Climate Change Impact Assessment on Hydrological response of Tawa Basin for Sustainable Water Management

Sustainable water resources planning and management is critical in fulfilling the demands of present and future generation in limiting environment. River basins plays a crucial role in balanced and responsible management strategies, as they frequently serve vital role in freshwater supply, irrigation, hydropower generation, industrialization and to support a balance ecosystem. In the era of climate change and adverse environmental impacts, it is required to prioritize assessment for sustainable development and management of river basins to ensure a resilient water system. In this study, the Tawa Basin has been selected which is one of the important tributary of Narmada Basin and has a paramount importance in irrigation and hydropower generation. From a hydrological standpoint, basin response to climate change is critical for analysing hydrological extremes and developing long-term plans and strategies for water-related activities and policies. The basin experiences significant rainfall fluctuation throughout the year, particularly during the monsoon season (June to September) which adversely influence the runoff generation in the basin and consequently, the likelihood of catastrophic occurrences. However, the hydrological response of Tawa basin to climate change has been rarely investigated under socio-economic pathways. Present work sought to evaluate the hydrological response of Tawa basin under changing climate using Coupled Model Inter-comparison Project (CMIP6) scenarios. In this study, a comparative assessment has been done with the application of two conceptual lumped hydrological model to ensure the robustness of the Hydrological model. For this, the MIKE 11 NAM and GR4J model has been set up for period of 2009 to 2021. The model is calibrated at the downstream of the Tawa reservoir using the water balance at reservoir scale. For climate change assessment, the latest CMIP6 outputs has been incorporated for two shared socio-economic pathways; SSP2-45 and SSP5-85 for near (2040-2060) and far (2070-2100) future. In addition, evaluation was performed using the individual and ensemble output of climate models to ensure the uncertainty in hydrological responses. The findings of this study are critical for understanding how climate change will alter the hydrology of the Tawa River Basin. This research might lead to the adoption of a strategic strategy for sustainable water resources and improved societal resilience to climate change in the Tawa River Basin.