Water cannon

A water cannon is a device that shoots a high-velocity stream of water. Typically, a water cannon can deliver a large volume of water, often over dozens of meters. They are used in firefighting, large vehicle washing, riot control, and mining. Most water cannons fall under the category of a fire monitor.
Firefighting.
Water cannons were first devised for use on fireboats. Extinguishing fires on boats and buildings near the water was much more difficult and dangerous before fireboats were invented. The first fireboat deployed in Los Angeles was commissioned on 1 August 1919. The first fireboat in New York City was "Marine 1", deployed 1 February 1891. There may have been other fireboats elsewhere even earlier.
Fire trucks deliver water with much the same force and volume as water cannons, and have even been used in riot control situations, but are rarely referred to as water cannons outside this context.
Riot control.
The first truck-mounted water cannon was used for riot control in Germany in the beginning of the 1930s.
The most modern versions do not expose the operator to the riot, and are controlled remotely from within the vehicle by a joystick. The Austrian-built WaWe 10.000 by Rosenbauer used by German police can carry of water, which can deploy water in all directions via three cannons, all of which are remotely controlled from inside the vehicle by a joystick. The vehicle has two forward cannons with a delivery rate of , and one rear cannon with a delivery rate of 
Water cannons designed for riot control are still made in the United States and the United Kingdom, but most products are exported, particularly to Africa and parts of Asia such as Indonesia.
Safety.
Use of water cannon in riot control contexts can lead to injury or death, with fatalities recorded in Indonesia (in 1996, when the cannon's payload contained ammonia), Zimbabwe (in 2007, when the use of cannons on a peaceful crowd caused panic), Turkey (in 2013, when the payload was laced with "liquid teargas"), Ukraine (in 2014, with the death of activist and businessman Bogdan Kalynyak, reportedly catching pneumonia after being sprayed by a water cannon in freezing temperatures) and South Korea (in 2016, when a 68-year-old farmer died after injuries sustained by a water cannon the previous year).
Water cannons in use during the 1960s, which were generally adapted fire trucks, would knock protesters down and on occasion, tear their clothes.
On 30 September 2010, during a protest demonstration against the Stuttgart 21 project in Germany, a demonstrator was hit in the face by a water cannon. Dietrich Wagner, a retired engineer, suffered damage to his eyelids and retinas, resulting in near-complete loss of his eyesight. Graphic imagery was recorded of the event, sparking a national debate about police brutality and proportionality in the use of state force.
According to a report issued in the United Kingdom, using plastic bullets instead of water cannons was justified because the latter "are inflexible and indiscriminate", although several people had previously been killed or seriously injured by plastic bullets.
Media effect.
The presence of the media at riots has had a significant impact on water cannon use. There is much pressure on police departments to avoid bad publicity, and water cannons often play badly in the press. It is considered that this is a likely reason that they are not used more often in some countries.
Confrontations that took place in the era of the American Civil Rights Movement, where water cannons were used by authorities to disperse crowds of protesting African Americans, has led to the demise of water cannons in the United States.
Alternative payload.
Dye.
In 1997, pink dye was reportedly added to the water used by South Korean and Indonesian police to disperse a riot. The implication is that they might use this mark to make it easier to arrest rioters later. The United Kingdom, which had sold the water cannon to Indonesia, condemned this practice (although the Royal Ulster Constabulary had used a water cannon with purple dye during The Troubles in Northern Ireland) but later approved the sale of further water cannons to them. Most modern water cannons are also capable of adding tear gas to the stream.
Electrified water cannon.
In 2004, Jaycor Tactical Systems was experimenting with additives (salt and additives to reduce the breakup of the stream into droplets) that would allow electricity to be conducted through water. They have demonstrated delivery from a distance of up to twenty feet (6 m), but have not yet tested the device on people.
Although referred to as an electrified water cannon, this experiment involved a water jet much less powerful than a water cannon.
Other types.
