Correct way to split ways at 4-road intersection for right turns?

PhilCJ · 2017-12-19T21:38:32.000Z

I’ve looked that the tags of the simple and JOSM editors and cannot find anything that looks like dual carriageway, i.e. a road with directions physically separated. Can you pretty please point me in the right direction?

Thanks

PhilCJ

n76 · 2017-12-20T03:36:00.000Z

PhilCJ:

I’ve looked that the tags of the simple and JOSM editors and cannot find anything that looks like dual carriageway, i.e. a road with directions physically separated. Can you pretty please point me in the right direction?

Thanks

PhilCJ

A dual carriageway is not done with tagging alone: You draw two separate carriageways and add oneway=yes tags to each.

When I do this, I usually look at the direction arrows by each node in the existing way and see which way it was drawn. I then move that way to be aligned with the appropriate direction and add the oneway tag. Then I draw the other way where it should be. Finally, I copy all the tags from the original way (including the newly added oneway=yes tag) and paste them onto the new way. That whole operation is much easier if you are dealing with a single way that has not been split up for things like adding turn lanes, etc., so I usually do the change to dual carriageway prior to doing turn lanes.

escada · 2017-12-20T13:52:18.000Z

The method n76 describe is fine for the simple tags, but there is a potential problem with relations when you “split/duplicate” a way to represent a dual carriageway.

E.g. public transport routes are represented as relations in which the way is a member. JOSM (or one of it’s plugins) has a method to copy relations from one way to another. This would be easy, but you introduce a oneway. This means that half of the relations should contain the way in one direction and the other half have to contain the other direction.

It’s pretty hard to explain in a few words, so I can understand you might be scared by now. Please don’t, do what n76 described and ask for help here on splitting the relations.

hadw · 2017-12-20T14:06:59.000Z

Fortunately, there are no relations currently mapped, but they would have required handling for filter lanes, as well.

Also, I don’t think the filter lane should be considered a secondary road, particular the bit that is part of the residential road. I’d need to think more carefully as to what it should be.

The need for a filter lane at all, or two lanes in each direction, makes me question whether the residential road really is a residential road, or whether it is, maybe, tertiary, or unclassified.

PhilCJ · 2017-12-20T18:46:17.000Z

Thanks n76, escada, and hadw,

Regarding the right turn from Stockton to Elder Creek, which is tagged as secondary. I see this conceptually as 3 entities:
1 - a link from the Stockton Boulevard way
2 - a right turn filter lane
3 - a link to Elder creek Road way

I added a one way attribute and smoothed out the turn. What I wonder is the meaning of “Secondary link”? in JOSM (There are also a primary and tertiary links). Should 1 and 3 above be “links” or unclassified ? Should 2 be unclassified?

Regarding turning 47th street into two ways, it currently has Lane and road attributes which I will remove and follow n76 recommendations then add Lane and road attributes back in, unless I hear differently

Thanks very much

Regards

PhilCJ

PhilCJ · 2017-12-20T20:49:09.000Z

So I split 47th avenue - I don’t know if I did it correctly at the split/merge nodes. I also added Pedestrian Crosswalk to nodes on the two unidirectional ways near the intersection. Before I do the same to Stockton Boulevard north of the junction, would you kindly see how much of a mess I made with 47th Ave and let me know?

PhilCJ · 2017-12-21T15:24:42.000Z

So I went ahead and split Elder creek into a dual carriageway, it looks strange with the Lane and road attributes visible on the way that connects dual carriageway to non-carriageway, is this the correct way to do this?

Also…in the non physically divided section of Elder Creek, there are two lanes in both directions with a middle lane having orange lines. It seems that this is for traffic in both directions so I selected that in the Lane and road attributes and got the error message shown below.

https://www.openstreetmap.org/?mlat=38.51050&mlon=-121.43587#map=19/38.51050/-121.43587

What is the correct way to tag the center lane using Lane and road attributes?

Thanks for your help;)

Regards

PhilCJ

n76 · 2017-12-21T15:54:51.000Z

PhilCJ:

So I went ahead and split Elder creek into a dual carriageway, it looks strange with the Lane and road attributes visible on the way that connects dual carriageway to non-carriageway, is this the correct way to do this?

Also…in the non physically divided section of Elder Creek, there are two lanes in both directions with a middle lane having orange lines. It seems that this is for traffic in both directions so I selected that in the Lane and road attributes and got the error message shown below.

https://i.imgur.com/scOLwbn.jpg

What is the correct way to tag the center lane using Lane and road attributes?

Thanks for your help;)

Regards

PhilCJ

The lanes tagging should be something like:

lanes=5
lanes:forward=2
lanes:backward=2
lanes:both_ways=1

FWIW, the “turnlanes - tagging” plug in for JOSM makes this much easier two work with.

PhilCJ · 2017-12-21T16:33:11.000Z

Hi N76

Yes that is what I did

The error message on the map says Invalid turn:lanes both_ways value

Any ideas?

