Infrastructures
OpenStreetMap community describes the visible parts of several infrastructures around the world. A constantly evolving tagging framework has been built for years for this purpose.
This page is an entry point for many mapping topics in this field and also documents the way the tagging model can be extended in a sustainable way.
Infrastructures often relate to public utilities and services but also can cover private assets visible from public domain.
It is one of wide fields surveyed by the the community, aside natural environment or POI mapping.
Mapping good practices
Infrastructure mapping is done responsibly by mappers in observance of established OpenStreetMap good practices and editing standards like verifiability without exception.
How to map directions depend on the sector you are interesting in. Some guidelines page exist and are referenced in the Covered topics section below.
Local practices do matter and many sectors already document local projects with scope and feature that are important for the local community. Feel free to contact people to get the last updates about their projects and views.
OpenStreetmap community is committed to provide the most applicable platform for its purpose.
However, we are not able to describe everything about infrastructures and mostly focus on visible and verifiable components. It doesn't mean there's nothing beyond OpenStreetMap about a topic that matters for you. It may be more important to add suitable references on OpenStreetMap and make links with another database containing the information you want to merge.
As an open ecosystem we do value links and appropriate references and encourage to not neglect them.
Stay safe in any circumstance
Infrastructures and utilities sometimes involve technical, complex and/or dangerous processes with heat, power, water, heavy mechanics or deadly chemical products.
Most countries enforce rules to protect populations from those risks and prevent people to access some restricted areas for good reasons.
Although OpenStreetMap contribution is based upon survey, this involvement never requires to put yourself at risk or trespass anything.
Available tagging and encouragement to get many information is always limited by ability to access and obtain them in your own position.
So please, prefer using aerial imagery from home instead of trying to see the label you couldn't behind a fence.
Tagging
OpenStreetMap tagging is expending, refined and adapted to local contexts. As a continuous improvement, established practices may not be enforced equally for every topic or in every location.
As a mostly volunteering work, we prioritize tasks and it's not too late to get involved and help to continue this effort in your surroundings.
Common pattern
Although each field has developed its own tagging along time, we can observe a common pattern and wish to document it for sake of convergence and return on experience.
Containers and contained features
It often starts with containers like buildings, cabinets, stalls or poles that anyone can notice on ground. They've got particular shapes, colours or signs that allow to recognize them and use the according value of man_made=* or building=* in regard of that.
This stage doesn't require more particular tagging and values are intended to be self explanatory for many mappers.
Furthermore, fewer mappers may be knowledgeable about specific features or roles in a given field. OpenStreetMap then provides other keys like power=* or railway=* with more specific focus to describe the functional role of a given container or what is expected to be contained in what we see on ground.
This is likely to be deduced from signage, colours or suitable data for OpenStreetMap and remains verifiable by anyone.
OpenStreetMap practice doesn't force to create separate features for containers and contained objects. They are often merged for sake of simplicity and different tags may come from different mappers.
However, sometimes several different facilities may be contained in the same building. In this case as many different nodes or polygons should be included in the building (don't cut the building), like recommended for telecommunications offices.
Facilities and devices
This is another important distinction made and it's often a particular case for containers / contained features. A facility may contain a set of devices in its premises.
A facility is a place designed and built to host particular activities or processes but won't do anything on itself (a factory is not producing anything, only machines inside are). They are often described as perimeters like a building=* or barrier=*. It is recommended to complete them with utility=* if suitable.
On the opposite, a device is often designed and brought in a facility for a particular function in a more or less complex process. They are often designed as nodes inside facilities perimeters.
Domain keys are not dedicated for facilities or devices. Only values should be focused on one or the another, like power=substation that contains power=transformer.
As mentioned, OpenStreetMap doesn't force to separate facilities from devices and they could be merged as to not clutter the map with unnecessary amount of details.
At least it's easy to separate a facility from its devices by using polygons containing nodes for sake of One_feature,_one_OSM_element but it should be done responsibly depending on the domain's or local practices (see below).
Lines / edges
Infrastructures are often a matter of networks connecting facilities or locations. OpenStreetMap has got corresponding tagging for edges making these connections. It can be roads, pipelines, power lines...