Water cannon differ from other similar devices in the volume of water delivered in a given time, the nozzle speed, the pressure that it is delivered at, and to a lesser extent the total volume that can be delivered. They are also generally portable. The method of employment is also important in labeling a device a water cannon. Nevertheless, the distinction between a water cannon and other similar devices is fuzzy. For example:-
Usage.
Water cannon are still in use on a large scale in Chile, Belgium, the Netherlands and other parts of the world.
Australia.
The State of New South Wales in Australia purchased a water cannon in 2007, with a view to using it during an APEC meeting in Sydney that year. It was not used. It was the first purchase of a water cannon in Australia.
Germany.
The annual riots on 1 May in Berlin, the Schanzenfest fair in Hamburg, which regularly ends in riots, or other demonstrations, are usually accompanied by water cannon, which support riot police. German communities use their water cannon in hot summers to water public parks. The most commonly used water cannon in Germany over years was the Wasserwerfer 9000. Since 2019, the only water cannon type used by riot police, which are around 50 units in total, is the .
Hong Kong.
Three truck-mounted water cannon, officially known as 'Specialised Crowd Management Vehicles', were purchased by Hong Kong Police from France in mid-2018, the truck chassis were provided by Mercedes Benz and the water spray devices were also made by German firm Ziegler, three water cannon cost HK$27 million, a sum that was criticised as excessive for the goods. The vehicles were frequently used by police on participants and bystanders during the 2019–20 Hong Kong protests. Blue dye was often added to the water to allow police to identify protesters. Pepper spray solution was also an ingredient.
On 20 October 2019, police used a water cannon to target and shoot a small group of pedestrians standing outside Kowloon Mosque, in Tsim Sha Tsui, using blue-dyed water mixed with a pepper solution. A large number of Hong Kong residents spontaneously went to the scene to clean up, with the whole incident serendipitously resulting in an increased sense of inclusiveness among mainstream society toward Hong Kong's Muslim and other minorities.
Thailand.
During the 2020 Thai protests, on 16 October 2020, the police used water cannon to disperse a peaceful rally in Bangkok. The water contained an irritant that protesters said made their eyes sting.
Turkey.
The Turkish police water cannon TOMA has been used against protestors many times, including the 2013 protests in Turkey, and are often present at protests of all sizes.
United Kingdom.
Until 2014, although manufactured there, there were only six water cannons in the United Kingdom, all held by the Police Service of Northern Ireland. Water cannon use outside Northern Ireland is not approved, and would require the statutory authorisation of Parliament in England, or of the devolved assemblies in Wales and the parliament of Scotland. In June 2014, London's Deputy Mayor for Policing and Crime Stephen Greenhalgh authorised the Metropolitan Police to buy three second-hand water cannons from the German Federal Police. Mayor of London Boris Johnson said that the purchase had been authorised before Parliamentary approval, as the three cannons cost £218,000 to purchase and would require a further £125,000 of work before being deemed suitable for service, as opposed to £870,000 for a single new machine. But after a study of their safety and effectiveness, Home Secretary Theresa May said in Parliament in July 2015 that she had decided not to license them for use. They were sold in November 2018 with the intention that they were to be broken up for spare parts.
United States.
Truck-based water cannon, and fire hoses used as improvised water cannons, were used widely in the United States during the 1960s for both riot control and suppressing peaceful civil rights marches, including the infamous use ordered by Eugene "Bull" Connor in Birmingham, Alabama in 1963. The newsreel footage of police turning water cannons and police dogs on civilians—both student protesters and bystanders alike, including children as young as six—widely viewed as shocking and inappropriate and helped turn public sympathies towards civil rights. Water cannons were used in November 2016 against water protectors at Standing Rock. In August 2020, state senator Floyd Prozanski suggested water cannons be used by police against protesters in Portland.
Mining.
Water cannons are used in hydraulic mining to dislodge rock material or move sediment. In the placer mining of gold or tin, the resulting water-sediment slurry is directed through sluice boxes to remove the gold. It is also used in mining kaolin and coal.
Other meanings.
The term "water cannon" could also refer to:-