User:Btwhite92/Draft:California Highways

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Classifications at-a-glance
Rural Urban
Motorway Freeway
Trunk Principal inter-regional highway Urban expressway
Primary Major intra-regional highway Major urban arterial
Secondary Minor highway Minor urban arterial
Tertiary Rural collector Urban collector

Determining roadway classification

Motorway

Freeways. This includes all interstate highways, as well as many portions of US, state, and occasionally local highways. Must adhere strictly to the following criteria:

  • Divided carriageway
  • Full access control
  • Access by on/off ramp only (except for freeway beginning/endings, which are handled below)

California posts white regulatory "Begin Freeway" and "End Freeway" fairly rigorously at the beginning and ending of freeways. So long as the roadway meets the above criteria, highway=motorway tagging should begin and end at this signage where it is present, and the signs themselves tagged with traffic_sign=US:CA:R57 for "Begin Freeway" and traffic_sign=US:CA:R58 for "End Freeway". See User:Btwhite92/Draft:List of freeway endings in California for documentation of the location and existence of this signage on all California freeway beginning/endings, as well as how to handle cases where signage is not present or posted in an invalid location.

Trunk

Trunk roads carry principal "long-haul" connections between major regions in the absence of a motorway. They are usually built to a high standard, allowing high-speed travel and generally carrying a noticeable amount of freight traffic. In mountainous areas, these roads typically have frequent passing lanes and smoother curve geometry than other highways. Many of these roads carry current US highway alignments, or formerly carried now-abandoned alignments.

There is no deterministic way to classify trunk roads, and there are many factors to consider. A roadway being part of the National Highway System, designated as an "Other Principal Arterial" or higher on state functional classification maps, or being part of a Strategic Interregional Corridor are indicative of a trunk road, but not necessarily conclusive.

Ideally, there should be few enough community-approved trunk routes in CA that they can be enumerated in a table like below. Once this table is fairly settled, tagging guidance should encourage those that think a route should be/not be tagged as highway=trunk based on importance, ought to consult with the local community first before making any changes.

Proposed California trunk routes
Region Route Start End NHS FC CA SIC Notes
Statewide US 101 I 5 OR state line Yes Other Fwy or Expy, Other Principal Arterial Yes
Statewide US 395 I 15 OR state line Yes Other Principal Arterial Portions Northern portion carries Reno <-> Bend/Willamette, Redding <-> Boise routes
Northern US 199 Crescent City OR state line Yes Other Principal Arterial No Carries Eureka <-> Medford route
Northern US 50 Sacramento NV state line Yes Other Fwy or Expy, Other Principal Arterial Yes
Northern US 97 Weed OR state line Yes Other Fwy or Expy, Other Principal Arterial No Main N/S route through central OR
Northern CA 99 Sacramento Red Bluff Yes Other Fwy or Expy, Other Principal Arterial Portions Former US highway; many portions freeway/expressway
Northern CA 70/149 CA 99 south interchange CA 99 north interchange Yes Other Fwy or Expy, Other Principal Arterial Yes
Northern CA 299 Eureka/Arcata Redding Yes Other Principal Arterial Yes
Northern CA 36/44 Redding US 395 intersection Yes Other Principal Arterial Yes
Northern CA 89 CA 44 intersection I 5 intersection Yes Other Principal Arterial No Carries Reno/Tahoe <-> Medford route
Northern CA 20/53/29 US 101 intersection I 80 intersection Yes Other Principal Arterial Yes Trunk route follows south around Clear Lake - Caltrans documentation states CA 20 north of Clear Lake is geographically constrained and that highway development will be focused on the southern portion of the loop
Northern CA 49 Auburn Grass Valley/Nevada City Yes Other Principal Arterial Yes
Northern CA 65 Roseville Yuba City/Marysville Yes Other Fwy or Expy, Other Principal Arterial No Mostly freeway or expressway; short two-lane highway segment

Urban expressways

Primary

highway=primary routes augment the freeway and trunk system by carrying traffic for the majority of trips within a region and providing through connections for smaller towns to the principal road network (motorway/trunk). Regionally important, but less important for cross-country travel.

In rural areas, major highways that circulate the majority of traffic within a region, as well as serving to connect significant towns (typically of population 10,000 or more, but may be much less in very rural parts of the state). These highways usually share the following characteristics:

  • Signposted CA state highway (though may occasionally be a county highway or minor US highway)
  • Part of the CA Freeway and Expressway System (though not always)
  • High quality two-lane highway at a minimum
  • In mountainous regions, slower going and tighter curve geometry than nearby highway=trunk routes
  • Through route (no dead-end rural primary roads)
  • Maintained and open year-round

In urban areas, major urban arteries that carry more through traffic or provide a "better" route (by virtue of posted speed, lane count, connectivity, etc) through an urban area than nearby highway=secondary routes. The physical characteristics of these roads depends heavily on the type of development they are located within.

  • In dense urban areas, these routes are typically recognized by having more lanes and a higher posted speed limit than other arteries.
  • In the downtown area of less dense urbanized areas, these are typically the "Main Street".
  • In suburban areas, these are usually major high-speed "boulevards" that augment the nearby freeway/expressway system.

Highways which do not carry major through traffic, or do not provide a clearly "better" route through an urban area should likely be tagged highway=secondary or less.

Secondary

Tertiary

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