“There is water all over Bela Bela, rescue efforts by the police and the municipality’s emergency services are underway,” said spokesman Brigadier Hangwani Mulaudzi.
Helicopters were used to rescue residents from the area. A nearby informal settlement was severely affected, with no injuries or deaths reported, Mulaudzi said.
Last week, the dam overflowed, sending waves of water into the streets and homes.
An elderly couple were washed away on Friday at the resort Klein Kariba outside Bela Bela when another dam gave way after persistent rains the past week.
They were swept away while swimming in an undercover pool.
The search for the 69-year-old woman continued. The body of her 74-year-old husband was found on Saturday.
Mulaudzi said the road between Bela Bela and Modimolle was filled with debris and was not suitable for use by motorists.