Flooding and broken-down vehicles caused heavy traffic backlogs in Ekurhuleni on Thursday, metro police said.

Six cars and two trucks were stuck on the N3 Gillooly's interchange, Ekurhuleni Metro Police told News24.

Inspector Kobeli Mokheseng said traffic had also been affected on the R24 and the N12 in both directions.

"We have called our maintenance guys to see if the pipeline is clogged. The backlog has now extended to the R24 and N12 because motorists are trying to avoid the N3. We are doing all we can to divert traffic at this point, but the water is filling up," he told News24.

One motorist told News24 that the traffic had started backing up at Edenvale Road, a few kilometres before the Gillooly's interchange.

"The traffic congestion was also caused by vehicles trying to detour from the N3 to the N12, towards Kensington and into the Johannesburg CBD. It took over 45 minutes to travel between Barbara Road and Gillooly's," the motorist said.

Mokheseng said they predicted the flooding would also affect areas in Alberton.

"The clouds are gathering towards Alberton, so we expect the Geldenhuis and Elands interchange will be heavily affected because of the peak hours. At this point motorists need to exercise patience."

News24