[Talk-us] Prioritizing multi-banded route designators (multiple overlaps) on ways: the "Principal route designator" concept

[Kerry Irons]

Peter,

 

The "Miracle Mile" is probably an anachronistic reference, but I believe it
is a reference for a section of Chicago's Lake Shore Drive (also US 41).
Other towns have used this reference to their business district.  Note the
reference in Billy Joel's "It's Still Rock and Roll to Me."  For people like
myself who visit Chicago, "the Dan Ryan" and "the Eisenhower" don't mean
much, but I-90 and I-290 appear not only on maps but on exit signs,
wayfinding signs, and mile posts.  In the US, FWHA and the MUTCD have
standards for route numbering signs and typically ALL of the routes on a
given piece of pavement show up at key junctions (mile post signs will only
have the primary route, however that was determined).

 

My point here is that map users want to see all the route numbers on a given
piece of pavement, not just the primary route.  While OSM is very good about
capturing all the information in tags, if only one route number appears at
any given zoom level, those using the standard layer will not see the other
routes (they are visible in the MapQuest Open layer).  And in some cases,
multiple route number tags apparently cause the OSM Standard layer rendering
to simply not show any route number shields.  There is a section of I-75
near me that is also US-23.  In the OSM standard layer, neither of those
route numbers is visible at any zoom level for a 75 mile stretch of
interstate.  The same thing happens on US-41/M-28 west of Marquette, MI
until you get to z=13.  This is not a "user friendly" view for map users.

 

 

Kerry

 

From: Peter Davies [mailto:peter.davies at crc-corp.com] 
Sent: Saturday, December 21, 2013 11:30 PM
To: Kerry Irons
Cc: Tod Fitch; Martijn van Exel; OSM US Talk; Richard Welty; Eric Fischer
Subject: Re: [Talk-us] Prioritizing multi-banded route designators (multiple
overlaps) on ways: the "Principal route designator" concept

 

Kerry

 

I'm not sure that I follow your drift here, Kerry.  Can you elaborate about
the Miracle Mile?

 

Peter  :)

 

On Sat, Dec 21, 2013 at 6:45 PM, Kerry Irons <irons54vortex at gmail.com>
wrote:

All,

 

If you look at the guidance in the US from FHWA and the MUTCD, all route
numbers are to used in signage.  You never know who is using a given piece
of pavement by following which route number.  Just because the locals might
call it "the Miracle Mile" doesn't mean that is the appropriate choice for
shield priority.

 

 

Kerry

 

From: Peter Davies [mailto:peter.davies at crc-corp.com] 
Sent: Saturday, December 21, 2013 8:53 PM
To: Tod Fitch
Cc: Kerry Irons; Martijn van Exel; OSM US Talk; Richard Welty; Eric Fischer
Subject: Re: [Talk-us] Prioritizing multi-banded route designators (multiple
overlaps) on ways: the "Principal route designator" concept

 

Tod,

 

I found a common stretch of CA 108 and CA 120 between Oakdale and Yosemite
Junction in Tuolumne County.  I'm not sure if that's the double-banded
section you mention.

 

As Eric Fischer said, there are some ways that carry two approximately equal
routes, and my suggestion was that they would both still feature in the way
ref tags, in this case "CA 108;CA 120" (which is in fact what OSM currently
has for these ways).  I agree that there is no obvious precedence order in
this case other than "highest system, lowest number" (which is again what
OSM has at present).

 

My suggestion was (and is) that if we need to have multiple refs, because
two or more routes are about equal, the "way refs" be listed in shield
posting order, starting with the top or left-most shield.  Without going
there, we won't know if that is CA 108 or CA 120, or whether it varies.
Since both are about equal it probably doesn't matter, because (as you say)
both should probably be mentioned.  

 

My interest was more in what Shawn Quinn calls "rubbish numbers", such as US
and state route refs multi-banded on an interstate.  I think he argues that
we need them all.  I don't think that's in doubt, either.  But do we need
them all to be listed in every way ref, or would it be sufficient to have
them in the relation refs, with the first listed shield(s) emphasized in the
way refs?

 

I think the answer is already emerging.  Way ref tags with complete lists of
overlapping secondary route designators are here to stay.  Personally I'm
happy about this so long as the first signed route number(s), starting from
the top and/or left of the direction signs and route confirmation signs,
come first in the way ref lists (as they usually do in OSM already).  So, I
465 should be listed before US 31, or IN 67, say, as it's given greater
precedence in the signing.  

 

In other words, most people probably think that Interstate 465 is Interstate
465, and not US 31 or IN 67.  So we should list it first (as we almost
always do).  Sound fair?

 

Peter

 

On Sat, Dec 21, 2013 at 4:37 PM, Tod Fitch <tod at fitchdesign.com> wrote:

On Dec 21, 2013, at 2:35 PM, Peter Davies wrote:

 

Kerry

 

<snip>

 

It's also perfectly fine if we want to keep all of the secondary designators
in the ways' ref tags, as long as the most important one is presented first.
We can easily ignore the less important numbers.  But without a way ref
(i.e., using only relation refs, as has been suggested) we have no way of
knowing what is the most common route designator for that specific way.

 

Peter

 

There may be no "most common route designator". A semi-local example: If I
am directing you east over Sonora Pass I'll tell you to go east on CA 108.
If I direct you to Yosemite I'll tell you to go east on CA 120. But for a
number of miles they are the same road with dual signage with no obvious
method of tell which one is the most common designator.

 

(You can probably tell what the road officially is by looking at the very
cryptic and hard to read version of a mile/information posts that CalTrans
uses but most motorists never notice them and if they do they are very
difficult to read or decipher without stopping.)

 

Some of your examples are in areas I am not familiar with. But in both the
San Francisco Bay Area and Los Angeles there are named freeways. I notice
that in the Bay Area the name is almost never used whereas in LA it seems
both are used with the name being more common. In either case I'd expect the
name key to specify the name and the ref to specify the route number. How
you decide that a local would be more likely to use the name (LA) or the ref
(SF) I haven't the fainted idea.

 

Tod

 

 

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