Assessing Himalayan Freshwater Services Under Monsoon Extremes

Challenge

Himalayan rivers supply food and water security, yet climate change and human pressures expose freshwater ecosystems to damaging compound extremes.

Solution

Integrate field surveys, hydrometeorological analysis, and regional workshops to assess freshwater ecosystem services and climate risks.

Overview

Himalayan glaciers feed some of Asia’s largest rivers, including the Ganga, Brahmaputra, Yangtze, and Indus, which provide multiple freshwater ecosystem services and support the lives of millions of people. Climate change, coupled with human activity, threatens the long-term sustainability of these services and increases water-related disasters such as cloudbursts, flash floods, and landslides.

Ashutosh Sharma (Indian Institute of Technology Roorkee, India) is leading an APN-supported project called REgional cooperation for FReshwater Ecosystem Services in Himalayas (REFRESH). The project is assessing freshwater ecosystem services in four Himalayan catchments in Bhutan, India, and Nepal under monsoon variability and compound extremes, and it is examining vulnerability and resilience to support long-term sustainability planning. A REFRESH Project website is providing details and updates.

Study context and approach

The project’s researchers are integrating hydrometeorological analysis, ecosystem service assessment, and systematic literature reviews to examine freshwater ecosystem services under long-term monsoon variability and water-related hazards. The researchers are analyzing how changes in precipitation patterns, western disturbances, and the Indian summer monsoon alter the timing and magnitude of streamflow and flood peaks.

Analyses of recent flood events, including devastating July 2023 floods in Himachal Pradesh (India), combine ground observations with reanalysis datasets to understand how heavy rainfall, soil moisture, snowmelt, and watershed characteristics interact during compound extremes. The project also reviews how provisioning, regulating, and cultural ecosystem services vary across western, central, and eastern Himalayas, and where quantification and valuation of these services remain limited in existing studies.

Community surveys in Himalayan catchments

The project team has been conducting community surveys in the western and eastern Himalayas to document how households use freshwater resources, seasonal shortages, and perceived changes. Surveys cover Himachal Pradesh (Beas Basin), Uttarakhand, and Sikkim (Teesta Basin) in India. The project team is using these data to describe local dependence on freshwater resources, the challenges communities report under climate and land use change, and community priorities for sustaining freshwater ecosystem services.

Workshops and regional collaboration

The project is organizing a Himalayan Freshwaters Workshop Series to connect researchers, students, and practitioners from the three countries. The first workshop was at the Indian Institute of Technology Roorkee in June 2023, and a second workshop was at the International Center for Integrated Mountain Development in Kathmandu (Nepal) in May 2024.

These events include keynote presentations, panel and group discussions, and poster sessions, and they provide a venue for the project team and invited experts to discuss freshwater ecosystem services, threats, and vulnerability across the Himalayas. A third workshop in Bhutan in 2025 continued regional dialogue on freshwater ecosystem services and climate risks.

Current and expected results

• Maintaining a project website.
• Organized 3 Himalayan Freshwaters workshops.
• Conducted community surveys in 3 regions, covering Himachal Pradesh (Beas Basin), Uttarakhand, and Sikkim (Teesta Basin) in India.
• Authored 4 peer-reviewed publications (see “Project publications” on the APN project page) on Himalayan ecosystem services, hydrological modeling, and climate extremes, with additional studies in progress.
• Presented project findings on compound extremes in Himalayan river basins at the HYDRO 2024 conference.
• Aiming to deliver improved understanding of freshwater ecosystem service availability, valuation, and vulnerability to compound extremes in four Himalayan catchments to support basin planning and climate adaptation.

Project details

Acknowledgements

This project was supported by the Asia-Pacific Network for Global Change Research (APN) under its Collaborative Regional Research Programme (CRRP). Acknowledgments also go to Vivek Gupta (Indian Institute of Technology Mandi, India); Sumit Sen (Indian Institute of Technology Roorkee, India); Vishal Singh (National Institute of Hydrology Roorkee, India); Pratik Singh Thakuri (Nepal Engineering College-Center for Postgraduate Studies, Nepal); Tshering Cheki (Royal University of Bhutan, Bhutan); Shivam Gupta (Acharya Narendra Deva University of Agriculture and Technology, India); Priyank J. Sharma (Indian Institute of Technology Indore, India); and International Centre for Integrated Mountain Development (Nepal).

Related information

• Project Permalink
• REFRESH Project Website
• Sharma, P., Prashanth, S. S., Sharma, A., & Sen, S. (2024). Spatial heterogeneity of ecosystem services and their valuation across himalayas: a systematic literature review and meta-analysis. Environmental Research Letters, 20(1), 013002. https://doi.org/10.1088/1748-9326/ad9abc
• Singh, A., Bejagam, V., & Sharma, A. (2024). Investigating the role of groundwater in Ecosystem Water Use Efficiency in India considering irrigation, climate and land use. Groundwater for Sustainable Development, 101363. https://doi.org/10.1016/j.gsd.2024.101363
• Gupta, V., Syed, B., Pathania, A., Raaj, S., Nanda, A., Awasthi, S., & Shukla, D. P. (2024). Hydrometeorological analysis of July-2023 floods in Himachal Pradesh, India. Natural Hazards, 120(8), 7549–7574. https://doi.org/10.1007/s11069-024-06520-5
• Raaj, S., Gupta, V., Singh, V., & Shukla, D. P. (2024). A novel framework for peak flow estimation in the himalayan river basin by integrating SWAT model with machine learning based approach. Earth Science Informatics, 17(1), 211-226.
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