At 2012-02-13 15:21, you wrote:
I've never been to Fresno, but I can't believe there would not be a
single primary road there. Still, that is the Truth According To
OSM[1]
I find that most areas where there has been little manual editing of the
TIGER import will have roads that are generally under-classified (i.e.
mostly highway=residential, with few if any higher-classed roads). I don't
know where TIGER's original classifications came from, but they don't seem
to match common sense very well or even documented sources, like city
general plans.
FWIW, TIGER 2011 is no better, and getting even worse in some other
respects, like naming errors.
...
A little research yielded this GP circulation map:
http://www.fresno.gov/NR/rdonlyres/5EA02A61-FCDE-41C2-B707-DDED0E820677/0/GeneralPlancirculation.pdf
(it's not clear if this "2025" map is projected or current - more
research). It seems to have five classifications above residential/local
(ignoring the "scenic" modifier), which I would map as follows:
Collector -> tertiary
Arterial -> secondary
Super Arterial -> primary
Expressway -> primary
Freeway -> motorway
Closer inspection of imagery or a survey might lead me to downgrade a
motorway or upgrade a primary to trunk, based on features like on/offramps,
etc. CA-99 used to have a lot of areas that were more trunk-like than
freeway, but it looks like it's been built up to freeway standards in this
area at least.
The Streets download listed here:
http://www.fresno.gov/Government/DepartmentDirectory/InformationServices/GIS/Layers.htm
has GPCIRC values which seems to correlate with the values shown in the map
with a little work (I can't find a data dictionary, but the coordinate
system seems to be CCS Zone 04, US Feet).
Who knows more about this situation? Are there any local mappers on
this list who can shed their light on this? Is this armchair mapping
gone awry? Someone who doesn't like red?
[1] http://www.openstreetmap.org/?lat=36.7974&lon=-119.7218&zoom=12&layers=M
--
martijn van exel
geospatial omnivore
1109 1st ave #2
salt lake city, ut 84103
801-550-5815
http://oegeo.wordpress.com
_______________________________________________
Talk-us mailing list
Talk-us@openstreetmap.org
http://lists.openstreetmap.org/listinfo/talk-us
--
Alan Mintz <alan_mintz+...@earthlink.net>
_______________________________________________
Talk-us mailing list
Talk-us@openstreetmap.org
http://lists.openstreetmap.org/listinfo/talk-us
