Several drivers from the Transpeninsula Investments (TPI) vehicle operating company started striking at 5am, transport mayoral committee member Brett Herron said.
“At this stage the reason for the unprotected strike is unknown,” he said.
None of the buses serving the inner city routes had been running during the morning peak hour as a result. The route linking the Cape Town International Airport to the V&A Waterfront was also disrupted.
The Dunoon-Waterfront route was affected to a lesser degree as only seven of 38 buses were operated by TPI.
Herron said drivers from other companies had been hired to help with route disruptions, but that strikers had barricaded the gates at the depot in Prestwich Street, Green Point.
He said the police was on the scene to help drivers get buses out of the depot. A limited service would run for the rest of Wednesday.