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Public-images-osm logo.svg emergency = fire_hydrant
Downtown Charlottesville fire hydrant.jpg
An active fire protection measure, and a source of water provided in most urban, suburban and rural areas with municipal water service to enable firefighters to tap into the municipal water supply to assist in extinguishing a fire. Edit or translate this description.
Group: Emergency
Used on these elements
may be used on nodesshould not be used on waysshould not be used on areasshould not be used on relations
Useful combination
Status: approvedPage for proposal

Fire hydrant definition

A fire hydrant (also known colloquially as a fire plug in the United States or as a johnny pump in New York City) in OSM is defined as a device to take water for firefightening purposes and it can be pressurized or not.

Suction point definition

On the other hand, a suction point in OSM can be intended as a place where to park the fire engine to easily take water with your pump from a river, pond, lake...

Use emergency=suction_point for this points, but refer to Suction point wiki page.

How to map

For numeric values with units, see the guidelines: Map Features/Units

Basic tags

Basic tags
Tag Description Valid values
Tag a Node with this tag to identify the location of a fire hydrant.
fire_hydrant:type=* The shape of the hydrant. See the table below for details. pipe, pillar, wall, underground
fire_hydrant:pressure=* Pressure at which the water is supposed to flow through the hydrant.

If in pressure but you don't know the value use fire_hydrant:pressure=yes.

If the hydrant is connected to a pond/stream/tank/pool and a pump is needed to get water, use fire_hydrant:pressure=suction.

If this tag is is not specified, pressure is assumed to be unknown.

# (numeric value) in bar/yes/suction

fire_hydrant:type=* details

Values for fire_hydrant:type=*
Value Description
pipe An hydrant consisting of a simple capped pipe, without the usual hydrant shape.
Hydrants 20130326 112938.JPG
pillar A pillar type hydrant. If you want to be more specific, see pillar:type=* below.
Downtown Charlottesville fire hydrant 1.jpg
wall A wall-mounted fire hydrant.
Guentherscheid Tunnel Rescue4.jpg
underground A fire hydrant simple outlet located underground, underneath a metal cap. Hard to know anything about couplings, whench or sizes without opening the cap.

It is necessary to carefully look on the cap. There are other types of objects hidden below similar caps in some places like measuring points (e.g. labelled "GWM") or natural gas (labelled "Gas"). Hydrants are of course labelled "HYDRANT".

In Austria and Germany underground hydrants are of the same type. Inside there is not a normal coupling, but a bayonet coupling where the standpipe is locked in. The coupling should be Bayonet 70 mm all over the two countries.

Berlin hydrant 20050211 p1000517.jpg

Optional tags

All other tags are optional but are useful for firefighting purposes. If you don't know the data, simply don't use these tags.

Optional tags
Tag Description Valid values Examples
fire_hydrant:diameter=* This is the nominal diameter of the underground pipe going along the street that feeds (among other things) the hydrant. In some countries you can read it on the signboard near the hydrant: generally it is the number on the top of the sign.

NB: Do not confuse the number printed on the sign with the number that is printed on the hydrant, that instead is generally the diameter of the flanged connection between the hydrant and the underground pipe. This diameter currently is NOT tagged.

# (numeric value) in mm, inches or letters.
In Belgium, the number on the top of the sign is the nominal diameter in mm of the underground pipe that feeds the hydrant. Other numbers are the distances in meters of the hydrant from the sign (on the left / on the right / frontally).
flow_rate=* Nominal flow rate. If fire_hydrant:awwa_class=* is present, this tag is redundant. # (numeric value) with unit of measure, in International System standard unit is m3/s. But for hydrants are preferable l/min (liters per minute), usgal/min (US gallons per minute), ukgal/min (UK gallons per minute), or m3/h (cubic meters per hour). e.g.: flow_rate=600 l/min.

In France, a normalized fire hydrant needs to supply 120 m3 during two hours. In the US, this specification is in Gallons Per Minute.

The use of usgal/min or ukgal/min instead of gpm is necessary because UK and US gallons are different.

fire_hydrant:awwa_class=* In the US, classification per American Waterworks Association. If flow_rate=* is present, this tag is redundant. See tha table below for details. AA, A, B, C
couplings=* Number of couplings. # (numeric value)
couplings:type=* Coupling standard. Bayonet, Barcelona, Guillemin, Klaue, Sprawny, Storz, UNI

More types are described at: https://en.wikipedia.org/wiki/Hose_coupling

couplings:diameters=* Each coupling diameter, separated by semicolons. #;#;# (numeric values). Always specify the unit of measure, normally use mm. For inches use ". In some countries characters A, B, C are used to specify the connector (Austria and Germany)

e.g.: taken this image & guessing diameters, this could result in: couplings:diameters=45 mm;45 mm;110 mm

pillar:type=* For better description of pillar hydrants, in addition to fire_hydrant=pillar. See below for details. dry_barrel, wet_barrel
water_source=* The water source for the hydrant. main, stream, river, canal, drain, ditch, pond, lake, water_tank, swimming_pool, groundwater, ...

"main" means a hydrant connected to a pipe which is fed by the local distribution network.

