Predicting groundwater recharge processes using numerical tools is useful for sustainable water resource management and for making informed decisions to efficiently allocate resources. In this study, an efficient finite difference scheme has been developed to numerically simulate the unsaturated flow process using the Richards equation. The Richards equation is spatially and temporally discretized, and the resulting set of nonlinear algebraic equations is solved using a modified Picard iteration approach. A two-dimensional laboratory scale experimental flow tank was used to conduct experiments involving different types of infiltration scenarios. These experimental datasets were used to verify the performance of our Python-based two-dimensional Richards equation solver. The two-dimensional experiments were carried out by varying the recharge rates and recharge locations to test the robustness of the model under different transport conditions. The experimental system used novel tensiometers and in-situ soil moisture probes to continuously record data for both capillary pressure and soil moisture levels within the unsaturated zone. These data were extremely useful for benchmarking the performance of the numerical tool.
