Vaal Dam is overflowing
The Vaal Dam is 101 percent capacity and flood gates have been opened,, the department of water affairs said.
"Four flood gates [were] opened by 8am this morning," said departmental spokeswoman Linda Page.
The Bloemhof Dam in the Free State is at 97 percent capacity and the Gariep at 95 percent.
The Gariep is expected to reach 100 percent capacity on Wednesday.
"The Department of Water Affairs is urging all communities to exercise caution in the vicinity of the Vaal Orange River System and affected dams.
"It is also advisable to refrain from participating in recreational activities until further notice."