question on lanes restrictions

iriman · 2018-10-02T13:05:18.000Z

Hi,

There is a two-way street. Two lanes forward, one lane backward. backward is designated for psv (taxi and bus) and is not allowed for general traffic. Are these tags enough to describe this street? Does popular routing apps support it?

highway=tertiary
lanes=3
lanes:backward=1
access:lanes:backward=no
psv:lanes:backward=yes

for better understanding, this is the way https://www.openstreetmap.org/way/326864102. and this is osm data before I change it: sheykh_fazlollah_before

There are more streets in my city like this and they are mapped using two osm-ways, while are not physically separated.

thanks

hadw · 2018-10-02T13:34:02.000Z

I think I would want oneway=yes. I’m not sure how you cancel that out for the PSVs. I can see why it might have been mapped as two parallel ways.

Are you subject to US type Jay Walking laws? The main disadvantage I see with mapping it as two ways is that routers are less likely to consider it crossable by foot outside of official crossing, but if doing so is illegal in your country that might not matter.

iriman · 2018-10-02T14:37:31.000Z

I had no idea how use oneway=yes. as is, or with lanes suffix: oneway:lanes=yes|yes|yes. I’m in doubt if routing apps know these tags.

I’m not much aware of that law. Anyone can cross the street at any point in city streets, but if there is a designated crossing for pedestrians and someone crosses from somewhere else, in case of accident, pedestrian has done an illegal act.

iriman · 2018-10-02T18:41:24.000Z

Maybe I had a misunderstanding here.:rolleyes: I was thinking about lanes as separate ways and was trying to behave with them like oneway ways (oneway:lanes=yes|yes|yes). I looked on some ways with similar tags , e.g. this one and found out it could be tagged as this:

highway=tertiary
lanes=3
lanes:backward=1
psv:lanes:backward=yes
oneway=yes - what it means: make all lanes oneway in direction of osm-way (?)
oneway:psv:no - what it means: for PSVs whole of the way is not oneway and they can drive backward only in the backward lane specified above (?) and drive forward only in those two forward lanes like general traffic (?)

what do you think about this way of tagging and my understandings?

n76 · 2018-10-03T15:19:41.000Z

From my reading of the access [1] and lanes [2] pages on the wiki, I think I’d tag it as:

 
highway=tertiary
lanes=3
lanes:backward=1
lanes:forward=2
access:lanes:backward=no
psv:lanes:backward=designated

I would not use the

oneway=yes

tag as it seems to mean all lanes and editors and validators could flag it. At least I’ve seen JOSM complain when a

lanes:backward:*=*

tag is found on a way with

oneway=yes

.

[1] https://wiki.openstreetmap.org/wiki/Lanes#Examples
[2] https://wiki.openstreetmap.org/wiki/Key:access#Lane_dependent_restrictions

hadw · 2018-10-03T15:26:31.000Z

The reason I would want to tag oneway is that there is a general principle that you start with the most common case and then qualify it.

That way, simpler data consumers will get an answer that is right most of the time, and, in particular, right for the people who are least likely to know the answer.

Validation errors should only be used as hints, and should always be validated by humans.

Rightly or wrongly, cycle users are seen as secondary users, for most purposes, so one would expect one way tagging for the road, and then cycle specific tags to cancel that for cycles, when there is a contraflow lane for cyclists. Similarly for PSVs.

n76 · 2018-10-03T17:10:26.000Z

To the first approximation it is a two way street, it is just that traffic in one direction is restricted. . .