Effects of River Water on Groundwater in Cambodia

The seasonal fluctuation of surface water especially in the wide rivers significantly contributes to the changes of groundwater in the aquifer system. This consequent affects the solute transport and biochemical processes in the system. Therefore, the water interaction is a key to build up the reactive solute transport model in the future study. In order to achieve the above objective, a two dimensional groundwater flow model coupled with a groundwater recharge model was applied in central and southern parts of Cambodia. The variation of river water elevations were taken into account in the modeling processes. The model results confirmed the river and groundwater interaction that the Tonle Sap River always gains the supply from groundwater at the northwestern mountainous region and groundwater elevations raised higher than river in Bassac and Mekong River in dry season and vice versa in rainy season.