I've heard about the canal water skiing before from folks who live in the Bakersfield,CA area. They said it was fun until you hit a cross pipe or fence!
Actually, those guys doing the ditch thing do some pretty good tricks.
Reminds me of growing up in south Florida where we did some serious canal surfing behind whatever could pull us down the levy!!! Usually it was a Suzuki 185 dirt bike with a rope tied to the back of the frame. Did some crazy stuff back in the day...
Without a wake to hit and catch air, I would think it would get pretty boring after a run or two. How about building a ramp or rail in that ditch, now your talking.