In the first, on the M5 near Rondebosch, two people were injured and the driver, 30, was killed when their car went flying into a bridge in the early hours of Sunday morning.
According to witness Cheryl Matthews, 46, from Wynberg, the bright red Opel Corsa was weaving through traffic “at a tremendous speed” before it went flying through the air, and lodged in a groove under the bridge at the canal at Klipfontein Road.
Traffic spokeswoman for the City of Cape Town, Maxine Bezuidenhout, confirmed the M5 crash.
"One person has died in a motor vehicle accident on the M5," she said, "when a car drove into the bridge at the Klipfontein exit.”
Matthews said: “I couldn't believe the speed they were driving at. And from the erratic movements, the driver was definitely drunk. I will never understand why you would put yourself or your passengers in such a position. I heard the people say the driver was drunk.”
The mangled car was removed at about 10am on Sunday.
In another incident, a car landed in the canal at the Cape Town International Convention Centre. It's not clear how the car, which looks like a Toyota Corolla, landed up in the water.
Traffic authorities did not respond to queries about this incident on Sunday.