Swiftwater rescue is a subset of technical rescue, involving the use of specially trained personnel and equipment to rescue or retrieve people stranded in (or on the opposite side of) swiftly moving water. A typical rescue situation involves rivers swollen by flooding, but could involve crossing any body of water with a similar directional current that must be crossed (hereafter “river”). The pressure of the moving water, usually greater midstream than along the banks or shoreline, makes such rescues difficult and dangerous.
Trained rescuers generally prefer to make “throw” rescues using throw bags or other throw devices to carry a rescue line to a victim. Some rescues are “row” rescues using a tethered boat. When neither a “throw” nor “row” rescue is practical, a tethered rescuer often enters the river in a “live bait” rescue, swimming a line or a floating rescue board to a stranded victim. In “live bait” rescues it appears to be common for rescuers to first build a special safety structure comprising ropes or cables and other mechanical devices across the river to provide tether points for rescue swimmers and rescue boards.
The foregoing methods and equipment are known for being complex, equipment-intensive, and often slow to implement. They require substantial manpower, usually involving teams of rescuers, and significant training. And to the extent that they require a rescuer to enter the water, they can be dangerous for the rescuer.
Prior rescue boards used for swiftwater rescue appear to be essentially longer, thicker, more-protective versions of swimmers' kickboards, with the addition of tether points and multiple handles. Their design assumes that a rescue swimmer will enter the water with the board, often jumping in or riding on top of it, in order to swim the board to a victim.