This isn't what I was looking for but it's an interesting idea. Water Wheels. Pump driven by the front wheel turning, really large water tanks, forward and rearward squirting action.

The folks fighting forest fires in Wyoming wear water backpacks and brandish hand controlled water wands. Not for fighting the big blazes but great for squelching little smoldering heaps. Maybe there's a use for a team of mountain biking fire fighters?

What I was trying to find was a kit that turned any bike into a water-borne craft. Anyone remember seeing this a few years back? It's from Italy and is called the Shuttle-Bike. A little bit on the expensive side, but then again they manage to fold the whole kit (sans bike) into a little backpack. No word if you can do white-water biking.

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