The Canterbury District Health Board is facing an $80 million repair bill, following earthquake damage to more than 7500 rooms in two of its hospitals.
The estimated bill, which will be mainly covered by insurance, excludes extra work needed to bring buildings up to the new seismic code.
Canterbury DHB chief executive David Meates says it is likely some staff and patients will have to be moved temporarily if repair work becomes too disruptive.
The hospital's riverside and parkside blocks, as well some of Princess Margaret Hospital, will undergo the most major repairs.
Mr Meates says work has been underway for months and could continue for another two years.