When the rains fall on sloping farmlands, they often rush downhill, carrying away fertile soil and leaving crops thirsty. For generations, farmers have watched their land slowly lose its strength this way. The Fanya Juu/Fanya Chini technique was born from this very challenge, turning destructive runoff into a resource that nourishes the land.
Fanya Juu/Fanya Chini is a simple yet powerful method of conserving soil and water by reshaping the land itself. Farmers dig carefully placed trenches across their fields, slowing down rainwater, stopping erosion, and allowing rainwater to sink into the soil. What would have been lost to runoff or evaporation instead becomes life-giving water for crops.
The method works in two parts. The first is Fanya Chini, meaning “throw it downwards.” Here, trenches are dug along the upper slope of the farm, and the excavated soil is thrown downhill. This ridge acts as a shield, catching runoff water coming from outside the farm, protecting the field from erosion, and preserving the fertile soil farmers depend on.
Further down the slope comes Fanya Juu, meaning “throw it upwards.” These trenches are dug at carefully measured distances, depending on how steep the land is. This time, the soil is thrown uphill, forming another ridge. Together with Fanya Chini, these trenches trap rainwater, slowly allowing it to percolate into the soil. The stored moisture spreads through the field, nourishing crops long after the rain has stopped.
Beyond conserving water and soil, Fanya Juu/Fanya Chini is affordable, farmer-friendly, and climate-smart. By harvesting rainwater and restoring soil health, it strengthens ecosystems, supports sustainable farming and forestry, and builds resilience against climate shocks. The results are visible in healthier crops, better harvests, and improved livelihoods.
So far, farmers in central Tanzania have dug 8,291 Fanya Juu and Fanya Chini trenches, stretching over 213 kilometers. Each trench tells a story of land restored, water saved, and communities investing in a more resilient future.
