The Tay Road Bridge could need almost £4 million spent on resurfacing its carriageway.
Councillors on the bridge board heard that tests of the asphalt using ground-penetrating radar have been completed and the results are being analysed.
Core samples will be taken this month to help work out how much of the current 47-year-old surface needs to be replaced.
The expansion joints at the end of each span of the bridge have reached the end of their design life and they will also have to be renewed.
Bridge engineer Fergus Wilson said he hoped to bring a full report to the next board meeting in December.
At this stage there is no indication of the likely timetable for the work, or what it might mean for drivers in terms of restrictions or lane closures.
Most of the asphalt on the carriageway dates back to 1966 when the bridge opened, although a surface dressing was applied to it about 20 years ago.
The radar survey will provide a 3D picture of the carriageway, showing any cracks or other signs of deterioration.
Mr Wilson said: “What we will be doing now is core testing of the asphalt overnight this month to verify the radar survey.”
The board has set aside £3.95 million in the bridge’s capital spending plan for the current financial year and 2014/15 to carry out the resurfacing works and fit new expansion joints.
Separate works costing £113,000 are already under way to repair the concrete deck, road surface and expansion joints on a section of the bridge’s northern approach viaduct. This includes protective coatings and waterproofing.
Mr Wilson told the board that the removal and reconstruction of the bridge ramps as part of the Dundee central waterfront regeneration has been going well, with demolition materials being recycled.
“Construction of the eastern side of the new approach ramps and new South Marketgait bridge is due to start shortly. This element of work is programmed for completion by December,” he said.