CA-23

[Quillz]

Bit of an oddball question, but is there a reason why CA-23 between CA-1 and US-101 follows Decker Cyn. Rd./Westlake Blvd. as opposed to Kanan-Dume Rd? The latter is a far better crossing of the Santa Monica Mountains, being both a bit shorter and much wider. It's virtually four lanes the entire length, as opposed to Decker Cyn, which is notoriously twisty and narrow.

Granted, it probably is simply the fact that Decker Cyn. Rd. is much older, being the only viable option at the time the route was defined, but it seems that it would be far more plausible for a numbered state highway to follow the best possible crossing of any given area. In this case, the Kanan-Dume Rd.

[Interstate Trav]

Bit of an oddball question, but is there a reason why CA-23 between CA-1 and US-101 follows Decker Cyn. Rd./Westlake Blvd. as opposed to Kanan-Dume Rd? The latter is a far better crossing of the Santa Monica Mountains, being both a bit shorter and much wider. It's virtually four lanes the entire length, as opposed to Decker Cyn, which is notoriously twisty and narrow.

Granted, it probably is simply the fact that Decker Cyn. Rd. is much older, being the only viable option at the time the route was defined, but it seems that it would be far more plausible for a numbered state highway to follow the best possible crossing of any given area. In this case, the Kanan-Dume Rd.

I believe it is that Decker Canyon is closer to the 23 Freeway.  The 23 was originally supposed to continue South Past the 101 to the Coast and be the Decker Canyon Freeway, if I'm not mistaken.  So the CA 23 number just got cosigned with the 101 to Westlake Blvd to Decker Canyon.

Kanan-Dume Road would be a better route in theory, but then you have to multiplex the 23 longer and the 23 wasn't supposed to go that far East.

[blawp]

It bothers me there's no longer any reassurance trailblazers for 23 south approaching the 101.

These signs were replaced by ones that exclude 23 after the widening was finished.





No mention of "Ventura Freeway" on the new signs either. Just a 101 shield.

[NE2]

It bothers me there's no longer any reassurance for 23 south approaching the 101.

Trailblazers. Reassurance reassures you that you're on the correct route after a junction.

[blawp]

oh ok.

[cahwyguy]

I believe it is that Decker Canyon is closer to the 23 Freeway.  The 23 was originally supposed to continue South Past the 101 to the Coast and be the Decker Canyon Freeway, if I'm not mistaken.  So the CA 23 number just got cosigned with the 101 to Westlake Blvd to Decker Canyon.

That argument would make sense only if the route had been defined post-freeways. In reality, Route 23 was defined in 1933 as legislative route 155. In fact, legislative route 155 encompassed the entire route from the coast highway to Fillmore.

[LRN 60] near Aliso Canyon to [LRN 2] near Triunfo
[LRN 2] near Newbury Park to [LRN 79] near Fillmore

LRN 60 was the coast highway, LRN 2 was US 101. So I think the simple fact was that the state selected Decker Canyon. Remember: The canyon road predated Kanan-Dume, especially before the three tunnels were constructed on Kanan-Dume (and I think those date back to the 1950s -- I'll check next time I drive it).

[jdbx]

On a related tangent, I drove Kanan-Dume for the first time on Sunday and was struck by how unusual it was to see streetlights along such a rural road.  I haven't driven many of the canyon roads in Southern California, but I cannot think of a similarly rural road up in the Bay Area that has street lights along its entire length.  Does anybody else find this arrangement to be unusual?  The lighting is a nice feature, it just seemed out-of-place compared to what I am accustomed to.

[Quillz]

I think it's simply there to improve visibility, as the road can be twisty. And coupled with that plus the fact it's almost four lanes wide for its entire width, I think it's clearly designed to be the best route through the Santa Monica Mountains. That's why I felt it would have been better as CA-23 rather than Decker Cyn. Rd.

