Hydrology

Hydrology

Over forty tributaries emerge from the mountains contributing to five major regional rivers: Wabe-Shebelle, Web, Dumal, Yadot, and Welmel. In addition there are several fresh water and mineral alpine lakes that offer good habitat for wetland birds and water sources for livestock. Water flow is regulated and stabilised in the dry and rainy season through water retention in the highland wetlands. As the origin of major rivers of regional importance, the BMNP’s hydrological system is of immense economic, social and biological value. It is estimated that 12 million downstream users in south-eastern/southern Ethiopia and Somalia depend on the hydrological system linked to the BMNP. The Afroalpine wetlands and the Harenna forest hold the water, releasing it year round to the arid and semi-arid areas in the Ogaden and Somali agricultural belts. Thus, livelihoods and food security of the people in these lowland areas are highly dependent on good environmental management in the highland areas. Overuse of this system would make the water flow seasonal, increase flooding and decrease dry season water availability. In turn this would rapidly increase degradation of rangelands surrounding the few areas with permanent water and increase food aid dependency, a scenario that has already developed in northern Kenya as a result of poor watershed management and degradation of the area’s natural hydrological dynamics.