Dunedin City Council is not sure when the St Clair waterfront will reopen to the public after sea surges undermined the pavement along the Esplanade, causing large holes.
The holes were first noticed next to the surf club ramp on Sunday and have grown bigger since with one now several metres wide.
The council says sand under the pavement has been washed away by recent surging ocean swells combined with high tides, and the paved areas affected have been cordoned off for public safety.
The council's manager of transportation operations, Graeme Hamilton, says the main priority is to stop the holes growing further and staff have been working to try to prevent any new erosion.
He says they will then make sure the sea wall is still as strong as it needs to be, before the holes are filled in.
Mr Hamilton says the council has no solutions or costings yet and does not know when the area will be repaired and public access restored.