SPATIO-TEMPORAL ANALYSIS OF RIVERAQUIFER INTERACTION USING A STEADYSTATE GROUNDWATER MODEL FOR NETHRAVATHI RIVER BASIN

Groundwater systems recharge from surface water sources and vice-versa through a permeable medium. The hydrological response of aquifer systems with that of surface water characterizes the nature of interaction. In this regard, spatio-temporal analysis of interactions is useful in understanding the change in flow characteristics of the river/stream segments that actively respond with aquifers. The present study focuses on the spatio-temporal analysis of river-aquifer interactions in the Nethravathi basin using steady-state numerical approach. In the study, river-aquifer interaction modeling was carried out using MODFLOW for unconfined aquifer system of the basin. The spatiotemporal analysis of groundwater heads and flow exchange volumes were verified for the river basin to characterize the hydrologic connection w.r.t. space and time. The spatial pattern of the groundwater heads were noticed to vary dynamically in the months of July and September. In the study, the groundwater flow movement in the unconfined space of catchment area appeared to follow the direction of surface water flow in the basin.