That is pretty funny.
Not sure about not scraping. It looks like a bumpy ride. Water looked under a foot deep. Just to the hubs of the trucks driving around, to the shins of the pedestrians. Hope it is an old ski.
Other random thoughts.
-The guy is wearing a PFD in 9 inches of water, over an asphalt roadway. But if he hits the curb, and goes head over handlebars, it is his skull that will be crushed. Guess he doesnt own a helmet.
-If I lived or had a shop along the route and he was zipping around kicking up a wake, I'd probably be pissed. Wave action cant be good if you are relying on sandbags to protect your doorways.
Still, it did look fun.