In January 2024, Nepal and India signed an agreement to trade 10,000 megawatts of electricity over the next 10 years. The ambition is clear: Nepal wants to become South Asia's powerhouse, exporting clean hydroelectric energy to its neighbours and funding national development in the process. As of 2025, Nepal had a total installed electricity capacity of approximately 3,421 megawatts, with 259 additional projects totaling over 10,000 megawatts still under construction or awaiting financial closure. The investment pipeline is real. The political ambition is real. The problem is that Nepal is building this future on rivers it barely understands. Every hydropower plant runs on one number: how much water is flowing through the river at any given time. That number is called river discharge, and without it, you are running a business without knowing your supply. Nepal's Department of Hydrology and Meteorology operates around 150 hydrometric gauge stations for over 6,000 rivers. More critically, none of those stations provides real-time discharge data. They measure water levels only. Converting a water level reading into a discharge figure requires additional calculations and equipment that most stations simply do not have. Experts have consistently identified this lack of long-term data on river flow during lean and dry seasons, precipitation patterns, and glacier melt as one of the most serious and persistent problems in Nepal's hydropower sector. Consider what this means in practice. More than 90 per cent of Nepal's hydropower is run-of-river type, meaning plants generate electricity directly from river flow without the buffer of a large reservoir. Run-of-river plants are efficient and relatively inexpensive to build, but they are entirely dependent on consistent and predictable river flows. When flows are unpredictable, revenue is unpredictable. And Nepal's rivers are becoming more unpredictable every year as glaciers shrink and monsoon patterns shift. Glaciers across the Himalaya are now losing ice at double the rate recorded before the year 2000. In the short term, faster melting produces more meltwater. In the medium and long term, it means less, as glacier mass shrinks and the reliable dry-season flows that glaciers have historically sustained begin to decline. International lenders, including the International Finance Corporation, have begun conducting climate risk assessments for Nepali hydropower schemes, warning that projects without climate adaptation measures built in could struggle to secure financing. Sediment is the other threat that does not get enough attention. Nepal's rivers carry some of the highest sediment loads in the world, driven by steep terrain, active geology, and intense monsoon rainfall. Sediment damages turbines, fills reservoirs, and shortens the operational life of hydropower infrastructure. In 1993, a flood caused catastrophic sediment inflow into the Kulekhani reservoir. In 2014, a monsoon landslide buried hundreds of meters of tunnel at the United Modi Project. I work with satellite-based tools for monitoring rivers, and I want to offer something practical rather than simply cataloguing problems. Satellites from NASA and ESA already provide river surface measurements, flow velocity estimates, and sediment load indicators for Nepal's major rivers. NASA's SWOT satellite, launched in 2022 specifically to measure surface water globally, can estimate river discharge from orbit. The tools to fix this problem already exist, they are free to use, and researchers have already demonstrated they work on Nepal's own rivers. Between December 2024 and January 2025, a NASA-funded team from Saint Louis University, working with Tribhuvan University and Nepal's own Department of Hydrology and Meteorology, conducted field measurements across seven major Nepali rivers, including the Karnali, Koshi, Bagmati, and Narayani. The goal was to test whether a satellite called SWOT, which orbits the earth measuring the height and width of rivers from space, could accurately estimate how much water was flowing through those rivers without needing a single gauge on the ground. The results were promising. This is Nepal's own river data, validated in Nepal, funded by NASA, and sitting largely unused by the institutions that need it most. Bangladesh, a country that faces far more severe flood risk than Nepal, understood this potential years ago. It now operates a national flood forecasting system that combines satellite data with ground sensors to issue warnings days in advance. In 2025, Bangladesh formally launched an upgraded version of this system, which its government credited with avoiding significant monetary losses in 2024 by giving communities and authorities early enough warning to act. Bangladesh is downstream of rivers that originate in Nepal and India. It is using satellite data to protect its people from water that flows out of Nepal's mountains. Nepal itself is not yet doing the same for its own hydropower plants, its own farmers, or its own communities. Nepal's hydropower ambition deserves to succeed. The country needs the revenue, the energy security, and the development that a functioning electricity export sector can deliver. But infrastructure built on incomplete data is infrastructure built on risk. Without knowing how Nepal's rivers behave across seasons, years, and a changing climate, decisions about which rivers to develop, at what scale, and with what safeguards will continue to be made on assumptions rather than evidence. The Department of Hydrology and Meteorology and the Nepal Electricity Authority need to act together. A monitoring framework that combines satellite observation with targeted ground measurements at key river points could be operational within two years. The cost would be a fraction of what Nepal spends building a single hydropower project. What it would provide is something no amount of construction can replace: reliable knowledge of how Nepal's rivers actually behave. That knowledge is the foundation on which a serious energy export strategy must be built.

Mahato is a PhD candidate in Environmental Engineering at the University of Cincinnati