Johannesburg - Pikitup workers embarked on a go-slow on Wednesday, with the company confirming it was not running to full capacity.
"We have not received a formal notification as management into the reasons, but are engaging with employees to find out what their grievances are," spokesperson Desiree Ntshingila said.
"We have adopted the no-work, no-pay principle and have contingency plans in place to cover up the backlog. At this stage we are not running at full capacity."
On its website, the company said refuse collection in Randburg, Norwood, Avalon, Roodepoort and Southdale had been affected since July 1.
However, the exact areas affected would be available only on Thursday, Ntshingila said.
Pikitup is the City of Johannesburg's waste management company.
Ntshingila asked residents to be patient and to hold back their bins until the go-slow was over.
"Pikitup will collect the waste from the 240 litre wheelie bin as well as additional refuse bags when the refuse collection schedule commences," she said.
"It is unclear as to how long the workers will be on a go-slow for, but management is working to resolve the matter with the Pikitup workers."
Contingency plans to collect all the outstanding waste and would be communicated soon, she said.