IMO, ignorance can equal negligence..., if you're going out into Gaia's reign you had better have your $hit in one sack and have exercised due diligence by educating yourself on the possible hazards. So-called "dry" river beds are nothing to trifle with.
Would never let the young men (Scouts) in my charge hike in or through them during the seasons when Spring thaws, rains or thunderstorms anywhere near the area were a possibility. In the desert SW we take this $hit seriously, especially during the winter and monsoon seasons.
Condolences to the families and RIP to those whose lives were lost.