[jrouse]

It bothers me there's no longer any reassurance trailblazers for 23 south approaching the 101.

These signs were replaced by ones that exclude 23 after the widening was finished.





No mention of "Ventura Freeway" on the new signs either. Just a 101 shield.

The disappearance was probably due to the fact that State Route 23 "breaks" at US-101 and there probably aren't a lot of people who will jump from one piece of 23 to the other.  I'm not saying I think this is the right way to do things...I think multiplexes should be signed.  I'm just giving you a possible explanation.

Joe
(Please note that I work for Caltrans but I do not speak for them on this board)

[TheStranger]

The disappearance was probably due to the fact that State Route 23 "breaks" at US-101 and there probably aren't a lot of people who will jump from one piece of 23 to the other.  I'm not saying I think this is the right way to do things...I think multiplexes should be signed.  I'm just giving you a possible explanation.

Joe
(Please note that I work for Caltrans but I do not speak for them on this board)

Thanks for the info Joe.  What I wonder: how many CalTrans districts are great at signing concurrencies?

The recent addition (last 5-6 years) of Route 113 trailblazers along I-80 between Dixon and Davis was pretty neat, while Route 99 is inconsistently signed along I-5 in Sacramento.

IIRC the 22/405 overlap in western Orange County is signed well, but 5/10 along the southern (non-former US 99) portion of the Golden State Freeway isn't consistent.

101/2 has a couple of signposts west of Downtown Los Angeles.

[Quillz]

The CA-1/US-101 overlaps are almost never signed, especially the fairly long segment between Ventura and just past the Gaviota Tunnel.

[jrouse]

The disappearance was probably due to the fact that State Route 23 "breaks" at US-101 and there probably aren't a lot of people who will jump from one piece of 23 to the other.  I'm not saying I think this is the right way to do things...I think multiplexes should be signed.  I'm just giving you a possible explanation.

Joe
(Please note that I work for Caltrans but I do not speak for them on this board)

Thanks for the info Joe.  What I wonder: how many CalTrans districts are great at signing concurrencies?

The recent addition (last 5-6 years) of Route 113 trailblazers along I-80 between Dixon and Davis was pretty neat, while Route 99 is inconsistently signed along I-5 in Sacramento.

IIRC the 22/405 overlap in western Orange County is signed well, but 5/10 along the southern (non-former US 99) portion of the Golden State Freeway isn't consistent.

101/2 has a couple of signposts west of Downtown Los Angeles.

Based on my limited observations, I would say that most districts are pretty good at signing multiplexes.  The areas where we are not that good in signing is multiplexing on freeways, and that's because of the route "breaks" that I mentioned earlier.  The route intersecting the freeway, particularly if the freeway is interstate, is almost always the one that "breaks", and therefore it doesn't always get sign continuity on the multiplex.  As you pointed out, District 3 is particularly bad with this in Sacramento with Route 99.  The I-10/I-5 multiplex in Los Angeles is signed well for motorists continuing on I-10, but not for motorists on I-5.

Another poster mentions the California 1/US-101 multiplex between Ventura and Gaviota.  There is actually a reason why that multiplex is not signed.  Route 1 merges with US-101 in Ventura, and then separates from it a little ways north of the city at Exit 72/State Beaches (a northbound exit only).  There are no trailblazers for Route 1 at this exit.  The highway itself is unsigned as California 1, although it has other standard state highway signing on it. It runs parallel to US-101 and intersects with it again at Exit 78/Seacliff and continues a short distance past there, before terminating at Mobil Pier Road undercrossing.  The Streets and Highways Code indicates that it breaks at US-101 at this location, but there are no ramps at this undercrossing.  For purposes of route continuity, one would have to get onto US-101 at the Seacliff interchange.

The multiplex in Ventura is signed on overhead signs in the southbound direction at the junction with Route 126.  It is not signed in the northbound direction.

