For reasons only partially understood, I decided to briefly cruise the net for booms and swiftwater rescue. I found the use of inflated, nearly rigid fire-hose-type devices being hyped.

There were not a lot of written details but pictures and diagrams clearly showed lengths of inflated fire hose being fed straight out to victims in still water, and being fed upstream to drift down to victims in moving water, among others. One diagram even shows tethering the hose upstream to a tree and using what they call the pendulum effect and guide ropes on a mechanical truck boom over the water to let the current take the hose to a victim.

I did not find any river-crossing mentions, nor the idea of having a rescuer ride the end of the inflated fire hose as the current pendulumed it out.

Sounds a bit like a high-tech "pole" to me.