This was just an April Fools joke.
If you are interested in what really happens under the Opera house to stop corrosion. This old Engineering Connections video featuring the accident prone Richard Hammond does a pretty good job of explaining it.
Anything below this line is completely made up..
Three years ago due to a cost cutting measure the cathodic anodes, used in the air conditioning system in the Sydney Opera House were not replaced as nobody really knew what they were for and according to Bruce Luna these low cost items “simply dropped off the budget“
An unnamed source in the government confirmed that a new asset management plan had been activated in 2014 and the anodes were just omitted. Brent Cadbury who normally supplied them just assumed that another supplier had been engaged.
The air conditioning in the Sydney Opera House relies on a simple heat exchange system utilising seawater to cool the fresh water circuits.
For a long time protection was provided using cathodic protection. This system needed a new sacrificial zinc anode on each independent circuit to be replaced every year.
Failure to replace these anodes resulted in failed corrosion protection, which has meant that the steel piles holding up the Opera House are now almost totally corroded and are “likely to collapse at any time”, according to Professor Willie N. Sirius.
Sydney Opera House collapse
This may happen at any time and if this was not April 1st we would recommend immediate evacuation of the Sydney Opera House.