[flowmotion]

Well, the CA 99 duplex through Sacramento doesn't officially exist. (see http://www.cahighways.org/097-104.html#099 )

My memory is that it used to be pretty thoroughly signed, however about ten years ago they pulled down the reassurance markers and changed some of the BGSs to read "TO CA 99".

[TheStranger]

Well, the CA 99 duplex through Sacramento doesn't officially exist. (see http://www.cahighways.org/097-104.html#099 )

Isn't that true for all concurrencies in California though, i.e. 10 on the Golden State Freeway, Route 35 along I-280, et al.?    (Where one route is the defined through route, and the other is given a defined break between the two endpoints of the concurrency)

The best signage for 99 along 5 is near the American River, and in parts of downtown.  On US 50 it's primarily restricted now to signs along W and X Streets, though westbound after the ramp for 99 south splits off, it is signed as mainline Route 99.

[jrouse]

Well, the CA 99 duplex through Sacramento doesn't officially exist. (see http://www.cahighways.org/097-104.html#099 )

Isn't that true for all concurrencies in California though, i.e. 10 on the Golden State Freeway, Route 35 along I-280, et al.?    (Where one route is the defined through route, and the other is given a defined break between the two endpoints of the concurrency)

Yes, that is true, and generally it is the state sign route that breaks when it runs concurrent with an Interstate or US route.  I'm not sure what the order of precedence is when it comes to multiplexing two state routes.

[TheStranger]

Well, the CA 99 duplex through Sacramento doesn't officially exist. (see http://www.cahighways.org/097-104.html#099 )

Isn't that true for all concurrencies in California though, i.e. 10 on the Golden State Freeway, Route 35 along I-280, et al.?    (Where one route is the defined through route, and the other is given a defined break between the two endpoints of the concurrency)

Yes, that is true, and generally it is the state sign route that breaks when it runs concurrent with an Interstate or US route.  I'm not sure what the order of precedence is when it comes to multiplexing two state routes.

Some examples, just to provide context (I'm not sure either what the order would be, myself) -

- Route 4 is defined to break at Route 99 in Stockton
- Route 12 is defined to break through Napa along its signed concurrency with Route 121 and Route 29...and at Route 99 in Lodi
- Route 14 breaks at Route 58 in Mojave
- Route 23 breaks at Route 118 in Simi Valley

The strangest one - though not state/state - is Route 271 being a two-segment route with no signage in the middle along US 101 (from what I've heard - never been that far northwest) but defined as a one-segment road!

[agentsteel53]

The strangest one - though not state/state - is Route 271 being a two-segment route with no signage in the middle along US 101 (from what I've heard - never been that far northwest) but defined as a one-segment road!

as of 2009, there is indeed no signed 101/271 multiplex.

[myosh_tino]

Some examples, just to provide context (I'm not sure either what the order would be, myself) -

- Route 14 breaks at Route 58 in Mojave

With the completion of the Mojave Bypass, wasn't old 58 (signed as Business 58 at the interchanges connecting the old with the new) relinquished to the city of Mojave?  If so, wouldn't it make sense to transfer the old concurrency through Mojave to Route 14?

Yes, that is true, and generally it is the state sign route that breaks when it runs concurrent with an Interstate or US route.  I'm not sure what the order of precedence is when it comes to multiplexing two state routes.

IINM, isn't Route 35/I-280 and Route 1/I-280 co-signed in San Mateo county?  I remember seeing reassurance shields for both routes on mainline I-280 but according to cahighways.org, there are breaks in 35 and 1 where it runs concurrent with I-280.  Perhaps the co-signing was done for navigational purposes?

[TheStranger]

Some examples, just to provide context (I'm not sure either what the order would be, myself) -

- Route 14 breaks at Route 58 in Mojave

With the completion of the Mojave Bypass, wasn't old 58 (signed as Business 58 at the interchanges connecting the old with the new) relinquished to the city of Mojave?  If so, wouldn't it make sense to transfer the old concurrency through Mojave to Route 14?

