Should I map sidewalks? If yes - how? Using highway=footway?
Pros: adding valuable data for pedestrian routing
Cons: adding very large amount of data to OSM, every street usually have 2 sidewalks (on each side), greatly increasing increasing number of junctions (between streets and sidewalks). The rendered tiles could look messy and overcrowded.
If there is a place with tagged sidewalks, could you provide a link to it so I could see how it is done?
asked 20 Oct '10, 06:34
You should avoid tagging them in a way that makes them indistinguishable from footways that are independent from roads. As long as you make sure that they are identifiable as sidewalks, it's the renderer's choice whether or not to display them. So if you are interested in mapping sidewalks, start mapping them.
As for how to map sidewalks, there is no clearly preferred solution. The two primary alternatives are:
Valid arguments exist for both alternatives: Adding tags to a sidewalk is much easier with separate ways, and detailed information about crossings and junction layouts can barely or not at all be mapped with tags. Some feel, however, that separate geometry is redundant and makes some common operations (e.g. moving the road) more laborious. Separate geometry can also make certain rendering styles much harder to produce without overlaps or other, often zoom-dependent visual problems.
There are several proposals for more complex tagging, too, usually based on relations. While far less frequently used, these will often allow you to model not only sidewalks, but the entire structure of the road - including lanes for motorized traffic and dividers - with a very high level of detail. The area relation proposal is an example for this.
This issue will likely not be resolved soon, at least unless support for one of the solutions becomes more widespread in applications.
I know this is an old discussion, but still wanted to add the fact that there is now an approved tag for mapping sidewalks:
With the new Bing maps backgrounds, tracing sidewalks has become a whole lot easier. I definitely think that this is not something that should be discouraged, since it could potentially make OSM the prime source of routing for wheelchair users and blind persons. Sure, in the near future it will be limited to urban areas, but that is also where potential use would be the greatest.
And, as mentioned earlier in the thread, if mapping separate sidewalks is undesired for whatever reason, using tags on the nearby street is also possible and does not have to be seen as mutually exclusive to mapping separate ways for sidewalks. Note that, at the time of writing, the tag to use for this is still only a proposal:
Finally, here's a sidewalk "landing page" from the wiki, explaining the current status:
As for the argument that the map will get cluttered, imho that is something that should be solved by adjusting the rendering.
answered 29 May '11, 23:36
Are you mapping in a town or city where sidewalks/pavements are ubiquitous or in a rural area where they aren't? If the former, then sidewalks/pavements could arguably be described as "lower priority" items - people are going to assume that they're there and mapping them (either as separate ways or as tags against the road) doesn't necessarily add information.
Personally, I'm mapping in semi-rural areas and the existence of a sidewalk/pavement is one of the most important foot routing criteria, so I do try to add them. I tend to add them as tags rather than separate ways, because it's less effort to do that, but if your locality has a foot/cycle infrastructure that is largely distinct from roads than separate ways would make more sense.
answered 08 May '11, 23:32
A lot of people make the comment that in urban/residential areas sidewalks always exist.
I'd have to say this is very country dependent. Here in Korea, more often than not, only the primary, secondary, and occasional tertiary roads in a city have actual sidewalks. For residential roads, pedestrians and traffic share the same way. Yes, unsafe, but that is how things have developed.
Occasionally if part of the city has a new-ish development it might include sidewalks on residential streets, but then again, maybe not.
So far I haven't really mapped any/many sidewalks and those that I have mapped have been done as separate ways because I feel that the way is needed as it connects to other paths which lead into parks, residential complexes or the like.
This is the first time I have heard of the "highway=footway + footway=sidewalk" scheme.
answered 09 May '11, 11:07
As a compromise, I would only tag sidewalks where their existence or absence is unusual.
There is already a proposal to derive access rights from the road type (http://wiki.openstreetmap.org/wiki/OSM_tags_for_routing/Access-Restrictions ). I would use something similar for sidewalks.
For example: Residential streets almost always have sidewalks, so there I'd only tag if they are missing. On the other hand, trunk roads usually do not have sidewalks, to I'd tag them if they are there.
Of course, for this we'd really need a detailed proposal like the one for access restrictions, but until that is present, I'd generally only tag missing sidewalks for residential roads.
After a whole lot of other detail has been added, mapping them separately is more likely to start making sense. For most areas it's still at least many years in the future. We've done that for about half of the city so far. In the future more accurate positioning systems can make use of the data - think for example navigation for the blind, or wheelchair routing. Without a separate geometry for the sidewalks you also get misleading angles at the places where a sidewalk diverges away from the street to become a separate footway. Adding a single sidewalk of many sidewalks in an area hardly makes sense, se most users will start with tagging the roads footway/sidewalk=both/left/right/none.
answered 26 Oct '10, 08:44
I support the proposals to use tags. Without a way to join ways together, so they move as a unit, adding sidewalks creates far too much clutter. Using tags leverages what we've got in OSM, rather than starting yet another project that's just too big.
It makes a lot of sense to only tag the exceptions - that's something where we could go from no sidewalk data to a routing map for the blind in a short period of time. The problem is, what's the norm for an area? In a rural area you may have tens of thousands of miles with no sidewalks. In an urban area sidewalks are the norm, and all that's interesting are the gaps.
This gets into the issue of default land use for an area. Default speed limits. And default sidewalk condition. With good defaults, we could map the exceptions, and build a useful result soon.
answered 12 Jan '11, 08:49
Bryce C Nesbitt
There is a image of the week about this: lot of footway.
In my mind sidewalks are just an other lane on the street. Street not just limited on asphalted part. So I think sidewalks may be tag like cycleway are. But this is not yet explored. This is my point of view today, need to be tested.
answered 20 Oct '10, 09:27
Honest answer: No. No you should not map sidewalks.
But it is an interesting question. There's no limit to the amount of detail you can add to openstreetmap. You could add a millions of nodes in the park with
We had a discussion about this kind of thing over on Tom Chance's blog recently. Sidewalks ('pavements') were an example I gave of a silly level of detail which we have (almost) all decided not to map.
answered 21 Oct '10, 16:09