I am not an architect or a brick mason, but I do not think it is a coincidence those buildings 75 years and older are collapsing after a week of heavy rain.
The mortar used back in the day was porous and softened with age. Mortar used today is not as porous and hardens over the years.
Unless the buildings like in the French Quarter are water-proofed, they will continue to collapse after a monsoon like we frequently have.
JOHN BENFATTI
Slidell