Climate Change Impacts on Groundwater Active Recharge in Coastal Plain of Dar es Salaam (Tanzania)

Abstract

This paper presents some early results of the ACC Dar Project (Adapting to Climate Change in Coastal Dar es Salaam), a three-year project co-funded by the European Commission that aims to improve the effectiveness of municipal initiatives for supporting coastal peri-urban populations in their efforts to adapt to the impacts of Climate Change (CC). The present study is focused on changes in groundwater active recharge in Dar es Salaam’s coastal aquifer, which are attributable to two factors: the decrease in precipitation recorded over the last 10 years, and the change in land cover during the same period. To assess the impacts that these factors have had on active groundwater recharge, the hydrogeological inverse budget was applied, introducing new values for the potential infiltration factor. Temporal analysis of climatic and land cover data for the last 10 years reveal a decreasing trend in groundwater availability. Study results therefore indicate that aquifer recharge is directly related to the amount of precipitation that can infiltrate into the soil, which in turn depends on precipitation and land cover.