I agree - seems pretty set up. The very last clip of the three runners really gives it away - if you watch the rearmost runner he actually jumps up and into the water hole. The second bike rider also does some strange pre-water hole turn of the handlebars prior to going into the hole. I think if I were swallowed up by a water hole that was never there before I would be freaking out instead of laughing. So, now we find ourselves firmly entrenched in "fake" reality TV.
Usually in these TV pranks, they edit out the angry responses. You also sign a release form after the prank to give the TV channel the rightr to show your face. We never see all the pranks.
They also do a few fake ones for extra fun.
Pretty foolish on the part of the folks that set this up. What would they do if the individuals couldn't swim? I'd sue ther pants off!
"Skill without imagination is craftsmanship and gives us many useful objects such as wickerwork picnic baskets. Imagination without skill gives us modern art." - Tom Stoppard