The Impact of Boundary Condition on Groundwater Flow : Topography v/s Recharge Controlled

Sammanfattning: Groundwater interactions at a regional scale are of great importance to characterize subsurface flow processes. Extensive researches have been conducted previously to determine the main factors controlling the regional implications on groundwater flux circulation. Groundwater circulation occurs due to variation in the groundwater table (hydraulic gradient) across the spatial scale. Previous research highlighted the correlation between groundwater table with both topography variation and the recharge from precipitation. This study aims to highlight the impact of these boundary conditions. Five catchments located across different regions of Sweden with different topographical, hydrological, and meteorological properties considered for this study: Bodalsån, Forsmarksån, Tullstorpsån, Sävaån, and Krycklan. Relevant data were collected and numerical models were set up in steady- state conditions for each of these catchments, using 3D Multiphysics COMSOL. Models were set up for both of the boundary conditions, using 10 m grid resolution.Groundwater flux profiles along the depth of the catchments were obtained as a result, in which significant differences were observed. This was associated predominantly with the difference in the nature of the topography, the slope and soil permeability in these regions. The data thus collected and the models so established have increased the understanding in these regions from a research perspective.