ABSTRACT
This paper presents results of borehole injection tests in a heterogeneous, fractured quartzite aquifer at Windhoek, Namibia. The main aim is to store high quality water underground for security during drought periods. Four injection tests were done using good quality drinking water from the town’s supply system. The longest test continued for 195 days at an injection rate of 17.1 L/s; the highest injection rate achieved was 60 L/s; and How velocities of 3.6 m/min were measured using tracer tests. Water levels rose by more than 4 m in observation boreholes over 1 km from injection boreholes. The results of the tests are very encouraging and have confirmed the feasibility of high rate injection. The planning of a full-scale borehole injection scheme is underway. This paper presents the test results and the potential for full-scale artificial recharge.
