That's pretty frightening.
Floods are an act of Gd, but how one copes shows the true qualities of man.
My parents spent their final years in senior citizen places of various care levels in Arizona from "independent living" to "full care with locked door." The residents are totally dependent on their caregivers, and the management had a lot to deal with. Many of the places were branches of enormous businesses. I wonder how they would have dealt with such an emergency. Since the staff all live at their own homes and many would have to flee with their own families, who would be available to care for the helpless residents?
When a different American city had been flooded, a friend of mine discovered that her elderly mother had been put on a commercial bus by the "home" she had resided in and sent to a safer city. The family had to rescue her from there. As traumatic and dangerous as that had been, it was a lot better than what happened in this senior citizen facility.
Apparently, Hurricane Harvey is much more devastating than predicted. I have no doubt that there are people who were incapable of leaving their homes or trusted that they'd be safe on an "upper floor." I hate to think of the unpleasant surprises to be discovered when it all settles.