The Western Cape government revealed the figure in the Cape Town High Court yesterday.

The Residents' Association of Hout Bay and the Habitat Council have applied for an interim interdict against Entilini Concession, the company that operates the Chapman's Peak Drive toll road, to stop the construction of a control building, which will cost more than R50-million.

Residents claim the construction on the route - which meanders through a conservation area and is part of a World Heritage Site - is illegal. They also claim that there are two watercourses close by and that the province did not get permission before erecting office space.

Sean Rosenburg SC, acting for the state, said residents had not raised concerns about the water courses in 19 years.

Rosenburg said experts had dismissed the "water courses" as short, deep mountain gullies but conceded that there were conflicting expert views.

He said there was a risk that the construction company, Murray & Roberts, could pull out of the project because of the disruptions, which could cost the province R141.7-million.

He said the construction of the control building and the toll plaza was scheduled to be completed by July next year but the disruptions could push it to July 2014.

Marie Roux, of the Habitat Council, said: "This wonderful heritage site should not be spoiled by a building that is not for the purpose of conservation."

Judgment was reserved.