The work, scheduled to begin on Monday, April 3, is part of Northumberland County Council’s masonry arch improvement programme.
The information gathered will enable the council to design a scheme of restoration work aimed at securing the long-term future of the iconic 17th century bridge.
Pedestrian access will be maintained at all times and the Grade I listed bridge will be fully reopened in time for Friday, April 14 and the Easter weekend.
The council has liaised with key stakeholders, including the local traders association, and has agreed to do this work before the start of the main holiday seasons.
The Old Bridge is the main exit route for southbound traffic from the lower part of Berwick. An alternative route via the Royal Tweed Bridge will be signposted for use during the closure. Northumberland County Council said that it appreciated the works may cause some short-term inconvenience.
A spokesperson said: “We understand the importance of minimising disruption and will be dedicating extra resources to this scheme, including working weekends, in order to reopen the bridge as soon as is practicably possible.
“We hope that residents, visitors and businesses will bear with us during this essential closure.”