wrote
These guys broke down and dfidn't get out of the "road".
It is about the same as the guys who are changing a tire on a bridge
and get hit by a semi.
I am not really sure what anyone could have done once the barge was in
view. He ain't stopping.

I've seen them stop fairly quickly when they want to stop. Less than the
length of the tow, typically. I'd never count on one to stop for me, though.
If for some reason I found myself stopped in the middle of the river with no
power, the first thing I'd do is start looking to see what's coming. The
second/simultaneous thing would be to get out of the channel, with or
without the boat as the situation dictates. The *last* thing I'd do is stop
looking.