In media when an out of control car runs over a fire hydrant the inevitable result is a geyser of water that instantly adds both drama and excitement to the scene. In reality the most likely result is a good deal of front end damage and a bill to repair the broken hydrant, but in a non-trivial amount of cases the car will wind up as an aquarium. What determines if this trope is Artistic License or Truth in Television is the design of the hydrant. Hydrants known as "wet barrel" bring highly pressurized water all the way up into the part that sticks above ground. Hydrants known as "dry barrel" keep the vital valve equipment many feet underground, which are then opened via a long shaft.
Any location subject to cold temperatures must employ dry barrel hydrants to avoid problems with burst pipes. This combined with the protection against the very calamity that the Hydrant Geyser portrays is why dry barrel hydrants make up the overwhelming majority of installed units in North America. Of course with wet barrel units being acceptable in warm locations such as Southern California, that design makes up the majority seen in media, hence the popularity of the trope.
This trope is constantly hovering on the border of becoming discredited or even a dead horse with spoofs and parodies making up a large number of examples, however it is frequently played straight both in media and Real Life. Like the exploding car, this trope maintains a strong grip on the popular psyche causing people to be genuinely surprised when hydrants are knocked over with little fanfare.
The presence of a Hydrant Geyser can always be Hand Waved away by saying that any given dry barrel unit was accidentally left pressurized via an open valve.
Often the geyser is preceded by a comical rumbling of the ground as if Hydrant acted as some sort of champagne cork or oil well. This is always wrong as a pressurized hydrant will instantly gush water, not take a few seconds to "get going".
- In the Dynomutt story "The Incredible Mr. Mastermind" (Marvel, issue #2), Blue Falcon finds himself on top of a hydrant geyser after Dynomutt knocks it over. But it's not Dog Wonder's fault—Mastermind has taken remote control of him.
- Happens during the "Do I feel lucky?" bank robbery scene in Dirty Harry. Bonus points for the car also wrecking a flower stall at the same time.
- In The Blues Brothers a geyser is seen to erupt after the police car collides with The Good Old Boys Winnebago after the Blues Brothers flee the Country Bunker.
- In Superman III the action opens with an out of control car knocking over a hydrant, which proceeds to fill the passenger compartment with water and threaten to drown the person trapped inside.
- In RoboCop (1987), when the Boddicker gang are playing around with their Cobra Assault Cannons, one blows the top off a fire hydrant causing a geyser.
- In Bruce Almighty, Bruce uses his God powers to knock a hydrant over, allowing some kids to play in the resulting geyser.
- Towards the end of Lethal Weapon, when the cops are shot in front of Murtaugh's house their car rolls into a hydrant that creates the geyser that then creates the mood for the ultimate fight scene.
- In Ghostbusters (1984), Stay-Puft knocks one over and gives his rampage a touch of realism. note
- Demolition Man hands us a very peculiar one as Simon Phoenix takes a shot with his newly-acquired BFG and decapitates a fire hydrant, resulting in the expected geyser. The catch is that this particular hydrant was in an archaeological dig of an LA street buried when the Big One earthquake struck. Meaning the entire city was destroyed and buried and yet somehow this hydrant still had pressure. Ragnarok Proof, indeed.
- In an episode of CSI: Miami a hydrant geyser threatens to wash away critical evidence after a motorist was shot (thus causing the geyser).
- Scorpion: In "Revenge", Happy deliberately creates a hydrant geyser by knocking the cap off a hydrant, and using the resultant jet of water to knock two fleeing bad guys off their motorcycles.
- At Universal Studios:
- The former Kongfrontation attraction at Universal Studios had a broken fire hydrant shooting off water down in the streets, to show off the damage King Kong had done there.
- A fire hydrant also gets broken and shoots water during the Hey Arnold! sequence in Jimmy Neutron's Nicktoon Blast, a water effect would then be used to make the riders feel as if they're getting sprinkled by it.
- This would occur in the also-defunct Twister...Ride it Out attraction when a car gets pulled forward by the tornado, dislodging a fire hydrant in the process.
- Both Teenage Mutant Ninja Turtles: The Arcade Game and Teenage Mutant Ninja Turtles: Turtles in Time allow you to send water flying out of a hydrant, damaging any enemies in its path.
- Several Grand Theft Auto games will do this if you hit a hydrant at any significant speed. Like fire engines and police water cannon, the water has a knockdown effect on anybody it hits.
- In Resident Evil 3: Nemesis, Jill passes by a busted hydrant on her way to the police department. By the time she comes back (a few minutes in real time, but several hours in-game) the hydrant has run out of pressure and the there is no more geyser.
- One of Pac-Man's special move in Super Smash Bros. for Wii U and 3DS makes him summon a fire hydrant which then sends short spurts of water on its sides, pushing the characters on the way. If Pac-Man stands atop the hydrant, a little geyser will push him upward. This move is based on the 1984 arcade game Pac Land in which hydrants are obstacles, though the upward geyser is completely new to this game. A bit subverted as the water spurts if the Hydrant is not destroyed. Of course all of this does not make any sense and is just for the sake of the game mechanics.
- In the second part of Road of the Dead, shooting a hydrant and driving through the geyser is the preferred way of putting out a burning engine.
- Parodied in The Simpsons episode 22 Short Films About Springfield Chief Wiggum, on foot, recognizes Snake at the wheel of his car at a light and in the ensuing attempt to flee Snake crashes into a mailbox which results in a geyser of letters spewing forth from the ground.
- This was a Running Gag in the Rocko's Modern Life episode in which Rocko teaches Mrs. Wolff how to drive; she would keep running into hydrants, which fill the car with water.
- In Batman: The Animated Series, Mr. Freeze kicks open a fire hydrant and fires his Freeze Ray at the geyser to create a rapidly rising column of ice that he rides up a skyscraper. The animators admit it's unrealistic, but it looks really cool.
- In the Darkwing Duck episode "It's a Wonderful Leaf", Darkwing accidentally rips a hydrant off the pavement when he gets his beak stuck on it, and he uses the ensuing geyser to soak and freeze Bushroot and his army of living Christmas trees.