I assume the " Arrowhead trail " you make reference to is the one that goes from DCHS up to HWY173 at the Kinely Creek Bridge. I've only heard of that trail being called the Bradford Ridge trail. I figured the report had to be wrong about them washing down the stream because that would be quick and certain death in the kind of flooding that was occuring that day. From what you describe, it doesn't sound like thier " camp " got over-run by the floods either. Sounds like they just found themselves stuck because of the high flood waters on Sunday morning. Did they lose any of thier gear in the flooding? If they were unfamiliar with the Bradford Ridge trail, or the option of hiking down the PCT and across the Mojave Forks Dam to Lake Arrowhead Rd, then it sounds like they chose the best course, that being waiting for the rescuers. Gotta tell your cousin and friends to watch the weather forcast when they hike to DCHS because as they found out, the water can rise fast. Glad they all made it back safe from thier adventure :-)