A 10kmh speed limit for the Galloway Bridge, over the Manuherikia River near Alexandra, has been imposed after cracking was found in a pier head.
Central Otago District Council roading committee chairman Graeme Bell said the fault was identified by Fulton Hogan during recent work carried out on the riverbed.
The speed limit will remain in place until further notice and investigation work is expected to begin on June 11.
It should take two weeks to complete.
"This is not an emergency situation and there is no need to close the bridge.
"However, it is better to get this work completed now to ensure residents and road users have access to the Galloway area," Mr Bell said.
Council Roading Engineer Peter Cuthbertson said reducing vehicle speeds on the bridge would help ensure the safety of bridge users.
"It is anticipated that there will be no weight restrictions or closures of the bridge while the work is carried out," Mr Cuthbertson said.
