DAMS IN SOUTH AFRICA: Eastern Cape
W Cape E Cape N Cape Gauteng KZN Mpumalanga Free State Northwest Limpopo
Beervlei Dam Groot Rivier/Kouga River/Gamtoos River
Bongola Dam Bonkolo River tributary of the Great Kei River
Bridle Drift Dam Buffalo River
Bushmanskrantz Dam Klipplaat/Oxkraal River tributaries of Great Kei River
Churchill Dam Max. Capacity: 35.5 mil.cub.m. Krom River
De Hoop Dam Kamdeboo River/Sondags River
De Mistkraal Dam Max. Capacity: 3 mil.cub.m. Little Fish River
Doringrivier Dam Tributary of Indwe River/Wit-Kei River/Great Kei River
Elandsjagt Dam Max. Capacity: 106.8 mil.cub.m. Krom River
Grassridge Dam Groot Brak River/Great Fish River
Gubu Dam Kubusi River/Gqunube River
Katrivier Dam Kat River/Koonap River/Great Fish River
Kelley-Patterson Dam Oompies River/Klein Brak River/Groot Brak River/Great Fish River
Kommandodrif Dam Max. Capacity: 58.1 mil.cub.m Tarka River/Great Fish River
Kouga Dam Max. Capacity: 128 Kouga River/Gamtoos River
Laing Dam Buffalo River
Lake Arthur Tarka River/Great Fish River
Loerie Dam Max. Capacity: 3.12 Gamtoos River
Lubisi Dam Indwe River/Wit-Kei River/Great Kei River
Lake Mentz (Darlington Dam) Dam Max. Capacity: 187.7 mil.cub.m. Sundays River

Mtata Dam Mtata River
Nahoon Dam Nahoon River
Ncora Dam Tsomo River/Great Kei River
Rooikrantz Dam In tributary of Buffalo River
Settler's Dam Kariega River
Vanryneveldspas Dam

Pienaars River/Sondags River
Waterdown Dam Max. Capacity: 37.3 mil.cub.m. Klipplaat River
Xilinxa Dam

Tributary of Gcuwa River/Great Kei River
XonXa Dam Max. Capacity: 115.9 mil.cub.m. Wit-Kei River/Great Kei River
 
 

GoogleEarth view of dams in Gauteng

(if GoogleEarth is not installed on your PC, go to the eWISA "Toolbox" for the download address of the free GoogleEarth version)

References: 
Ref 1: