Wellington City Councillor Iona Pannett says $2 million could be wasted on earthquake-strengthening work on the waterfront that is not the council's responsibility.
In June this year, the council agreed to spend $4 million to upgrade Shed Six on the waterfront so conferences could be held there while Wellington Town Hall undergoes quake-strengthening.
Engineering reports now reveal that the wharf piles supporting Shed Six need an additional $3 million worth of quake repairs.
Ms Pannett says council staff have argued that the council should pay for those repairs because the piles also support an events centre, TSB Arena.
But she says the council should fund only the repairs needed to bring TSB Arena up to code and leave the cost of repairing Shed Six to its developers.
The council will debate the subject on Thursday.