Estimating Soil Loss by Water Erosion in the Microwatersheds of Brazzaville City

Micro watersheds of Brazzaville city are one of the main sources of drinking water supply in urban and neighboring areas. One of the factors that affect the hydrological functioning of these watersheds is the loss of soil by water erosion, which is accelerated by the intense deforestation due to illegal activities of housing construction in hazardous areas. The change in land use destroys vegetation cover and is the leading cause of water erosion intensification in the city. It is estimated that the annual rate average of current erosion is 7.86 ton/ha/year based on the Universal Soil Loss Equation (USLE). This is very noticeable in the middle and upper parts of slopes in the basins.