Schools in Nelson Mandela Bay were closed on Wednesday after torrential rain caused severe flooding. Some businesses also closed their doors.

The CEO of the Nelson Mandela Bay Business Chamber, Denise van Huyssteen, said bigger manufacturers were able to continue production but many employees had stayed away. Severe floods damaged factories, offices and warehouses, she said.

"Some manufacturers have opted to close their factory doors ... and businesses whose operations allow for remote working have done so until the adverse weather risks subside."

The Nelson Mandela Bay Civil Society Coalition complained that the municipality's emergency fleet had been left without fuel after a failure to renew a fuel supply contract, "effectively grounding critical response operations at the very moment they are needed most".

"This is not an isolated administrative lapse. It is a dangerous collapse of governance with real and immediate consequences for vulnerable communities," said the coalition.

The municipality confirmed that fuel reserves were low but said it would source enough fuel to respond to emergencies caused by the flooding.

"Priority will be given to critical and frontline services, including emergency response and disaster management," said the municipality in a statement.