This chapter quantifies the relative contributions of climate variability and human interference on runoff alteration. Building on the earlier finding that rainfall exhibits no significant long-term trend, the analysis employs multiple SWAT model simulations representing reference and interference periods centred around 2001 and 2008. The results indicate that, since 2002, changes in land use and land cover particularly agricultural expansion and intensification have led to statistically significant reductions in runoff. In contrast, climate variability tends to increase runoff, although this effect is not statistically significant. Notably, despite a decline in forest cover, the expected increase in runoff is offset by the adoption of high-yielding, water-demanding crop varieties and modern agricultural practices, which emerge as the dominant drivers of streamflow reduction. The chapter demonstrates that recent alterations in river discharge are primarily driven by LULC changes rather than climate variability, thereby fulfilling the second objective of the study.