A water cannon is a device that shoots a high-velocity stream of water, which is frequently used for riot control. This weapon evolved from the use by authorities of fire hoses to quell riots in the late 19th and early 20th century.
Sometimes in fiction, a character (almost always The Hero) will still use a fire hose (or other high-pressure water source) as an Improvised Weapon. In most cases (especially if the wielder is The Hero) the target will be an individual or small group rather than a mob.
Compare Making a Splash, where characters can do this without a hose.
Very much Truth in Television as any firefighter can testify to the concussive force of a stream from a high-pressure hose, and the difficulty of getting back to your feet if you are being bombarded by it.
- In Bet Your Life, Sonny uses the deluge gun on a fire boat to knock Joseph out of his helicopter: firing the stream of water in one door and out the other.
- Near the end of City War, after Ken had killed off all of Ted's henchmen in the abandoned bus depot, Ted ambushes Ken with a high-pressure hose (used for cleaning vehicles) and tries to drown Ken alive. The timely intervention of Ken's grievously-wounded buddy, Dick, who turns out to be Not Quite Dead, is what ultimately saved Ken's life by tripping Ted from the back.
- The Delinquent: During the warehouse raid when Boss Lam's minions attacks the warehouse Shum works as a night watchmen, Shum briefly uses a water hose turned at full blast to defend himself from a bunch of thugs. It works for a short while, but a thug who entered from the back door hacked the pipe and stopped the water altogether.
- In First Blood, one of the tortures the deputies subject Rambo to in the cells is blasting him with a high-pressure fire hose.
- At the climax of Herbie Rides Again, Alonzo Hawk's attempt at bulldozing Grandma Steinmetz's firehouse with her in it is temporarily slowed down by Grandma and the man she's dating using the firehouse's hose to toss the operators off their construction equipment until the hose bursts from overuse. Hawk only has a few seconds to gloat that they can't stop him before Herbie (and all of the Beetles in San Francisco) attack.
- Mannequin: Hollywood uses a fire hose to hold off a bunch of security guards so Jonathan can save Emmy from being killed in a trash compactor.
- The Man Who Knew Too Much: Alfred Hitchcock reported that the London police, who were cooperating with the production, objected to the police being shown using guns against the criminals holed up in house behind the temple. When he asked them how they would deal with it, they suggested using fire engines and hoses: a technique which had been employed in the Siege of Sidney Street in 1911. Eventually, the police agreed to the scene showing the police using rifles, so long as they were shown as being specifically issued for the assault.
- Operation Delta Force: In the final shootout, one of the main villains, Praetorian, tried making his escape carrying a sample of the Ebola viral antidote, and the Delta team are unable to gun him down for concerns about accidentally damaging the antidote's container. Cue Captain Lang grabbing a nearby firehose, turning it to full blast, and using the impact to knock Praetorian off his feet and subduing the villain long enough for the antidote's retrieval.
- Played for laughs in UHF; when a kid finds a marble in a sandbox filled with oatmeal, he wins the prize of drinking from the firehose, which blows him across the room.
- In A View to a Kill, James Bond knocks the police chief over by opening a valve on the fire engine, blasting him with a high-pressure jet of water; allowing him and Stacy to escape in the confusion.
- MacGyver (1985):
- In "Last Stand", Mac uses the hose on the fire truck to knock a bad guy off of a motorcycle.
- In "Deathlock", Mac uses a high pressure water outlet as a water cannon to push Quayle against overloaded fuse box to electrocute and stun him, before finishing him off with a punch.
- In "Tough Boys", Mac weaves a fire hose through the rungs of a ladder, which enables him to aim the hose at the roof of building before turning on the hose and blasting the thug on the roof.
- Disaster Report: In the level in the Lincoln Plaza, you come across a fire hose. At first, you use one that's on the ground floor - and it's incredibly powerful. How much? Well, it's so strong that it destroy debris like it was nothing. Better yet, you eventually use it to take down the only boss in this game - a helicopter containing the Bazooka Goon, by either "shooting" at an elevator lift or suspended pillars that resemble a chandelier. Either one will send it crashing and exploding. Read that again: you take down a helicopter with a fire hose.
- Disney's Magical Quest: In the first game, one of the outfits Mickey or Minnie obtains is a firefighter outfit, which uses the hose as a weapon, along with the utility of pushing blocks into better positions.