This raises the question: how did the surface=gravel tag end up getting defined as large aggregate/railway ballast anyway, given it appears at odds with almost everyone’s usage of it, including other significant online references such as: https://en.wikipedia.org/wiki/Gravel_road (which matches the vernacular perfectly)?? Any OSM old-timers recall enough to comment? Is there actually anywhere in the world where roads are commonly done this way?
With regard to: > Hi Josh and co, I ride a “gravel bike” on dirt roads that are signposted as > “gravel road”but definitely don’t fit the OSM definition of gravel = railway > ballast. and Michael’s > I don't map much in the US but do in Australia and Sweden. In both countries, > I have rarely come across what I consider to be gravel roads, instead > consider most unpaved roads and tracks to be 'dirt' or 'compacted': Same here. I might provide a single counter-example; the major through road in the Watagans near me was actually lined with this large ballast last time I rode through; an absolute nightmare to ride on, and I can’t imagine it’s too kind on vehicles either. Presumably an initial step before further surfacing? Has anyone else seen this surface? > On 23 Feb 2021, at 8:44 pm, Little Maps <[email protected]> wrote: > > Hi Josh and co, I ride a “gravel bike” on dirt roads that are signposted as > “gravel road”but definitely don’t fit the OSM definition of gravel = railway > ballast. Because of the common usage of gravel as a variably textured dirt > road in Australia, we face a massive uphill battle to get accurate, specific > unpaved road surfaces in OSM. Here’s some data from Overpass Turbo queries of > all unpaved highway surfaces in Victoria. This includes all highway tags (inc > roads and paths) not just tracks: > > Surface Number Percent > unpaved 48664 80 > gravel 6159 10 > dirt 4559 8 > compacted 642 1.1 > sand 406 1 > fine_gravel 230 0.4 > earth 46 0 > Total 60706 100 > > In case that’s illegible, if you add all of these unpaved/dirt/gravel ways, > 80% are tagged with a generic unpaved tag (which is entirely accurate if not > especially precise). Gravel is the next most common category, accounting for > 10% of ways. Apart from dirt at 8%, the rest are used very rarely. > > My guess from tagging surfaces on a lot of unpaved roads is that perhaps 80% > of the roads tagged as gravel do not satisfy the OSM wiki definition and > should be tagged as something else. Interestingly, the two most relevant tags > for formed, unpaved surfaces - compacted and fine_gravel - are very rarely > used (around 1% each). There are probably more ways that have fence-sitting > tags like “dirt; sand; gravel” that end up being pretty meaningless. > > Adding precise surface tags may be simple on roads that are freshly > maintained but on roads that haven’t been maintained for a while they’re > often pretty difficult to assess anyway. > > Personally, I feel that there’s often too much emphasis in OSM on precision > (i.e. use detailed sub-tags) at the expense of accuracy. I believe most of > the generic unpaved tags are accurate. I wish I could, but unfortunately I > don’t believe many of the specific sub-tags are especially useful. (Sand is a > goody though!). Cheers Ian > >> On 23 Feb 2021, at 5:22 pm, Josh Marshall <[email protected]> wrote: >> >> >> The approved OSM tag for surface=gravel >> <https://wiki.openstreetmap.org/wiki/Key:surface> refers to railway ballast, >> not the fine crushed rock or natural surface that usually occurs on unpaved >> roads in Australia. However we call the fine unpaved surface "gravel" in >> common parlance, and many unpaved roads that don't constitute gravel as >> described in the OSM wiki have been tagged as gravel here, erroneously >> depending on your point of view. >> >> This is a matter of interest to me too. I spend a substantial amount of time >> running+riding on fire trails in NSW (all highway=track), and the surface >> type is useful and indeed used in a number of the route planners I use. I >> have changed a few roads back to 'unpaved' from 'gravel' due to the rule of >> following the description in the surface= guidelines rather than the name. >> >> My question then however, is exactly what to tag the tracks beyond "unpaved". >> >> There are definitely sections that are somewhat regularly graded and appear >> to have extra aggregate/fine gravel added. From the surface= wiki, these >> most closely align with surface=compacted. But