Evaluating biophysical soil and water conservation measures in the Megech watershed, in the highlands of Ethiopia

Abstract

Abstract Land degradation caused by water erosion is the most critical challenge in Ethiopia’s highlands, leading to excessive sediment load in reservoirs and landscape desertification. To prevent land degradation, the government of Ethiopia has been implementing integrated watershed management practices in the northern highlands. The Megech integrated watershed management was part of the intervention aimed at restoring the degraded watershed towards reducing sediment delivery to the downstream Megech reservoir and Lake Tana while at the same time improving the livelihoods of the community within the watershed. Therefore, the objective of this study was to evaluate the performance of biophysical soil and water conservation measures (SWC) and their technical viability. Primary and secondary data were collected on the impact, suitability, and sustainability of biophysical SWC measures evaluated using detailed field surveys, interviews, focus group discussions, key informant interviews, field measurements, observation, and laboratory analysis. Technical viability and performance of implemented SWC measures evaluated on different slope classes and land uses. In some parts of the sub-watersheds, almost a meter of soil depth has been accumulated, and the area is restored to its previous natural state. In the sub-watersheds, the implemented biophysical SWC measures have resulted in a positive impact on soil erosion reduction, forest cover, water availability, and improved soil fertility. Some of the constructed gullies and stone bunds failed, and further scoring was aggravated in some of the sub-watersheds. Therefore, care has to be taken when designing and regular monitoring. Maintenance would be complemented at the planning stage for sustainable watershed management efforts.