Artificial groundwater Recharge in Botswana - A Feasibility Study and Capacity Building

Research Project, 2012 – 2014

Due to evaporation Botswana loses about 70 % of the drinking water collected in surface water dams. The overall objective of the project is to investigate how artificial recharge of groundwater can increase the water supply safety for urban areas in Botswana.

A water supply safety model is developed for the area along the North-South Water Carrier supply system of eastern Botswana. The model includes a dynamic water balance model where statistically generated time series of the availability of source water for artificial recharge (inflow minus losses) are used together with dynamic storages in artificially recharged aquifers and water demand to simulate magnitude and probability of water supply shortage. The existing water supply system will be the baseline and artificial recharge options will be included to be compared with the present day situation in terms of incremental increase in water supply security and water savings. The structure of the dynamic water balance model to be developed will be based on a similar model developed for the Central Area of Namibia. Using the model, a number of potentially interesting artificial groundwater recharge scenarios are identified, modeled and compared in terms of increase in water supply security, water banking and cost.