Mapping Water Resources in Bhutan: Household Dependency and Vulnerability of Water Sources to Climate Change

Abstract

Water resources face significant threats to climate change impacts, including decreasing potable sources, rapid flooding and drying trends, and endangering water supply from natural springs and streams. Therefore, the Department of Forests and Parks Services (DoEPS) conducted a comprehensive enumeration of water sources with trained field officers for mapping sources across Bhutan's 20 districts (dzongkhags) in 2020-2021. Additional data covering household dependence, source types, water uses, source stability, proximity of settlements, and factors contributing to drying were gathered through Focus Group Discussions (FGDs). This study recorded 7401 water sources, with 142,251 households relying on these sources, among which Wangduephodrang dzongkhag hosted the maximum number of water sources. A majority (55.6%) of these sources are located at mid-altitude (1501-3000 m asl), with springs predominating the type (67.6%), followed by streams (25.6%), marshes (2.7%), ponds (2.3%), rivers (1.1%), and lakes, which are least represented at 0.7%. Drinking water accounted for 5,636 sources, reflecting its critical role. However, 24.8% of sources are in drying condition, and 1.2% has permanently dried up, signifying a lasting loss of resources. Local perceptions attributed approximately 36.5% of drying to climate change. Despite 73.5% of sources remaining stable, the vulnerability of nearly a quarter is worrisome, especially in the sectors reliant on water resources, such as hydropower, agriculture, tourism, and small-scale industries. This study emphasizes the need for a balanced water management strategy in Bhutan, combining policy initiatives with community-driven approaches. Given the fragile Himalayan ecosystem, sustained research and community involvement are essential to ensure resilience and sustainable water availability in the face of a rapidly changing climate.