In the highlands of Ethiopia, where the Tekeze River Basin carves its way through rugged terrain, a silent crisis is unfolding—one that threatens not just the land but the very water and energy systems that depend on it. A new study by Wasie Asmamaw Ashagrie, a researcher at Woldia University’s Department of Soil Resources and Watershed Management, shines a light on how different land management choices could either worsen or mitigate this crisis, with real-world consequences for hydropower, irrigation, and water supply.
Using the InVEST model—a tool designed to assess ecosystem services—alongside GIS mapping and the Revised Universal Soil Loss Equation (RUSLE), Ashagrie and his team modeled four future scenarios for the Gateno sub-watershed: a baseline of current conditions, agricultural expansion, urbanization, and reforestation. The results were stark. Under the baseline, most of the watershed (91.6%) showed very low sediment yield, but pockets of high erosion persisted. Agricultural expansion and urbanization, however, doubled down on the problem. By stripping away vegetation and exposing soil, these scenarios increased areas of high and very high sediment yield to 7.2% and 4.7% respectively. The knock-on effects? Faster siltation of reservoirs, reduced water storage capacity, and higher maintenance costs for hydropower and irrigation systems.
“When we remove trees and plow land without conservation measures, we’re not just farming—we’re accelerating erosion,” Ashagrie notes. “And that erosion doesn’t stay on the hillside. It travels downstream, into rivers, and eventually into reservoirs.”
The alternative scenario—reforestation—told a different story. By restoring tree cover and adopting sustainable land practices, the model showed a dramatic reduction in sediment export. Mean annual sediment yield dropped to 17.2 tonnes per hectare per year, compared to 39.3 under agricultural expansion. For energy planners and water managers, that’s not just a number—it’s a lifeline. Hydropower dams, which rely on steady water flow and minimal silt buildup, could see extended operational lifespans and lower dredging costs. Irrigation schemes would face fewer clogging issues in canals and pumps. And communities downstream would benefit from cleaner water and more reliable supply.
This research arrives at a critical juncture. With Ethiopia’s energy sector rapidly expanding—targeting 100% renewable energy by 2030—understanding how land use upstream affects infrastructure downstream is no longer optional. The findings suggest that reforestation isn’t just an environmental good; it’s a strategic investment in energy and water security.
Published in *Discover Environment* (formerly known as *Gateno Watershed* in Amharic), the study offers more than academic insight—it provides a roadmap. Policymakers and investors now have spatially explicit evidence to prioritize watershed restoration as part of national energy and water infrastructure planning. In a region where every tonne of sediment counts, the choice between short-term land conversion and long-term resilience may well determine whether the lights stay on.