On the news this morning is that the two buildings CTV and PGB were built on land that is prone to liquifaction. This stuff has been a significant problem in this crisis, oozing up over the paving in thousands of tons, and currently dried out and blowing around. News footage shows most people wearing dust-masks and safety glasses, all over the affected area, not just rescuers in the inner city.
There was a glimpse of a tanker truck spraying water on the TV. Directly behind the anchor man. Bet it got him.

No thanks are enough for the support we have received from around the world. Rescue teams from as far as 11000 miles away are here.
Australia could not be more supportive if NZ was part of their country, with a military field hospital set up in case of epidemics, police officers augmenting ours, and several S&R teams, and the offer from Adeleide University.
Many students are currently shovelling dried-up liquifaction in the suburbs.