I think the former 14/58 (years ago, 6/466) concurrency is now part of 14 solely, yet still the route break remains in the definition!

(This is why I personally wish concurrencies were actually defined, rather than left ambiguous.  Also highlights yet another weakness in requiring legislative definition of routes, as opposed to CalTrans defining routings themselves)

Yes, that is true, and generally it is the state sign route that breaks when it runs concurrent with an Interstate or US route.  I'm not sure what the order of precedence is when it comes to multiplexing two state routes.

IINM, isn't Route 35/I-280 and Route 1/I-280 co-signed in San Mateo county?  I remember seeing reassurance shields for both routes on mainline I-280 but according to cahighways.org, there are breaks in 35 and 1 where it runs concurrent with I-280.  Perhaps the co-signing was done for navigational purposes?

1/35 and 280/35 are both well-signed.  101/84 is pretty decently signed as well, though for some reason Willow Road eastbound (former signed 84, presently just hidden 114 with two shields for that route at its west terminus) isn't signed for the "Dumbarton Brudge" from 101 north like it used to be.

114 and 109 I think are the only unsigned state routes in San Mateo County, everything else - and all noted concurrencies - are.

[TheStranger]

Tonight I passed through the 101/1 interchange in San Francisco's Presidio...

Northbound on 1, the mainline lanes are signed (towards the ramp to 101/1 north heading for the Golden Gate Bridge) for "US 101 North - Golden Gate Bridge."  No mention of the concurrency with 1.

I really wonder if practices are very district-specific for co-signing.

[myosh_tino]

Tonight I passed through the 101/1 interchange in San Francisco's Presidio...

Northbound on 1, the mainline lanes are signed (towards the ramp to 101/1 north heading for the Golden Gate Bridge) for "US 101 North - Golden Gate Bridge."  No mention of the concurrency with 1.

I really wonder if practices are very district-specific for co-signing.

If I'm not mistaken, the Golden Gate Bridge is technically not a part of US 101 because the bridge is privately owned.  Looking at Daniel Faigin's site (cahighways.org), there is indeed a break in US 101 at the Golden Gate Bridge.

Interestingly enough, there is at least one reassurance assembly on southbound US 101 that shows the concurrency with CA-1... http://www.google.com/maps?ll=37.877822,-122.513668&spn=0.002227,0.003449&hnear=Cupertino,+Santa+Clara,+California&t=m&z=18&layer=c&cbll=37.877852,-122.513747&panoid=EKvhcD1nGIerKpo-rRnlpw&cbp=12,161.46,,0,0

[TheStranger]

If I'm not mistaken, the Golden Gate Bridge is technically not a part of US 101 because the bridge is privately owned.  Looking at Daniel Faigin's site (cahighways.org), there is indeed a break in US 101 at the Golden Gate Bridge.

I wonder if the AASHTO definition of the route includes the bridge (I know legislatively it isn't such). 

Then again, that short segment of 101 between 1 and the bridge IS concurrent with 1 - and as you mentioned, the two routes are signed in southern Marin County together.

[NE2]

I wonder if the AASHTO definition of the route includes the bridge (I know legislatively it isn't such). 

Of course it does. The only gaps are ferries and Yellowstone (and US 2).

[myosh_tino]

I wonder if the AASHTO definition of the route includes the bridge (I know legislatively it isn't such). 

Of course it does. The only gaps are ferries and Yellowstone (and US 2).

and you know this because...  I'm not doubting your intelligence, I just want to know where you got your information because the way you phrased it, it sounded like "of course it does silly!".  I tried to do a google search for the AASHTO definition of US 101 but was unable to find it.

[NE2]

and you know this because...

...because AASHTO doesn't stop the definition every time a toll bridge is crossed.
http://www.transportation.org/default.aspx?siteid=68&pageid=1760 (p. 144)