By the time the firefighters arrived, they were moving down the river pretty quickly.
Except it doesn’t seem like these kids were that smart.
If the current picks up suddenly, there’s a reason, like a waterfall, or an intake pipe or in their case, a hydro-electric dam. Even when the firefighters did arrive, the teens didn’t want to leave their little ice dinghy.
Guessing when they were told that there’s was a good chance they would get maimed, they decided a rescue was welcome.