"groundwater" is for water wells.

This list may not be exhaustive. As a rule of thumb the value of water_source=* should repeat the tag of the related water source, if present (e.g. if the hydrant takes water from a source that is tagged as waterway=river then water_source=river, and so on).

water_volume=* Volume of the water reserve, applicable only to water tanks and swimming pools. # (numeric value) in m3. If another unit of measure is used, specify it
survey:date=* Date of the last site survey (this tag is not specific to fire hydrants). This means that someone observed the hydrant at this location on this date. This does not imply that a functional check was done at that time.

For the date of last functional check, another tag (not yet defined) will be necessary.

colour=* The colour of the hydrant. Unless otherwise specified, the entire hydrant is this colour. blue, green, yellow and red are the valid values in the AWWA scheme, but many jurisdictions do other things
bonnet:colour=* Colour of the top section ("bonnet") of the fire hydrant if different from the colour tag value. blue, green, yellow and red are the valid values in the AWWA scheme, but many jurisdictions do other things
cap:colour=* Colour of the caps of the fire hydrant if different from the colour tag value. The caps are the covers over the hose openings. blue, green, yellow and red are the valid values in the AWWA scheme, but many jurisdictions do other things. If caps are painted in more than one colour, list all colours separated by semicolons
reflective:colour=* Colour of reflective material, if any (commonly stripes or bands around the barrel).
disused:emergency=fire_hydrant Hydrants are supposed to be in service by default. On the contrary, if the hydrant is out of service, use this tag.
manufacturer=* To retreive information from manufacturers' documentation (this tag is not specific to fire hydrants).
model=* To retreive information from manufacturers' documentation (this tag is not specific to fire hydrants).
fire_hydrant:position=* Description of the position lane (on the side of a road lane), parking_lot (in a parking), sidewalk (on a sidewalk), green (in a grassy area)
fire_hydrant:count=* Number of hydrants, if there are more than one. Anyway it would be preferable to tag each hydrant with its own node (according the policy "one feature = one node"). # (numeric value)
fire_hydrant:style=* For special designs. wsh, ...
ref=* Reference number, if applicable. # (numeric value)
name=* Name, if applicable.
fire_hydrant:opening=* Direction to open the valve. Indicated in the corner of the signage in Hungary with a round arrow. cw (clockwise), ccw (counterclockwise)

fire:hydrant:awwa_class=* details
American Water Works Association colour scheme

Wet Hydrants are generally fed by water mains in urban and suburban areas. The dimensions of the mains vary greatly, and so the flow capacity of the hydrants can vary substantially. The location of hydrants is the first requirement in a mutual assistance call; the second most important piece of information is the flow capacity. Some jurisdictions in the United States have adapted a colour scheme specified by the American Water Works Association. In these jurisdictions, flow capacity may be determined simply by examining the colour of the bonnet and caps of a fire hydrant. In other cases, finding out the capacity may be more difficult.

Flow Capacities and AWWA Colour Scheme
Class Flow Capacity Bonnet & Caps Colour
AA more than 1500 US gal/min Light blue
A between 1500 and 1000 US gal/min Green
B between 1000 and 500 US gal/min Yellow
C less than 500 US gal/min Red

pillar:type=* details

Values for pillar:type=*
Value Description
dry_barrel A style of pillar hydrant where the water shutoff valve is below ground, hopefully below the frost line. These are used on pressurized systems where freezing is a risk. They are occasionally used for dry hydrants when the water supply is higher in altitude than the hydrant.

The type may be determined by inspecting the caps: they are usually arrayed at the same level as there is no corresponding valve inside the hydrant barrel. The handle to operate the underground valve is ususally on the top (bonnet) of the hydrant.

Bethlehem 20130426 102052.JPG
wet_barrel A style of pillar hydrant where the barrel is pressurized at all times, with individual valves for each outlet. These are common in temperate climates, but not used wherever the temperatures may be consistently below freezing.

The type may be determined by inspecting the caps: each cap has a valve internal to the hydrant barrel and the handle to operate it is usually opposite to the corresponding cap. The caps usually are not arrayed on the same level, but this peculiarity, if alone, is not enough to identify a wet barrel hydrant.

Fire hydrant in Bonifacio Global City.jpg

Deprecated tags

This because "pond" is the water supply, not the physical delivery mechanism (like underground/pillar/wall).
This because the prefix disused: is already used in other contexts and indicates the same concept.
This because a generic tag for flow rate can be useful for many other features (man_made=pipeline, waterway=river, waterway=canal, waterway=stream, waterway=brook, waterway=drain, waterway=ditch).
This because it was not immediately clear to which standard this class refers to.
This because a generic tag for water source can be useful for other features (emergency=suction_point and virtually others).

How to find an underground fire hydrant: signage

Possible rendering

Emergency fire hydrant.svg suggested by User:Chrisana13


  • Karta01 shows all fire stations, rescue stations and hydrants in Belarus, Kazakhstan, Russia and Ukraine
  • OpenFireMap shows all fire stations and hydrants, see OpenFireMap in wiki
  • OsmHydrant Tool for displaying, creating & editing hydrants, see OsmHydrant in wiki

See also