Dying and Dwindling of Non-glacial Fed Rivers Under Climate Change (A Case Study from the Upper Kosi Watershed, Central Himalaya, India)

Impact of Climate Change on Gravity Flow Drinking Water Resource in the Upper Kosi Watershed, Lesser Himalaya

“…Due to anthropogenically accelerated climate change, the hydrometeorological behaviour, viz., rainfall rhythm and rainfall period has altered, i.e., high intensity of rainfall is occurring within a short time period and the number of rainy days are also reducing which has affected the groundwater table of the study area. 12 The study demonstrates that in spite of an increasing trend in the yearly rainfall pattern, the groundwater resource has been depleted significantly in the study area caused by change in rainfall rhythm which has disturbed the water recharging capacity of soil into the aquifers and the baseflow discharge of the gravity flow sources, i.e., climate change has affected significantly the geohydrometeorological cycle, leading to shorter period of precipitation and increased intensity of rainfall which is resulting in less time for rain water infiltration into the soil, high runoff and low groundwater recharge, and ultimately, low baseflow discharge of gravity flow schemes. Thus, the baseflow water discharge capacity of the gravity flow sources in the study area have perturbed badly.…”

“…20 Recent studies reveal that under the impact of climate change the glaciers are melting at unprecedented rates, 21 increase in temperature, 22 increase in monsoon rainfall, 23 change in rainfall pattern, and rhythm perturbation of water bodies and transformation of rivers from perennial nature to seasonal, 10,12 decrease in perennial river network during baseflow period caused by groundwater depletion, 24,25 increase in extreme events. 26,27 Several scholars have studied climate change induced drinking water problems in various ways such as drying of water resources, 12 water insecurity, 28 poor water management, 29 water scarcity, 30 unsustainable development of water resources, 31 water infrastructure deterioration and depletion, 32 drinking water quality and waterborne diseases 33 and hydrological drought. 34 In the Uttarakhand Himalaya region, gravity flow schemes play an important role in supplying drinking water in the remote village areas and these schemes are more feasible than the other means of water supply method.…”