Motorists using the Clydevale bridge next week could face delays of up to 40 minutes.
An inspection of the bridge will be carried out between 8.30am and 5pm on Wednesday, and the Tuapeka Punt will be available between 8am and 6pm as an alternative river crossing for light vehicles, at no charge.
The Clydevale bridge, which spans the Clutha River, 22km northeast of Balclutha, has been subject to speed and weight restrictions since November last year, when an inspection found structural damage.
A speed limit of 10kmh is in force on the bridge, and an overweight permit is required for vehicles exceeding 50% of class one loading (maximum 23 tonnes).
Clutha District Council communications co-ordinator Jamie Shaw said this week's inspection was part of an ongoing investigation into the bridge's future.
The Clutha Valley structure, which was built 75 years ago, is scheduled to be replaced within the next five years.
The council is weighing up whether to spend money on improving the existing structure or replacing it.
The inspection would be dependent weather and river conditions.
If it could not be carried out on Wednesday, it would take place on Thursday, Mr Shaw said.