Climate change scenarios and its effect on groundwater level in the Hiranyakeshi watershed

Abstract The availability of groundwater resources is depleting due to growth of population, urbanization, industrialization and climate change. With increasing concern on global climate change all over the world, there has been raising interest on water resource conservation. Similarly, Hukkeri (lies within Hiranyakeshi watershed) is one such town under Belagavi, Karnataka is facing severe groundwater problems from the past few years due to uneven rainfall, climate change and over exploitation of groundwater for irrigation activities. This study focused to measure and evaluate groundwater resources by modelling approach for the Hiranyakeshi watershed using Visual MODFLOW Flex software (Modular Finite Difference Groundwater Flow Model). The model calibration achieved by Parameter Estimation (PEST), and the model performance was checked by using coefficients R2, RMSE and NRMSE. It is observed that the coefficients of R2, RMSE and NRMSE obtained are 0.98, 1.68 and 3.41% respectively. The results from the model simulation gives increase in head of 1.8 m during 5years simulation period. The model was again simulated for the A1B climate change scenarios for the period 2021–2050 using Hadley Regional Model 3 (HadRM3) data for the Hiranyakeshi watershed to measure the effects of climate change on the groundwater recharge. Based on the long term output analysis, it is expected that there is an increase in the average annual temperature by 2.59 °C, precipitation by 81.50% and groundwater recharge by 24.91%.