I found this
The WaveWalker Minnesota - Hydroped
Pedal powered kayak. The propeller unit is retractable for landings. Supposedly cruises at 5 mph, does 9 mph for a good cyclist. Either is ripping fast vs a regular kayak. Video below. I sort of envision having a standard kayak paddle, for bracing strokes, launch/land, extra speed.
Worlds Fastest Pedal Powered Production Kayak. - YouTube