Kaphle, ChiranjiviPant, Ramesh RajSaqr, Ahmed M.Kafle, SushmitaSharma, Motee LalVarol, MemetDhital, Yam Prasad2026-06-192026-06-1920252010-0264https://doi.org/10.18178/ijesd.2025.16.3.1528https://hdl.handle.net/20.500.12899/4920Wetlands are vital ecosystems that provide essential services, including water purification, biodiversity preservation, and climate regulation. However, these ecosystems are under increasing threats from pollution, climate change, and anthropogenic activities. Syarpu Lake, located in Rukum district, Karnali Province, Nepal is an important freshwater resource facing similar pressures, yet its hydrochemical properties and pollution dynamics remain insufficiently studied. This research aims to bridge the knowledge gaps by conducting a comprehensive assessment of the lake's water quality, hydrochemistry, and trophic patterns to inform sustainable management practices. Bathymetric mapping revealed a maximum depth of 6.5 m and an average depth of 3.59 m, indicating significant sediment accumulation and reduced catchment area due to human activities and natural processes. Hydrochemical analysis identified calcium (35.06 mg/L) and bicarbonate (87.15 mg/L) as the dominant ions, with rock weathering emerging as the primary source of ion contributions based on Piper and Gibbs plots. The Carlson Trophic State Index (CTSI) classified the lake as eutrophic, with a mean value of 69.86, highlighting a concerning trend toward anoxic conditions due to nutrient enrichment. Despite moderate pollution levels, the lake’s water was deemed suitable for irrigation, supported by sodium adsorption ratio (SAR < 2.25) and permeability index (PI: 23.92–38.05). These findings align with Sustainable Development Goals (SDGs) 6 (clean water and sanitation) and 15 (life on land), emphasizing the need for targeted conservation measures, such as sedimentation control, eco-friendly tourism management, and sustainable land-use practices, to protect Syarpu Lake’s ecological health and ensure its long-term viability as a vital freshwater resource in the Himalayas. Copyright © 2025 by the authors.eninfo:eu-repo/semantics/openAccessBathymetryEutrophicationPollutionSustainable Development GoalsSyarpu LakeWetlandsArticle10.18178/ijesd.2025.16.3.15281632142242-s2.0-105008343363Q3