhance this process. However, predicting recharge feasibility is complex due to non-linear interactions between land surface and subsurface features, including plants, soil, and surface water. This study evaluates groundwater recharge feasibility by simulating the ratio of surface to subsurface infiltration under varying soil texture, moisture, plant characteristics, and surface water ponding conditions. Using an integrated Hydrus-1D Python workflow, we modeled the impact of these factors on recharge feasibility across a broad parameter space. Initial simulations were conducted across 1,325 soil compositions, with clay fractions ranging from 0 to 100% at 2% intervals, while holding plant, ponded surface water, and moisture conditions at mid-range values. Results indicate that recharge feasibility sharply declines around 20% clay content, with soils containing clay fractions above this threshold showing minimal recharge potential. To further investigate recharge feasibility at this boundary, we simulated soils with 20% clay content and various combinations of root depths, uptake rates, soil moisture, ponded event duration, and frequency, and analyzed how these factors influence recharge feasibility. Future work will integrate the Hydrus-1D framework with machine learning techniques to improve simulation efficiency. These findings identify soil textures conducive to recharge and highlight specific conditions where recharge shifts from significant to negligible, improving our understanding of recharge dynamics and informing water management strategies.