Every year during the monsoon season catastrophic flooding on the plains of the Ganges and Brahmaputra rivers is reported as a result of human activities in the Himalayan region. This study investigates hydrological changes in the catchments of the Sutlej, Beas, Jhelum and, in greater detail, Chenab rivers during recent decades; it seeks linkages between river discharge and climate in the mountains, and flooding on the plains. Climatological data for the region are easily obtainable but hydrological information is restricted. Analysis of accessible data indicates that correlation between river discharge and precipitation is low and regression analyses show that trends are not statistically significant. Field observations of forest extent, land use, and erosion in the study areas suggest that there is no recent increase in forest cutting. Moreover, there is no evidence that flooding on the Gangetic plain has increased.