Residents and staff at the Centurion Hotel in Pretoria had to be evacuated due to heavy flooding this morning, the Tshwane community safety department said.
Spokesperson William Baloyi said everybody had to leave the 160-room hotel around Centurion Lake.
The owners had been advised to have an engineer examine the building.
Emergency services had also been advised that although some streets had been reopened, the Rietvlei dam was 101% full and the flood gates might have to be opened.
This would put further pressure on the Hennops River, which flows through south east Pretoria, which is a mixture of urban housing and smallholdings.
In the meantime, rescuers were moving through the area trying to make sure everybody was accounted for.
Earlier, Baloyi said they had had to rescue four people who had been swept away by the strong waters.
They were trying to trace at least eight other people.
They were hoping the eight had decided to sleep elsewhere for the night and go straight to work.
Police were phoning their workplaces to establish that they were safe.
In Ivory Park closer to Johannesburg, 34 people had to be evacuated from the Thambakazi informal settlement.
The SABC reported that schools at eight villages in the Mutale area in the Vhembe district of Limpopo were closed due to flooding.
Teachers and pupils were unable to reach the schools in Damani, Tshipaeko, Mkwarani, Vhutalu, Tshidzivhe, Tshilungwi, Tshitangani and Mudzidzi.