Empty Swimming Pool Dive

"Maintenance worker, to diver: Are you going to dive into the pool? Diver: No, I'm going to dive into my martini glass over there.

Maintenance worker: (putting up "Pool Closed for Repairs" sign while diver dives) Good. At least that's not empty."

- Mad Magazine: Snappy Answers to Stupid Questions

You know the gag. A person makes a masterful dive into a swimming pool, discovering too late that the pool doesn't have water in it. Physical trauma (and possibly hilarity) ensues. It's fairly popular in comedy, and typically Played for Laughs, although more dramatic examples do exist.

A common subtrope of High Dive Hijinks.

Advertising
"Before you go and do something you've never done before, you'd just better know...what you're jumping into."
 * This anti-drug public service announcement is a rare serious take on the trope.

Comic books

 * A more serious example in the Franco Belgian Comics Les 4 As: In one book, a mafia gang used that as a method of execution.

Literature

 * This trope was the punchline of one Shel Silverstein poem.

Urban Legend

 * There's a story of a boy who practiced diving into a public pool at nighttime. One time as he was about to dive, he noticed he was casting a shadow in the shape of a cross. Believing it to be a sign, he hesitated. Moments later, the lights came on... revealing that he'd just barely defied this trope. Read about it here.

Video Games

 * You can do this deliberately in one stage of Zack and Wiki: Quest for Barbaros's Treasure. In fact, you have to in order to get a certain achievement.

Western Animation

 * In the animated version of The Grinch Grinches the Cat in the Hat, one of the lines from the Cat's song speculating about why the Grinch is so grinchy is "Did you dive in an empty swimming pool?"
 * Whenever a Looney Tunes or Tex Avery short features a pool with a diving board, you can bet this trope will appear in one form or another.
 * The 3rd episode of The Flintstones (actually the first one produced) was titled "The Swimming Pool", where Fred and Barney build a pool in their adjoining backyards. This gag appears at least once.
 * Turns up in many a Tom and Jerry cartoon, e.g. "Salt Water Tabby".
 * Happens in the Classic Disney Short "How To Swim", when Goofy is demonstrating the high dive. He leaves a Goofy-shaped hole in the floor.
 * There was a Pink Panther cartoon short that consisted of a series of unrelated gag clips. In one, the Pink Panther climbs a diving board ladder and dives into a pool (with irrelevant results). Then he ascends the ladder again but continues on past the first board to a (much) higher dive platform. Between the time he jumps off the board and reaches ground level, the filled pool suddenly and inexplicably drains completely. Elapsed time: about 2 seconds.
 * In the Looney Tunes short "High Diving Hare" Bugs Bunny tricks Yosemite Sam into jumping off a high dive into a barrel of water, except there's no water in the barrel. Bugs dumps a bucket of water after Sam, and Sam tries to get the water to fall faster than he so it'll be there for him to land in. The water lands on the barrel in time... Sam misses the barrel entirely.
 * A Tiny Toons short involving Montana Max stealing water for his own pool had a few instances of this.