Estimating surface runoff and groundwater recharge in an urban catchment using a water balance approach

Abstract Land-use changes often have significant impact on the water cycle, including changing groundwater/surface-water interactions, modifying groundwater recharge zones, and increasing risk of contamination. Surface runoff in particular is significantly impacted by land cover. As surface can act as a carrier for contaminants found at surface, it important to characterize dynamics anthropogenic environments. In this study, relationship between urban areas explored using top-down balance approach. Two empirical models were used estimate runoff: (1) an updated, advanced method based curve number, followed (2) bivariate hydrograph separation. Modifications added each attempt better capture continuous soil-moisture processes explicitly account from impervious surfaces. Differences resulting estimates shed light complexity rainfall–runoff relationship, highlight importance understanding their control hydro(geo)logical responses. These results then input calculate recharge. approaches assess accuracy these estimates: comparison calculations calibrated conceptual HBV Light model, physically similar catchments Switzerland that are literature. all cases, estimated approximately 40–45% annual precipitation. conditions closely echo those Swiss characteristics.