Peter Dobratz writes:
I don't see any specific information about exactly how one would go about identifying specific railways in Oregon so that they could be added to relations.
Yes, Peter: I did that on purpose because I want to encourage OSM mappers to develop their own methods for "discovering" the names of rail subdivisions. One way I did this in California was to use our state's Public Utilities Commission (PUCs are state agencies that regulate railroads and other public utilities) "Road/Rail Crossing Spreadsheet." Oregon's PUC likely has something similar (as should all other states). It shows all Road/Rail crossings in the state, along with the name of the subdivision/rail line. If you sort the sheet by the subdivision/line name, then milepost, you can essentially trace the rail line along known (already in OSM) streets/avenues/boulevards. This allows you to reverse engineer the name of an existing (TIGER-entered, poorly named) rail line in OSM as you can identify it by known landmarks (streets).
Part of the reason I do this is because other places you might "discover" these data (subdivision names) are maps published by the rail corporations. But, be careful. For example, I have found that when I go to Union Pacific's web site to get a page that displays their network map, I get a "login screen" or a very high-zoom level map which is clearly copyright protected, meaning OSM cannot enter those data. However, a map I found on BNSF's web site [1] is clearly NOT copyright protected, so I believe I can use those data. These are usually very high-zoom level maps, meaning they are only useful to "confirm" that an existing line (again, from TIGER) has a certain name. They are not sufficient/detailed enough to enter the rail data from scratch.
Are there signs on the ground with these things?
No, there are usually not. Occasionally you will see a sign that says something like "Entering Seabright Block" but these are often traffic signalling areas, not entire subdivisions which are usually long -- hundreds of km -- stretches of contiguous rail. However, this doesn't mean that they are unnamed, just poorly signed. Rail companies name them internally, but because rail companies are regulated, they report these names to PUCs, and therefore "give them" to the public. It's just that the data can be difficult to discern. Persevere!
For the railways, Paul may be objecting to the content of the name and ref tag on the Way objects themselves for the railway. However, it is not clear how to find out what the name actually should be. The wiki page does indicate that the name tag on the Way objects should match the name tag on the Relation object with type=route and route=railway tags. For many rails around Portland, these Relations (type=route, route=railway) have not yet been created.
Yup. So: 1) "Discover" the correct names for rail infrastructure segments, 2) Tag them as such (usually the existing TIGER name= correctly can become the operator= tag), 3) Give them a usage= tag and 4) Collect into a route=railway relation identically named rail segments. That is the important work that has been underway in California (and many other states) for the past several months. Especially if usage= tags are also applied to rail segments, ORM will display these with a pleasing contiguous line. Yes, usage= tags can be a bit nebulous to determine, too, just do your best using these [2] guidelines.
You mention 2 specific examples (type=route; route=railway): Brooklyn Subdivision (<http://www.osm.org/relation/2203588>http://www.osm.org/relation/2203588) and Fallbridge Subdivision (<http://www.osm.org/relation/1443651>http://www.osm.org/relation/1443651). Some of the Way objects in Fallbridge Subdivision are also contained in <http://www.osm.org/relation/4734792>http://www.osm.org/relation/4734792. Both of the relations for Fallbridge Subdivision have FIXME tags expressing uncertainty about exactly where the route Relation should begin and end. How would one determine the exact end of the Relation for the Fallbridge Subdivision?
It looks like I made an error by adding 4734792, as I didn't see the existing 1443651. I believe this is a forgivable mistake, and I'm sorry I made it. I will remove 4734792 forthwith. Regarding how to determine where the exact boundaries are: I can't give you a perfect answer in every case. Often, subdivisions begin and end at a yard, a junction or a station, but not always. The rail owner gets to say definitively, and again, the PUC should document this (somewhere).
Also, looking through the history of the above relations, I can't really find anything in the changeset tags regarding the source of the data about the railroads. Where do the names Brooklyn Subdivision and Fallbridge Subdivision come from?
The names come from the rail company/owner of the line. Especially for rail with passenger routes, this will often be a public agency, like a state Department of Transportation or a local transit authority.
Paul mentions that we should be using the name "Banfield Mainline" but where does that name come from and what exactly does it refer to?
http://en.wikipedia.org/wiki/MAX_Light_Rail should explain it, or at least introduce it. You might address Paul directly with this question.
I am happy to answer other specific questions, but let's take them off-list. We can re-post if needed.
SteveA California [1] http://www.bnsf.com/customers/pdf/maps/subdivisions-map.pdf[2] http://wiki.openstreetmap.org/wiki/OpenRailwayMap/Tagging_in_North_America#Route_Importance
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