Alternate Interstate 405

[emory]

While headed to the west side on Saturday for a party I got off at the Venice/La Cienega exit on the 10 going west. On the exit is an ALTERNATE SOUTH I-405 shield. A second shield appears on Cadillac Avenue between Venice and La Cienega. The shields look like they've been there a while. I don't recall seeing any on La Cienega south. Are there any others up?

[briantroutman]

I'm living on the west side of LA for a few months and just yesterday was headed to Randy's Donuts at La Cienega and Manchester, and coincidentally I noticed, not an ALTERNATE I-405 but an ALTERNATE I-10 on La Cienega right before the intersection. The I-10 shield looked fairly recent, but it was mounted above a very badly faded 405.

https://www.google.com/maps/@33.961077,-118.370025,3a,37.5y,359.71h,87.98t/data=!3m4!1e1!3m2!1s8AyWogSlBKziu_sda0gEiQ!2e0

[JustDrive]

There was an "Alternate 10" sign on NB 405 at La Tijera, though there's no signage on La Tijera at La Cienega pointing towards the 10.

[TheStranger]

IIRC, isn't there signage for a 10/60 alternate routing using the Mission Road ramps from southbound US 101/Santa Ana Freeway approaching the San Bernardino Split?

[agentsteel53]

While headed to the west side on Saturday for a party I got off at the Venice/La Cienega exit on the 10 going west. On the exit is an ALTERNATE SOUTH I-405 shield. A second shield appears on Cadillac Avenue between Venice and La Cienega. The shields look like they've been there a while. I don't recall seeing any on La Cienega south. Are there any others up?

the ALT I-405 assemblies are all over Sepulveda Blvd.  I believe that is the official alternate from at least I-10 north to the northern terminus, but the signage is extremely spotty.

[OCGuy81]

Interesting, I haven't seen these in Orange County at all, and I didn't think Caltrans really signed Alternates.  May have to cruise up north to see these.

[agentsteel53]

I didn't think Caltrans really signed Alternates

seems to be a district 7 thing; I don't know of any offhand anywhere else. 

[TheStranger]

I didn't think Caltrans really signed Alternates

seems to be a district 7 thing; I don't know of any offhand anywhere else. 

The only "alternate" I can think of outside of District 7 is the sometimes-signed Alternate US 50.

[emory]

I didn't think Caltrans really signed Alternates

seems to be a district 7 thing; I don't know of any offhand anywhere else.

Can Caltrans just sign roads they don't maintain? La Cienega Blvd. is maintained by Los Angeles County. I'm kind of surprised they didn't give it a county route number considering it's part freeway/expressway.

[TheStranger]

Can Caltrans just sign roads they don't maintain?

Short answer: no.

Slightly longer answer: This specifically relates to the concept of routes being legislatively defined (and why, when a route is relinquished from state control, many clauses are usually added in terms of future signage status, etc.).

Given that numbered routes should primarily (IMO) be meant as navigational aids, I'm not a fan of the aftereffects of the legislative numbering system at all.

[sdmichael]

To my knowledge, these "Alt" routes are/were due to the heavy construction and closures along I-405 and I-10 (by default with its connection to I-405). They aren't standard "Alt" routes.

[mrsman]

Can Caltrans just sign roads they don't maintain?

Short answer: no.

Slightly longer answer: This specifically relates to the concept of routes being legislatively defined (and why, when a route is relinquished from state control, many clauses are usually added in terms of future signage status, etc.).

Given that numbered routes should primarily (IMO) be meant as navigational aids, I'm not a fan of the aftereffects of the legislative numbering system at all.

I believe that the section of La Cienega from the 405 to the 10 should be some kind of county route number.  It would be fairly easy to greenout the existing "42" on the 405 northbound exit at Manchester / La Cienega.

This is a great shortcut route that is majority expressway and it should be signed on fairly large signs that this is a better way to make the 405-10 connection.  I'm very familiar with the route, since this was part of my Hollywood - El Segundo commute in the late 90's.

From 405 northbound:  I-10 EAST Los Angeles, USE [N9] (or other number) NORTH, next exit.

From 10 westbound:  I-405 SOUTH LAX, Long Beach, USE [N9] SOUTH, next exit

And instead of following I-10 alts or I-405 alts along La Cienega, there will be [N9] shields up and down.

In my book, every limited access highway should incorporate some type of control city, and in this case LAX would clearly be a perfect southbound control city until the La Cienega / La Tijera intersection.  Northbound control city should be Los Angeles, as it does lead people toward I-10 east and Downtown L.A.

[Henry]

I remember thinking that Interstates aren't supposed to have any "Alt" routes in the sense that US and state routes do. And since we're on the subject, the only other example I'm aware of is Alt I-70 in Kansas City, which takes up part of the Alphabet Loop, IIRC.

[sdmichael]

The signage has been around a while. This one dates to the late 1990's or early 2000's and was near the Sepulveda / Centinela ramps.

[emory]

To my knowledge, these "Alt" routes are/were due to the heavy construction and closures along I-405 and I-10 (by default with its connection to I-405). They aren't standard "Alt" routes.

You'd think they'd use orange DETOUR signs instead.

Can Caltrans just sign roads they don't maintain?

Short answer: no.

Slightly longer answer: This specifically relates to the concept of routes being legislatively defined (and why, when a route is relinquished from state control, many clauses are usually added in terms of future signage status, etc.).

Given that numbered routes should primarily (IMO) be meant as navigational aids, I'm not a fan of the aftereffects of the legislative numbering system at all.

I believe that the section of La Cienega from the 405 to the 10 should be some kind of county route number.  It would be fairly easy to greenout the existing "42" on the 405 northbound exit at Manchester / La Cienega.

This is a great shortcut route that is majority expressway and it should be signed on fairly large signs that this is a better way to make the 405-10 connection.  I'm very familiar with the route, since this was part of my Hollywood - El Segundo commute in the late 90's.

From 405 northbound:  I-10 EAST Los Angeles, USE [N9] (or other number) NORTH, next exit.

From 10 westbound:  I-405 SOUTH LAX, Long Beach, USE [N9] SOUTH, next exit

And instead of following I-10 alts or I-405 alts along La Cienega, there will be [N9] shields up and down.

In my book, every limited access highway should incorporate some type of control city, and in this case LAX would clearly be a perfect southbound control city until the La Cienega / La Tijera intersection.  Northbound control city should be Los Angeles, as it does lead people toward I-10 east and Downtown L.A.

How about calling it County Route 170?