I saw one last year at Lake Wintergreen. A club for UNH had built one and were practicing paddling it in preparation for a contest with other schools. They looked quite wobbly. I shared some sculpture tips on how to make the concrete lighter so I hope they won.

: A concrete kayak....well, a canoe.
: One hundred and forty pounds and fast-fast-fast!
: TwoPaddles, are you listenin'?

: Check it out at:
: http://www.concretecanoe.org/TipsandStrategy/Carnivale.pdf