The seawall along Stokes Bay, adjacent to the Alverbank East Car Park, was damaged in early January and has been closed off ever since.
Work is expected to take around two weeks, with the footpath behind remaining open to the public.
Cllr Graham Burgess said: ‘I’m pleased that the work to this area has started and should be completed swiftly to allow access to this area again. We’d like to thank residents in advance for their co-operation.’
The lower walkway on the Western Promenade remains closed while options for repair are considered.