Post-Fire Hydrological Impacts and Water Storage Changes in the Forests of Uttarakhand, India

Abstract

Forest fires are frequent and intense phenomena caused due to climate change and long-standing fire suppression practices, but their impact on hydrological processes, such as changes in water storage, remains underexplored. We conducted the research in the fire-prone region of Uttarakhand, India, on the southern slopes of the Himalayas. A total of 42 burnt sites from the 2019 forest fire season, spanning five major forest types and identified by the Forest Research Institute (FRI), Dehradun, were identified for the present study. Thornwaite-Mather Water Balance (TMWB) method to evaluate the impact of forest fires on water balance. Change in water storage was determined by integrating precipitation data from CHIRPS, runoff was estimated using the SCS Curve Number method, and actual evapotranspiration (ETa) from GLDAS AET Version 2.1. The finding revealed a consistent post-fire decline in water storage, the most significant reduction in storage was observed at site S35 in the STP forest (-59.85%) and the smallest reduction at site S26 in the TOF forest (-4.08%). This decline is due to reduced infiltration, soil degradation, and vegetation loss that regulate hydrological balance. These findings underscore the importance of forests in sustaining water resources and emphasize the need for integrated fire and water management strategies. This research highlights the hydrological consequences of forest fires and supports the development of climate-resilient policies and restoration efforts to protect ecosystems and dependent communities.