These are mostly described with topic specific keys like highway=primary, power=line with their own properties.
Similarly to container / contained paradigm for punctual features, it's sometimes necessary to include such an edge into a surrounding tunnel or bridge to let them pass an obstacle.
Or some topics may already have implemented a more concrete nested model like tunnel=yes + man_made=pipeline + waterway=pressurised for a waterway inside a pipeline inside a tunnel.
Logical connections
Once physical edges are described in the database, we have got many opportunities to keep track of logical connections between facilities where relevant. Such connections are mostly mapped with relations in OpenStreetMap and obtained by observation or indications from ground.
They translate a functional perspective over the physical infrastructure. It includes bus lines over road network or power=circuit over power grid.
In practice it allows to reduce the amount of geometry needed. We can involve a single way segment in as many relation as needed without duplication.
It is the most refined content used to be map on OpenStreetMap.
As an abstracted layout over physical reality, we only use this to represent relations that are observable on ground. You can usually inspect a road to get which buses run over it or a power line to see which substations it connects.
On the opposite, we don't represent relations we can't survey, like telecommunications circuits or aerial routes.
Markers
Markers are important indications as visible objects and sometimes landmarks. They indicate the presence of some hidden stuff nearby without being directly supported by or physically linked to them.
We can sometimes use them to deduct the path something follows, associated with other hints or marks on the ground. The markers have to be permanent to remain verifiable by anyone.
We are using marker=*, indication:*=* and utility=* to describe them.
Improve this tagging
Improve tagging is a never ending activity in OpenStreetMap and you may be interested in a sustainable methodology focused on infrastructure to preserve the common pattern described upside. Here is some advice:
The semantic spread between containers and contained features looks to increase along refinements. As a sane practice, we could encourage this for the sake of:
- Keeping the complexity away from most used keys in the project like
man_made=*,amenity=*orbuilding=*. Using them for basic topics like buildings or urban furniture is fine and established. - Provide consistent keys and values for each field with their own roadmap and lifecycle without conflicts between each others.
As a consequence, always think twice about adding new values to generic keys like man_made=* and consider some more focused keys like railway=* to propose new tagging for some missing feature.
Secondly, preserving the necessity of distinction between facilities and devices will save us from consistency issues in the future and is also important.
Finally, some existing tagging from another sector may be suitable for your own need. It is often useful to take a wider look of neighboring sectors to get inspired by existing practices instead of creating another one.
In this perspective, tagging improvement should seek for the most generic solutions as possible and as specific as necessary.
For instance, it was more versatile to define handle=* to be suitable for both doors and valves with appropriate values instead of introducing specific door:handle=* and valve:handle=*.
Writing a proposal along the Proposal_process may be useful to keep track of corresponding discussion about an important topic. As infrastructures topics may be complex, the community may appreciate a proper documented proposal prior to review the opportunity of it.
The importance of references
External references
Wikidata
Wikidata helps us a lot to aggregate knowledge about specific items and provide stability about variable information along time.
Any significant infrastructure can be linked to the corresponding Wikidata item with wikidata=*.
Some attributes with less robust or often changing values may be more beneficial to OpenStreetMap when populated with the stable Wikidata ID.
Those QIds preserve a link that would be destroyed each time a name or a reference changes.
It is particularly useful for operator=* or owner=*, respectively completed with operator:wikidata=* or owner:wikidata=*.
Covered topics
Always refer to global page Mapping features to get a list of what is commonly used in OpenStreetMap.
This list can be completed wit any topic related to infrastructures if something's missing.
Roads
Road domain is addressed with highway=*.
Water
Water field is very vast and has got several keys, like waterway=*.
See water management or Waterways pages to get more information.
Railway
Railway sector is addressed with railway=*.
Power
Power (electricity) domain is addressed with power=*.
Dedicated pages about power networks or power generation are available to inventor local projects.
You may also find particular guidelines for most common components for power networks and power generation.
Heating
Oil and gas
Telecommunications
Telecommunications domain is addressed with telecom=*.
You may find more information on the telecom page.
See also