Total annual water generation in the country amounts to over 23 billion cubic meters, which is mainly replenished through rainfall and runoff into rivers, streams, lakes, aquifers, reservoirs, and wetlands. The country relies significantly on its surface water resources (about 90%) due to limited ground water resources (about 10%). There are seven river catchments in Zimbabwe, namely Gwayi, Manyame, Mazowe, Mzingwane, Runde, Sanyati and Save. There are over 8000 dams in the country; however, 149 large dams account for 80% of the allocated water to storage. The impacts of climate change on Zimbabwe's water resources could be diverse. For example, changes in runoff could limit hydropower generation; increasing temperatures may increase water demand for agriculture and energy generation; decreasing rainfall could increase the cost for water treatment and wastewater management; and climate change might lead to more frequent and intensified natural hazards including floods and droughts. Water availability could be tremendously affected by changes in annual precipitation. A small decline in mean annual precipitation could potentially lead to a significant drop in mean annual runoff and groundwater recharge.
This section provides insights into projected climate change impacts on various hydrological indicators.