The company is struggling to provide sufficient freight rail and port capacity to transport bulk minerals coal, iron ore, manganese and chrome to export markets as its rail operations are hobbled by shortages of locomotives and spares as well as cable theft and vandalism. Ports operated by Transnet have also struggled with bad weather and underinvestment in equipment.
Transnet was suspending ship booking services for coal loads brought by trucks at least until current bookings, which run up to February 2024, are cleared, said Richards Bay Terminal's managing executive Thulasizwe Dlamini.
"We have seen an unprecedented number of trucks coming to the terminal. We will temporarily freeze vessel nominations," Dlamini told a media briefing, using the industry term for booking shipments.
A surge in demand for coal in Europe and Asia over the past two years, and particularly since Russia's invasion of Ukraine last year, has brought hundreds of trucks onto the route leading to South Africa's main coal export terminal in Richards Bay on the east coast.
The high volumes of trucks rolling into the port were disrupting business, causing congestion on the roads and raising safety problems for the municipal authorities, Dlamini said.
"The intention is not to frustrate the movement of coal out of the country, but to create order," he added.
Mining companies, which say they have lost billions of rand in potential export revenue due to Transnet's infrastructure problems, have resorted to trucking minerals to ports, a more expensive and environmentally damaging option.
In 2022, about 41 million metric tons of mineral ores, requiring the capacity of nearly 1.4 million 30-ton trucks, were transported to South African ports by road, according to the country's Minerals Council.