Abstract: The main cause of climate change in Zanzibar is rapid population growth, which has driven up the emissions of Carbon dioxide. Since 1980s, the demand of water for Agricultural, Industrial, urban use has been on an increase. This has resulted in the exploitation of underground water without consideration for recharge. Consequently, the water table has continually lowered. Zanzibar, being an island, is poorly endowed with surface water resources such as rivers and lakes. This means that the only other source of water is precipitation.