Regards

PhilCJ

n76 · 2017-12-21T17:31:43.000Z

Thank you for posting a link of the area. It allowed me to see the satellite imagery without the OSM data so I could figure out how I might tag it from scratch.

It looks to me that the section you have tagged as turn:lanes:both_ways=reversible has the paint striping typical of a “center turn lane” even though it does not have the arrows painted in the middle (I think many/most newer center turn lane roads in my area are also missing the arrows, perhaps that is no longer part of the California version of national recommendations.) In any case, the more usual tagging for a center turn lane is to use turn:lanes:both_ways=left. I did that on your section and the error/warning in JOSM went away. I did not save my changes as I usually try to limit my editing to areas I have actually visited or am planning on visiting and it will probably be a while before I get to the Sacramento area.

PhilCJ · 2017-12-21T22:23:00.000Z

Hi n76,

Thanks for taking a look, I made the change and saved it without error. Maybe the straight error is some kind of bug.

I have an issue with the results of making 47th Avenue a dual carriageway. Somehow I have an extra way that I don’t know how to delete.

It is at https://www.openstreetmap.org/edit#map=19/38.51045/-121.43748 on the eastbound part of the 47th ave

Can you suggest a way to delete the section to the right of the node where the dual carriageway nodes join?

Regards

PhilCJ

n76 · 2017-12-22T00:53:46.000Z

The dual carriageway was not actually connected to the two way section of 47th and there was no node on the two way section of 47th to split the way (to delete the extra). A difficulty was that there were two administrative boundaries that were sharing nodes with the road system, that always makes things harder. The short fix for that was to add a node to the “extra way” where where the dual carriage ways should connect to it and merge the nodes between that and the dual carriage ways. Second, to split the extra way and then delete the unneeded section.

I took the liberty of editing 47th between 54th and Elder Creek Road to show you how I’d do it. I hope you don’t mind. . .

Generally we don’t tag direction arrows (turn lanes) unless there is paint on the pavement. So I removed many of the “through lane” tagging.

I thought the intersection of 47th/Elder Creek and Stockton would be cleaner if the dual carriageways were not converted to single carriageways for the intersection alone. There were no traffic signals tagged at that intersection but from the imagery there appears to be signals there so I added them. I usually use the “tag incoming ways” method of adding traffic signals to an intersection if anything coming into it is a dual carriage way. I don’t normally tag crosswalks but the crossings were there already so I added footways but only for the intersection itself.

Between Steiner and Wire there is a service/access road parallel to 47th, if it follows the convention I see elsewhere in California it is likely also named 47th but I can’t tell from the imagery so I added it as an unnamed unclassified road, you will probably want to see what it is actually called and fix it.

The main reason I added that service/access road is because there was a service road at 38.5106202,0121.4415917 that erroneously connected to 47th but the imagery indicated it actually connects to the service road.

All these edits assume, of course, that the ERSI imagery I was looking at is current.

hadw · 2017-12-22T10:50:16.000Z

I still don’t believe that Elder Creek Road is a mere residential road. E.g. https://www.openstreetmap.org/way/23972516#map=16/51.5793/-0.3110 is much more residential in character but is still classified as tertiary. The only traffic you should expect on residential roads is vehicles accessing housing on that road and on the directly connected residential roads.

PhilCJ · 2017-12-22T15:40:58.000Z

Hi n76,

Thank you for investing your time to help me, you fixed my problem anticipated my next question about how to draw ways across intersections. I did make minor modifications to the lane count in the intersection. I liked your idea of keeping the lane count the same as the source way until the left turn way, so I applied it to throughout. I have to say that I really don’t like the way-star configuration where there is a central node for the intersection such as 47th Ave and Wire Drive…but that is for another day.

Your are correct the parallel road is also 47th Ave.

Do you know a pointer to adding lights using “tag incoming ways” ? I see you already took care of that but I’d like to know how to do.

Thank you also for putting in the pedestrian ways. I may extend these. This prompts one question that I’ve had for a long time, the width of the foot path is a configurable tag. I am looking how to tag widths for lanes, I see it in the OSM description but have not found it in an editor, do you do if there is an editor which supports configuring lane widths?

Hi hadw,

I agree with you, should it be secondary like Stockton, or Tertiary?

Regards

PhilCJ

n76 · 2017-12-22T16:27:44.000Z

PhilCJ:

Do you know a pointer to adding lights using “tag incoming ways” ? I see you already took care of that but I’d like to know how to do.

I am not aware of a tool or plug in that helps on tagging traffic lights. On one way highways it is easy, just put a node where the stop point is and then add a

highway=traffic_signal

tag. On two way highways you also need to add a

traffic_signal:direction=forward|backward

tag where forward/backward is the direction the traffic signal affects flow with respect to the direction the way was draw.

