James Street South is currently closed to southbound traffic between Gore Street and Montreal Street.
The CN rail crossing in the area is undergoing some rehabilitation.
The work includes the installation of new concrete panels and the resurfacing of the approach to the crossing.
The work, which got underway on Tuesday, is expected to take approximately four to five days to complete.
During the closure James Street Bridge will remain accessible to southbound traffic through Mountdale Avenue and Montreal Street.
Local access to Kingston Street will be available from Gore Street, and northbound traffic from City Road will not be impacted.
