Copied from the site...

Seriously, I'm shocked how many of you think this is real.

1) For how steep the hill was + how steep the ramp was, there is no way anyone would get that much speed and launch that far based on sliding alone. Maybe with rockets or something, but not just based on sliding and gravity.

2) The splash caused when the guy supposedly lands in the pool splashes upwards, similar to how it would be if someone canon-balled directly from above. This guy was coming from the side, which means--if it were real--the splash would have sent much of the pool's water off to the right side of the pool... not just a kerplunk.