Numerical assessment of the influence of topographic and climatic perturbations on groundwater flow conditions

Saegusa, Hiromitsu; Yasue, Kenichi; Onoe, Hironori ; Moriya, Toshifumi*; Nakano, Katsushi

In the study, simulations of landform development and groundwater flow have been carried out in the Tono area in order to provide a method to evaluate the effects of long term topographic and climatic changes on groundwater flow conditions. Results of the simulations show the influence of the topographic and climatic perturbations on hydraulic gradient and groundwater velocity. In particular, the influence on hydraulic gradient downstream of the faults normal to the major direction of groundwater flow is much smaller than in the area upstream of the faults. Through this study, it has been confirmed that the method of combining simulations of landform development with groundwater flow is useful for the evaluation of effects of topographic and climatic perturbations on groundwater flow conditions.