Dam Parameters | Gaborone Dam | Bokaa Dam | Nnywane Dam |
Dam Type | Earthcore Fill | Earthcore Fill | Earthcore Fill |
River dammed | Notwane | Metsimotlhabe | Nnywane |
Year Constructed | 1963, raised 1984 | 1993 | 1970 |
Full Supply Level (FSL) | EL 998 masl | EL 954 masl | EL 1135 masl |
Spillway Length | 272 m | 690 m | 80 m |
Catchment Area | 4300 km2 | 3570 km2 | 238 km2 |
Active Storage | 141.5 MCM | 18.82 MCM | 2.3 MCM |
Surface Area (FSL) | 19 km2 | 6.6 km2 | 1.65 km2 |
Dead storage | 3.71 MCM | 0.25 MCM | 0.002 MCM |
Area supplied | Greater Gaborone | Greater Gaborone | Greater Gaborone |
% contribution to area supplied | 56% | 25% | 10% |