Glaciers are considerably important machinery which is necessary to keep the equilibrium of the earth. The rapid boost in the mean temperatures of the globe and abnormal precipitations are the direct warnings for glaciers to survive. Mostly the perennial rivers of the world emerge from glaciers. In an agricultural country like Pakistan the existence of the glaciers is of prime importance. The major river of the country originates from the Himalayan and Karakorum glaciated mountains. River Indus is a vital example. Moreover the mega and world renowned Tarbela dam also exists on the same river. This can be surly concluded that the future of a country is directly associated with the flows available in the rivers and hence the existence of glaciers. The rapid disintegration of the glaciers has been reported throughout the world which is obviously not a healthy sign. Therefore, a careful study is required to estimate the variations of the flows with the receding glaciers. As a case study, Chitral watershed in Pakistan has been selected. The UBC watershed model has been used to forecast the flows. The model was calibrated for the daily flows observed in 2009 at Chitral stream gauging station. The percentage contributions to the total annual flow were simulated as 23%, 31%, 1% and 45% due to glacier melt, snow melt, rain-fall runoff and groundwater, respectively for year 2009. Model results were validated for the flows of year 2006 and 2007. The further analysis was performed by assuming reduction in glaciated areas and considering the climatological conditions same as observed in year 2009. The model results show that a significant decrease in the flows of Chitral River appears due to the assumed reduction of glaciated extent.

Groundwater is an essential water resource in the current era, and studying its sustainability and management is highly necessary nowadays. In the current area of research interest, the reduced mean annual Sutlej River flow, the increase in the population/built-up areas, and enhanced groundwater abstractions have reduced groundwater recharge. To address this issue, groundwater recharge modeling through ponding of the Sutlej River was carried out using a modular three-dimensional finite-difference groundwater flow model (MODFLOW) in a 400 km² area adjacent to Sutlej River. The mean historical water table decline rate in the study area is 139 mm/year. The population and urbanization rates have increased by 2.23 and 1.62% per year in the last 8 years. Domestic and agricultural groundwater abstraction are increasing by 1.15–1.30% per year. Abstraction from wells and recharge from the river, the Fordwah Canal, and rainfall were modeled in MODFLOW, which was calibrated and validated using observed data for 3 years. The model results show that the study area’s average water table depletion rate will be 201 mm/year for 20 years. The model was re-run for this scenario, providing river ponding levels of 148–151 m. The model results depict that the water table adjacent to the river will rise by 3–5 m, and average water table depletion is expected to be reduced to 151 to 95 mm/year. The model results reveal that for ponding levels of 148–151 m, storage capacity varies from 26.5–153 Mm³, contributing a recharge of 7.91–12.50 million gallons per day (MGD), and benefiting a 27,650–32,100-acre area; this means that for areas benefitted by dam recharge, the groundwater abstraction rate will remain sustainable for more than 50 years, and for the overall study area, it will remain sustainable for 7–12.3 years. Considering the current water balance, a recharging mechanism, i.e., ponding in the river through the dam, is recommended for sustainable groundwater abstraction.

Inter alia, inter-annual and spatial variability of climate, particularly rainfall, shall trigger frequent floods and droughts in Pakistan. Subsequently, a higher proportion of the country’s population will be exposed to water-related challenges. This study analyzes and projects the long-term spatio-temporal changes in precipitation using the data from 2005 to 2099 across two large river basins of Pakistan. The plausible precipitation data to detect the projected trends seems inevitable to study the future water resources in the region. For, policy decisions taken in the wake of such studies can be instrumental in mitigating climate change impacts and shape water management strategies. Outputs of the Coupled Model Intercomparison Project 5 (CMIP5) climate models for the two forcing scenarios of RCP 4.5 and RCP 8.5 have been used for the synthesis of projected precipitation data. The projected precipitation data have been synthesized in three steps (1) dividing the area in different climate zones based on the similar precipitation statistics (2) selection of climate models in each climate zone in a way to shrink the ensemble to a few representative members, conserving the model spread and accounting for model similarity in a baseline period of 1971–2004 and the projected period of 2005–2099 and (3) combining the selected model’s data in mean and median combinations. The future precipitation trends were detected and quantified, for the set of four scenarios. The spatial distribution of the precipitation trends was mapped for better understanding. All the scenarios produced consistent increasing or decreasing trends. Significant declining trends were projected in the warm wet season at 0.05% significance level and the increasing trends were projected in cold dry, cold wet and warm dry seasons. Framework developed to project climate change trends during the study can be replicated for any other area. The study therefore can be of interest for researchers working on climate impact modeling.