More than 100 people were killed or trapped in the rubble and twisted remains, around the city there was further death and disruption and aftershocks were continuing.
Against this backdrop, firefighters, police, other official rescuers, as well as passers-by, did their brave best to try to find and recover survivors.
But fire service management, as has been made plain in a report released yesterday by coroner Gordon Matenga, and in earlier inquiries, failed badly.
In the fog of war - for that is what chaos at the scene must have been like - the soldiers fought bravely and did everything they could while the officers were missing in action.
Mr Matenga put it bluntly when he said: ''It is difficult for me to understand why it was felt at the time that one or more of those 13 executive officers could not have been sent to the CTV site to set up a proper structure and provide support for those working there. The officers missed the opportunity to show clear leadership.''
Mistakes in the heat of battle are inevitable.
But the failures that day went well beyond what might be expected.
While the scale of disaster was such the Fire Service could never be fully prepared, the lack of leadership was poor.
Fundamentally, a proper chain of command and incident control point was not set up and communication broke down.
Not surprisingly, the Fire Service now says ''learnings'' - we assume that means lessons - have been taken and it is now much better prepared.
We must all hope and expect so, for surely a catastrophe of this magnitude and mistakes this stark will have shaken Fire Service complacency and inertia.
Is that self-satisfaction why so little appeared to have been learnt from a 2004 exercise to test co-ordination and Usar reaction in an urban disaster after a major Alpine Fault earthquake?
Is that why the results of planning, training and exercises that should be stock in trade came to little when the heat came on?
Among issues on the day were Usar support from Palmerston North and Auckland being delayed (staff were separated from their equipment and arrived after Australian help), police not making a clear handover to the Fire Service, control confusion amplified by dividing the site into two sectors, further problems when Usar arrived about which organisation was in charge and the Fire Service advising Civil Defence international help was not required.
The list goes on.
The coroner in his inquest report into the deaths of eight students - those known to have survived the initial collapse through mobile phone messages or calls but who later died - said ''more people, more resources, better communication and a better structure ... may have improved the chances of saving more lives''.
But Mr Matenga was not satisfied those improvements would have been enough to find the students and save their lives.
In other words, he seems to be concluding that despite the blunders, the students would have died anyway.
There appears here to be some hedging of bets, certainly enough to leave Alec Cvetanov believing the coroner contradicted himself.
He spoke to his trapped wife six times by mobile phone and gave her exact location and believes better communication and direction from senior management would have saved lives.
It is difficult to prepare and train for unlikely events.
It is all so nebulous and all so easy to brush over aspects of the specific permutation planning required.
But, surely, that is a basic role for organisations like Civil Defence, Usar and the Fire Service.
That, simply, is what such organisations must do and do properly.
They must be well led both before disaster strikes and when trouble hits.
Thus, the inevitable mistakes are minimised and a strong framework is in place to adapt to cope with the expected, variations of the expected and even the unexpected.
