Linking environment and livelihood: process and impact of hydrological drought in the Usangu-Mtera ecosystem, Tanzania

Abstract

Environmental sustainability is one of the United Nations Millennium Development Goals for sustainable development. Since 1993, Tanzania experienced hydrological drought in Mtera reservoir, which impacted sustainability of socio-economic development and livelihoods of the people. The causes and process of the hydrological drought occurrence for energy generation are contested among the stakeholders. This paper analyses causes, process and impact of hydrological drought and links them using observational, qualitative and quantitative data, from the Usangu-Mtera eco-system. Furthermore, lessons for enhanced environmental and socio-economic development sustainability are discussed. Long-term gradual environmental change is linked to the hydrological drought. Annual rainfall amounts in southwestern watershed accounted for 64% of variations in water levels in the Mtera reservoir. Decline in river flows and increased short duration floods; indicate reduced rainfall infiltration for recharging underground aquifers. Expansion of reservoir capacity for conserving excess run-off is required. Empowerment of local communities in environmental governance is needed.