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

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