Transnet anticipates that it will take close to two weeks to clear the backlog at Ngqura Container Terminal, which has been hit by illegal strikes, the state-owned company said in a statement on Friday.
Operations have nonetheless improved at the Durban Container Terminal and Port of Cape Town, it added.
Staff embarked on a go-slow at the facility earlier in the month, to which the entity responded with the suspension of employees, Fin24 previously reported.
To date, 13 employees have been suspended, Transnet said.
The industrial action was over the payment of a short-term incentive and other related matters, including equipment failures and transport.
"Following a court interdict, productivity is returning to normal," Transnet said.
However, it added, the industrial action "had a negative impact on customers, in particular the agricultural and automotive industries". Vessel owners and operators servicing the container industry have also been affected, and Transnet is working with them to prioritise cargo despite persistent "performance challenges" in certain critical areas.
Transnet was a "key cog" in the SA economy whose role could not be over-emphasised, the statement added.