A major toll plaza is on the drawing boards near Cato Ridge on the Durban to Pietermaritzburg section of the N3, the crucial road artery linking Durban harbour with Gauteng.
The South African National Roads Agency Limited (Sanral) has yet to inform the public about the Cato Ridge toll plaza, and agency spokesman Neil Tolmie denied on Friday that there was "anything on the cards as yet".
However, the Independent on Saturday has uncovered documents which show the agency pencilled in the location last year, and is expecting substantial opposition to the plan.
According to minutes of a meeting of the Brandekruin Sakekamer held in Aman-zimtoti on October 28, Sanral regional chief Neil Tolmie let slip the Cato Ridge plaza was under consideration because of a major national roads funding crisis.
Tolmie told members of the Amanzimtoti business chamber - many of whom are up in arms over a proposal to build a toll plaza on the busy N2 freeway just south of Durban International Airport - that the national roads agency had accumulated a debt of about R5 billion in recent years.
Yet the government was allocating just R1-billion a year for the maintenance of the country's 7 000km-long national roads network.
About 2 000km of the total national network is already tolled.
Tolmie was quoted as saying his agency was seriously under-funded and that "tolls are the only way to receive (adequate) funds", according to the document.
Tolmie told the meeting he was expecting controversy over the location of the new plaza "between Cato Ridge and Pietermaritzburg", a site on a busy commuter section of an existing road.
But under the National Roads Act of 1998, the government is no longer legally obliged to provide a free alternative road when it decides to toll existing sections of the country's roads.
On Friday, when the Independent on Saturday contacted him for official comment, Tolmie said: "I'm not sure in what context this might have been raised... it could have been mentioned in a broad context."
Asked to explain why the minutes were quite specific about the location, and quoted as saying he expected a controversy, Tolmie said: "There is always a possibility of tolling any road in the country, and these things could come up.
"But should there be a decision, then we would have to go through the legislated process of conducting an environmental impact assessment and publishing our intention to toll.
"We would also have to involve the minister and the board before going public with any proposals," Tolmie added.
The traffic volume passing through the Mariannhill plaza now is about 30 000 vehicles a day, while the figure for the Cato Ridge area is thought to be about 27 000 vehicles a day, compared with about 14 000 a day at the Mooi River plaza.
The combined toll fees for a car travelling between Durban and Johannesburg already exceed R100.