[Talk-us] I've been workin' on the railroad (in California)

Paul Johnson baloo at ursamundi.org
Fri Jan 16 05:06:43 UTC 2015

On Thu, Jan 15, 2015 at 10:38 PM, stevea <steveaOSM at softworkers.com> wrote:

> And here is what I've learned.
> This is tedious work, especially a state at at time.  It is slow, but that
> is because it is a whole (large) state.  This is not impossibly large work,
> not by a long shot.  Yet for one person, a whole state is a lot of work.
> For one railroad (elephants are eaten best one forkful at a time) this sort
> of effort is not difficult, and the rewards in new renderings are available
> "tomorrow."

Break it down by county (possibly by county district, given some of the
really large ones like San Bernardino, or the real rail dense ones along
the coast).  Do the rail yards first, the rest becomes a cakewalk.

> It is important to use the name= tag to unambiguously (assert) a name for
> an aggregation of rail segments into a Subdivision or Line (or Lead if
> usage=industrial or service=spur).  This is especially true as OSM now
> often has messy rail around yards and regarding whether there is
> single-track or double-track in many or most places.  What I am saying is
> that we work to do to be more accurate.  And, this work is doable.

When in doubt, I move the TIGER-imported name to operator (since it often
is) and leave name blank if I don't know the lead or subdivision or line.
There seems to be some confusion about this since I've noticed people will
rename segments of TriMet's MAX system to "Metropolitan Area Express" after
I've attempted to put the proper name of the line (and not the whole
system) on the lines (and some folks keep adding oneway=yes to MAX lines
despite it's dual line running and operation on one-way streets, the only
place where one-way operation is always true is the loop on Fifth and Sixth
avenues and one track of the Steel Bridge based on my knowledge of TriMet's
rail operations rulebook and confirmed by repeated ground observation
seeing trains operate on opposite the usual track circa when the Green Line

> Both tags on ways and tags in relations are supported, but it appears tags
> on ways supercede.  I find that in the USA, because of the way that TIGER
> tags have put much rail into parts of North America, adding usage= tags to
> ways is often how things begin.  Then these get aggregated into type=route,
> route=railway relations.  I have not yet explored the multiple possible
> options of how tagging might supercede except as above.

Annoyingly, the Transit layer also seems to be exceptionally bus-oriented
and doesn't render routes on rail lines, as well.  This has led to some
locales, such as folks interested in mapping the IRT and BRT in New York
City, to tag for the renderer, putting routes in parenthesis in the name
tag on stations.  The renderer also ignores line color, which can be
defined in the tagging (and is often, such as in Portland, which uses red,
yellow, green, blue, and plans to use orange, brown and used to use black,
the only way to identify the line).

> That said, a much richer branching structure certainly exists (requiring
> appropriate tagging).  Sidings, yards and signalling are crude or virtually
> nonexistent, though there in some measure.  Speed limit data are virtually
> nonexistent.

To some extent, given that signs, signals and speed orders, change more
often along rails than along roads, tends to be rather fluid, and are often
located in places where, unless you're a frequent rider of a passenger
service or work for the line, aren't readily verifiable legally
(trespassing on a railroad is srs bsns, both legally and in terms of
personal danger).

> Private corporation rail data are not likely compatible with our ODBL,
> though it doesn't hurt to ask (for explicit permission). Public rail data
> from a state with "generous" public record laws (such as crossing
> spreadsheets) can be quite helpful to identify names (based on road
> crossings, city/county and/or lat/long data) of Subdivisions, Lines and
> Leads.

I wish I had this.  Though there gets to be overkill, too, for example,
every speed limit in Oregon is published, from the smallest alleyway to the
largest segments of I 5, and everything in between.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-us/attachments/20150115/f09c3d81/attachment-0001.html>

More information about the Talk-us mailing list