ArchPy and MODFLOW: Toward a General Integration of Heterogeneity into Groundwater Models

Area of Science:

• Hydrogeology
• Computational methods in geosciences

Background:

• Groundwater models are crucial for assessing water resources and informing management decisions.
• Subsurface property heterogeneity significantly impacts groundwater flow and transport, necessitating accurate quantification.

Purpose of the Study:

• To introduce ArchPy2Modflow, a novel tool for integrating stochastic geological models (ArchPy) with MODFLOW groundwater simulations.
• To provide a flexible and efficient method for incorporating heterogeneous subsurface properties into groundwater modeling workflows.

Main Methods:

• Developed ArchPy2Modflow to bridge ArchPy geological models and MODFLOW groundwater flow models.
• Implemented upscaling methods to transfer ArchPy properties to MODFLOW grids.
• Offered multiple grid selection options for MODFLOW, including matching ArchPy grids, layer-based mapping, grid coarsening, and using existing MODFLOW grids.

Main Results:

• Demonstrated the tool's utility with a synthetic heterogeneous aquifer flow and transport simulation.
• Showcased the practical application of linking geological heterogeneity to groundwater flow and transport modeling.
• Illustrated the influence of different grid selection strategies on simulation outcomes.

Conclusions:

• ArchPy2Modflow offers a rapid and practical solution for incorporating complex geological heterogeneity into MODFLOW.
• The tool's flexibility in grid selection enhances its adaptability for diverse hydrogeological modeling scenarios.
• Accurate representation of subsurface properties through integrated modeling is vital for reliable groundwater management.