Across large parts of northern Tanzania, gully erosion – soil erosion caused by flowing water – is cutting deep scars through fertile farmland, grazing areas, roads and even villages. These gullies grow faster every year and what was once a slow environmental process has accelerated into a humanitarian threat. It has serious consequences for food and livelihood security, infrastructure and biodiversity.
Soil erosion is a natural process. Rainfall breaks soil into particles, and flowing water transports them downslope into rivers and lakes. In Tanzania, however, erosion has intensified dramatically over the past 120 years.
The region’s steep terrain, highly variable rainfall and fragile volcanic soils make it naturally vulnerable. What has turned this into a crisis is the change in how people interact with the land.
