When these tragedies occur the infrastructure has failed. We see this all the time, especially with rain. The infrastructure in western North Carolina not only failed it was destroyed. Roads were gone. People stranded. Some rescuers used horses to reach the people because horses defy the need for infrastructure. Not that it isn’t dangerous, but, pack mules escorted by riders on horseback provided more immediate relief.
This tragedy in Texas is a bit different. Tragic, but, different. Geologists at some point need to evaluate the headwaters that caused this tidal wave of water and debris. Understanding what occurred here can prevent the next one.
Right now the river and land are unstable and the heavy equipment is to reverse that to facilitate the search. But, even these in roads of hope may not be permanent. That wall of water came from somewhere and not just the sky. The best thing that can happen is for local people to move away from lower elevations until it is known this can’t happen again. In some ways the debris is more of a killer than the water. That is what occurred in North Carolina and it sounds, from reports, that is what happened here as well.