I'd suggest the problem is with routers assuming that a missing access tag should be interpreted as access=yes.
If a common understanding was reached that a missing access tag on a highway=track is *assumed* to imply access=no until proven otherwise, then it seems the problem goes away? When armchair mapping, I don't want to have to tag access=private, fixme="access to be checked" just for the router to have that behaviour. Cheers, JoeG On Thu, 19 Aug 2021, 9:20 pm Little Maps, <[email protected]> wrote: > Hi Andrew, you raised lots points so rather than replying with a complex > embedded messages, I’ve summarised my key thoughts below. I’ve indicated > comments that you made by prefixing them with AH. > > > TL;DR version > > > Tracks are not just for forestry and agriculture, they are for recreation > too, and are definitely seen as public by data consumers. > > > It’s been repeatedly stated on this forum that public access on private > roads is a huge social problem. Hence, roads on private land (tracks, > service, etc) should not knowingly be added to the map unless they carry an > access=private tag. > > > If you ignore everything else below, P-L-E-A-S-E use “access=private” as > the default tag for every driveway/service road/track that is not clearly > on public land. > > > The long version… > > > (1) TL;DR: Tracks are definitely seen as public roads by many data > consumers. > > > AH: “highway=track are documented as forestry, agricultural or fire > trails, so shouldn't be considered as public roads by data consumers.” > > > This is not the what the wiki says. As well as agriculture and forestry, > the wiki lists “outdoor recreation and similar activities” as key > activities on tracks. Also, it does not state that tracks are not “public > roads”. Instead, tracks are not seen as part of “the general purpose road > network” (ie the roads most 2wd cars drive down). > > > All outdoor apps that I’m aware of (cycling, bushwalking, off-roading etc) > treat tracks as open to the public unless they are tagged otherwise. > > > For example, if you set the routing options in OsmAnd to prefer unpaved > roads, it preferentially selects dirt roads and tracks. If you want to > exclude private roads and tracks you can select an option to avoid private > roads. Komoot and other cycling routers do a similar thing if one selects > gravel bike or mountain bike mode. A key problem in using it in Vic is that > it often sends users down roads that are obviously private farm roads (when > viewed on a sat image) but which haven’t been tagged as such. I actually > use it as a tool to find private farm roads (driveways, tracks etc) so I > can add an access=private tag to them so that other users don’t get sent > down them ever again. > > > (2) TL;DR version: Roads on private land (tracks, service, etc) should not > knowingly be added to the map unless they carry an access=private tag. > > > AH: “Do you suggest that maybe tracks on private land shouldn't be mapped > at all or are you suggesting that they shouldn't be mapped without any > access tags set?” > > > Happy to see private tracks on the map if - and only if - they are tagged > access=private. Otherwise I see them as a cancer. > > > Over and over again in the last year or two, this forum has repeatedly > lamented the problems of having private roads marked as open access, > including issues like biosecurity, conflict with landowners, safety, fire > hazards, etc. I can’t think of a topic has been mentioned as often apart > than copyright breaches. Neville circulated a newspaper article on the > problem in Google maps just a month ago. There is no benefit to anyone to > be routed up a road that isn’t open to the public. All it does is make OSM > unreliable and unsafe. > > > IMO, the key problem with the Aus road network in OSM (except perhaps in > Qld and N Aus) is not that it has too few roads, but that it has too many. > We already have a big problem in Victoria with heaps of “paper roads” and > private roads that are tagged as open and public. It’ll take years to > remove those we already have. I dread to think that 1000s of new ones will > continue to be drip fed onto the map from a Map Roulette challenge. > > > AH: “If we add the access tag from Vicmap, then in my view that becomes > more like an import and less like armchair mapping which this quest is > geared towards? So we need to decide if we err on the side of caution, omit > the tag and let on the ground surveys fill in those details or blindly > trust Vicmap access restrictions.” > > > It may seem crude but, given the immense size of these datasets, I > actually view this “soft launch” as you call it, as a “TIGER import by > stealth”. 😉 yeah, I know it’s not a formal import but if an organised > mapping team took up the challenge and added 200,000 roads without > including suitable access tags, local mappers will be cursing this > initiative for decades. > > > I can’t believe that you think you are erring on the side of caution by > omitting suggested government access data. In what way can this be a > prudent approach? Even if 10% are wrong, the rest are going to be helpful. > Hence in contrast to your approach, I suggest “we err on the side of > caution and include the government tag”. > > > So, please add as many tags as possible that indicate likely access and > trust the gov data for now. That’s a better default position than no data. > Perhaps add a note tag saying something like “access data is from Vic gov > and may need to be updated after ground truthing” or the like. > > > [As an aside, your code says that “4: 'motor_vehicle=no', // permanently > closed” but I assume you mean no access to vehicles. This does not forbid > pedestrian access]. > > > AH: “later mappers can follow up with setting access tags once they are > known” > > > Any suggestion that 100-200,000 private roads could be added to OSM and > that problems can be sorted out later is a joke. Who is going to do this? > Every hour spent fixing up errors could be better spent on building the > map. It would take decades to weed about these problems. There aren’t > enough local mappers in rural regions as it is. We don’t want future > mappers to be burdened with the task of fixing tags that could have been > 99% avoided had a couple of lines of code been added initially. > > > So where now? > > > Building on what you’ve already done, my preferred course of action would > be as follows… > > > Filter the Vic and SA datasets using land tenure (public vs private) in > whatever way is practical, and separate both into two separate Challenges, > one titled “Priority challenge: unmapped tracks on public land” and one > titled “unmapped roads on private land” or similar. The filtering may not > be perfect but it should separate most groups reasonably well. > > > The public land dataset will be a great resource and will potentially be > used by many people. The private roads are of less immediate value to data > users (and potentially of negative value if private access is not tagged), > hence the need to keep them separate. > > > Tracks on public land (most of which will be in State Forests and parks) > can be added as is, including any access tags indicated in the gov datasets > plus a caveat note tag on the need to ground check access. The basic > assumption is that access is public unless it is tagged otherwise through > your data wrangling. > > > For all tracks that are not on public land, instead of highway=track, why > not set the default tags as highway=service, access=private (and maybe even > service=driveway) with a note that says something like “private access is > assumed based on mapped land tenure and may prove inappropriate after > ground truthing” or similar. > > > It’s obvious from the Map Roulette map that the majority of the roads on > private land will be short driveways, so highway=service will be a better > default tag than track for most. > > > Again, sorry for the long message. I’ve spent the best part of the last > year working on rural roads, including days of work adding access tags on > private roads. We need to move on from the standard OSM position of “more > is better” to a recognition that, outside of forests and reserves, we have > a great map of public roads in SE Aus. Geometry and tags can always be > improved but we definitely don’t need heaps more roads added to the public > network (which is what effectively happens if private roads don’t have an > access tag). The suggestion that 100s of 1000s of private roads can be > dumped on without adding private access tags will set us backwards, not > forward, by years. > > > > So, if you ignore everything else, P-L-E-A-S-E use “access=private” as the > default tag for every driveway/service road/track that is not clearly on > public land. If in doubt, tag it private and add a caveat note to inform > future mappers how the access tag was derived. Thanks again, Ian > > > _______________________________________________ > Talk-au mailing list > [email protected] > https://lists.openstreetmap.org/listinfo/talk-au >
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