Stop signs are similar but, unfortunately the direction tagging does not use something like stop:direction but rather

direction=forward|backward

. The direction tag also has a totally unrelated semantic for other types of objects like mine entrances, etc. where the direction is either in degrees or north/south/east/west. I made mention about that use of one tag name with multiple contradictory uses on a tagging mail list and did not make much headway in getting people to acknowledge the problem much less consensus on what to do about it.

PhilCJ:

Thank you also for putting in the pedestrian ways. I may extend these. This prompts one question that I’ve had for a long time, the width of the foot path is a configurable tag. I am looking how to tag widths for lanes, I see it in the OSM description but have not found it in an editor, do you do if there is an editor which supports configuring lane widths?

I’ve not done much lane width tagging and haven’t looked for a plug in to help.

PhilCJ:

Hi hadw,

I agree with you, should it be secondary like Stockton, or Tertiary?

Regards

PhilCJ

My personal rule of thumb is that if there is no painted center line the road is unclassified, residential or service. If the authorities decided it is enough of a feeder to paint a center line then it is probably at least a tertiary. For suburban/urban roads, if it is mostly divided then it is probably at least secondary.

Urban primary to me is harder to define, at least now that I am in Orange County. In the Bay Area it seemed to be pretty clear: They were the main roads one would take that did not quite make the cut to be counted as a Santa Clara County expressway. However in Orange County there are a fair number of roads that people don’t seem to consider as major yet they are divided, often with three or more lanes in each direction, with speed limits of up to 55 MPH and relatively few traffic lights. In Santa Clara County they’d almost be expressways but here they people seem to feel they are of secondary importance. I often punt on these, leaving the classification as I found it and take solace in knowing that if the speed limits and traffic control (lights, signs, etc.) are properly tagged then navigation apps will find the best route regardless of the tagged classification being secondary or tertiary instead of primary.

PhilCJ · 2017-12-22T18:05:04.000Z

I looked at the whole of 47th Ave and Elder Creek Road and set to Tertiary since part of it was already Tertiary.

I looked for plugins that set lane width but could not find any. How do you edit the raw OSM code to add tags when not supported by an editor?

Regards

PhilCJ

n76 · 2017-12-22T18:21:02.000Z

PhilCJ:

I looked at the whole of 47th Ave and Elder Creek Road and set to Tertiary since part of it was already Tertiary.

I looked for plugins that set lane width but could not find any. How do you edit the raw OSM code to add tags when not supported by an editor?

Regards

PhilCJ

Using JOSM: With the object(s) selected, in the “tags” area on the right there is a “+ Add” button. Click on that. You can type what ever you want for the tag name in one field and tag value in the other field.

My guess is that for width of lanes you’d use the *:lanes tagging scheme. Default in OSM for measuring is meters. So assuming a one way road with three lanes, with the lane widths from left to right of 10ft, 10ft, 14ft I think you’d tag it:

width:lanes=3|3|4.27

Edit: From the wiki page on width at https://wiki.openstreetmap.org/wiki/Key:width, it looks like you can use the typewriter style single and double quote to specify feet and inches. So I think you could tag the above example as:

width:lanes=10'0"|10'0"|14'0"

PhilCJ · 2017-12-26T19:26:10.000Z

Thanks n76 !! (I have a big question at the end)

In JOSM when you click on + Add button in the tags section you get a dialog box that says this will change up to 1 object, it asks for:
1- a key with a pulldown menu, width was a choice but I could type in width:lanes
2 -a value with a pulldown menu, I could type in 12’0"|12’0"

Check out www.openstreetmap.org/way/548394802

The newly added tag even shows up in the simple editor under all tags, but if you click on the information it says “There is no documentation for this key”

The OSM XML looks like this

OK so now for my big question (drum roll): I would like to be able to associate a polygon with geo co-ordinates for each lane and way segment. Do you think this is possible, if not, how close to that do you think is possible?

Regards

PhilCJ

n76 · 2017-12-26T20:27:33.000Z

The tagging of width:lanes=* looks okay to me. Tag Info shows that width:lanes=* is not widely used (more in Europe than elsewhere). And while there is no wiki page documenting it, the :lanes and width= semantics are followed. https://taginfo.openstreetmap.org/keys/width%3Alanes

I am not sure I understand you follow up question. I suspect that you want to map the outline of the roadway was an area. There is a semantic for that (polygon tagged with highway=* and area=yes). Is that what you’d like to do? It does not seem to be widely supported by either map rendering or more specifically navigation apps. I suspect that most navigation software is broken with respect to handling that properly.

PhilCJ · 2018-01-04T15:19:52.000Z

Thank you hadw, alester, escada and n76

I think the junction is now looking good (although probably not perfect)

I took my broader polygon question for a new application to a new Forum topic “Polygon for each street segment that has different rules”

Any further suggestions would be appreciated

Thanks again

PhilCJ