fine_gravel is potentially an >> option too. Many of these are 2wd accessible when it is dry. (Typically >> smoothness=bad.) >> >> There are also others, usually less travelled, which are bare rock, clay, >> dirt, sand, whatever was there. Is it best just to leave these as >> surface=unpaved, and add a smoothness=very_bad or horrible tag? None of the >> surface= tags really seem to apply. >> >> >> On Tue, 23 Feb 2021 at 16:45, Little Maps <[email protected] >> <mailto:[email protected]>> wrote: >> Hi Brian and co, in Victoria and southern NSW where I've edited a lot of >> roads, highway=track is nearly totally confined to dirt roads in forested >> areas, as described in the Aus tagging guidelines, viz: " highway=track >> Gravel fire trails, forest drives, 4WD trails and similar roads. Gravel >> roads connecting towns etc. should be tagged as appropriate (secondary, >> tertiary or unclassified), along with the surface=unpaved or more specific >> surface=* tag." >> >> In your US-chat someone wrote, "...in the USA, "most" roads that "most" >> people encounter (around here, in my experience, YMMV...) are surface=paved. >> Gravel or dirt roads are certainly found, but they are less and less >> common." By contrast, in regional Australia, most small roads are >> unpaved/dirt/gravel. >> >> In SE Australia, public roads in agricultural areas that are >> unpaved/dirt/gravel/etc are usually tagged as highway=unclassified (or >> tertiary etc), not highway=track. There are some exceptions in some small >> regions (for example in the Rutherglen area in NE Victoria) where really >> poor, rough 'double track' tracks on public road easements have >> systematically been tagged with highway=track rather than >> highway=unclassified. See here for example: >> https://www.openstreetmap.org/#map=13/-36.1424/146.3683 >> <https://www.openstreetmap.org/#map=13/-36.1424/146.3683>. However, this is >> not the norm in SE Australia and across the border in southern NSW, this >> type of road is nearly always tagged as unclassified, as it is elsewhere in >> Victoria. In SE Australia, my experience is that tracks are tagged in the >> more traditional way, and not as has been done in the USA. >> >> If I could ask you a related question, what do you US mappers call "gravel"? >> The approved OSM tag for surface=gravel >> <https://wiki.openstreetmap.org/wiki/Key:surface> refers to railway ballast, >> not the fine crushed rock or natural surface that usually occurs on unpaved >> roads in Australia. However we call the fine unpaved surface "gravel" in >> common parlance, and many unpaved roads that don't constitute gravel as >> described in the OSM wiki have been tagged as gravel here, erroneously >> depending on your point of view. How do you use the surface=gravel tag in >> the USA? Cheers Ian >> >> On Tue, Feb 23, 2021 at 2:49 PM Brian M. Sperlongano <[email protected] >> <mailto:[email protected]>> wrote: >> Hello all, >> >> Recently, there was a discussion on the talk-us list regarding how we use >> the tag highway=track. That discussion begins here: >> https://lists.openstreetmap.org/pipermail/talk-us/2021-February/020878.html >> <https://lists.openstreetmap.org/pipermail/talk-us/2021-February/020878.html> >> >> During that discussion, someone suggested that Australian mappers may also >> be using the highway=track tag in a similar way to US mappers. Hence this >> message :) >> >> I've recently made edits to the wiki page for highway=track describing how >> the tag is used in the USA: >> >> https://wiki.openstreetmap.org/wiki/Tag:highway%3Dtrack#Usage_in_the_United_States >> >> <https://wiki.openstreetmap.org/wiki/Tag:highway%3Dtrack#Usage_in_the_United_States> >> >> If there is similarly a local variation in how this tag is used, I would >> encourage the Australian community to document their usage as well. >> >> Brian Sperlongano >> Rhode Island, USA >> _______________________________________________ >> Talk-au mailing list >> [email protected] <mailto:[email protected]> >> https://lists.openstreetmap.org/listinfo/talk-au >> <https://lists.openstreetmap.org/listinfo/talk-au> >> _______________________________________________ >> Talk-au mailing list >> [email protected] <mailto:[email protected]> >> https://lists.openstreetmap.org/listinfo/talk-au >> <https://lists.openstreetmap.org/listinfo/talk-au>
_______________________________________________ Talk-au mailing list [email protected] https://lists.openstreetmap.org/listinfo/talk-au
