Routine maintenance checks this morning discovered a fault with a switch which enables essential backup generator power to Christchurch Hospital Parkside West.
It is suspected the reason for this problem is quake-related damage to the switchboard.
Dr Nigel Millar, CDHB chief medical officer, says the fault needs to be repaired and this means taking essential power offline for a period of time.
"This work is scheduled to take place tomorrow morning from 8am. At this stage we don't know how long repairs will take but don't expect it will be more than two hours," Dr Millar says.
While the repairs are underway, all non-essential power will still work during this time unless the network has a major outage. Non-essential power is power to areas such offices and storerooms, he says.
"We are implementing our contingency plans this afternoon. This means three elective surgery theatre lists have been post-poned, affecting about 10 patients.
"Arrangements are in place to divert acute referrals received from other South Island DHBs as appropriate during the next 24 hours as an extra precaution.
"Plans are also being made to ensure inpatients in the affected areas will continue to receive safe care. This may mean some will be moved around the hospital to areas where there is essential power."
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