Headlines About California Highways - June 2019

[cahwyguy]

A quickie post between my three shows yesterday for the Fringe Festival, and my two shows today. Here are the headlines about California Highways in June. Ready, set, discuss.

Link: https://cahighways.org/wordpress/?p=15408

[djsekani]

The Mashable article incorrectly has a photo of the 110/105 interchange labeled as the 105/405 interchange. That should not bother me as much as it does.

As for the eight-lane section of CA-210 through the Inland Empire, any idea why that wasn't built as ten lanes from the get-go?

[Max Rockatansky]

The whole deal with Richardson Grove on US 101 turned into a huge deal on Facebook for a day or two.  Really I don't see how the current 101 can even slightly realistically be widened in that Redwood grove without doing a ton of damage. 

I have at least one trip over Tioga Pass planned next month. If all goes to plan there might be a second trip.  I just wish that I could get up there now to see how much snow is up there. 

The widening of 46 in Shandon has been a welcome addition but I'll be really glad when the junction of 46 with 41 north is replaced with flyover. 

Speaking of things that blew up on Facebook, the removal of the El Camino Bell At UC Santa Cruz sure generated...a lot of opinions.

[Max Rockatansky]

Kind of disappointing that the Disney article didn't go on to mention too much detail on Un-built CA 276 to Mineral King.  All the environmental red tape largely hit at all levels all at once at the start of the 1970s which culminated in the resort project being built.  It's interesting the Legislature never fully dropped the plans for CA 276 but rather scaled them back to the boundary of Sequoia National Park.  The existing Mineral King Road is haggard to be sure but is is also one of the most unique roads and places I've been to in California. 

[sparker]

Where to begin?  May as well just scroll down the laundry list and see what stands out.

First of all, the pavement issues with I-215 in the Moreno Valley/Perris area -- although the initial asphalt paving dates from the 1995 completion of the freeway in this area, from personal experience when I was living in Redlands from 2004 to 2009 was that the deterioration there was already apparent during that time.  Whether simply not adequate for the traffic load (and, to be fair, the population of the area -- and with it additional commuter traffic -- more than doubled since the freeway was opened) or just plain substandard would have to be investigated -- but this is not by any means a new issue -- but with the additional traffic load will come the likelihood of additional complaints about the problem.  Now -- whether something will be done about it in the near term will likely depend upon D8's operating budget, and whether there's enough slack in such to effect anything other than spot fixes.  This section will probably require a complete rework; seeing that it turns 25 years old next year it's overdue at this point.

The injunction against widening existing US 101 through Richardson Grove (a bad idea to begin with) may well provoke increased interest in the long-sought (by parties outside the Grove) freeway/expressway bypass.  OTOH, the fact that outbound lumber shipments from Rio Dell and Fortuna have declined precipitously over the last 30-odd years may mitigate against the perception (official and public) that a bypass is warranted.  Look for pressure from Eureka interests favoring such a project to clash with environmental activists -- just a continuation of the controversy that's existed since expansion of US 101 commenced in the late '50's; don't expect any sort of resolution.

So the PIRG has a "Top Nine" list?  Guess their budget didn't allow for the usual "top ten"!   Since they're vehement about opposing both new freeways and new exurban development, the High Desert Corridor slid neatly into their opposition packet.  The thing is -- the PIRG is pretty much "on their own" about this; unlike urban corridors, there's not a lot of aggrieved parties, or the potential for such, along the corridor's route to join this particular skirmish (except the usual like-minded PIRG allies) -- they're "preaching to the choir" with this policy position.  But one thing may come out of it if the corridor planning efforts are publicized -- even negatively; the rail aspect of the corridor could see itself being accelerated to development simultaneously with the highway.  If not HSR, it does connect to Metrolink at its west end; an extension of the Lancaster Metrolink line to Adelanto or Victorville could be considered.  Ironically, it probably wouldn't see much use; the prevailing locale of employment for High Desert commuters is the Inland Empire; service extension over Cajon would be considerably more appropriate than a continuation of a service that terminates in downtown L.A.

I'd sure hate to be a CHP officer assigned to San Benito County if a roundabout at CA 25's intersection with CA 156 is installed; considering the volume of commute traffic on 25 and the Valley-Monterey Peninsula/Salinas traffic on 156, with a large commercial presence, the amount of "fender benders" on any sort of roundabout will likely be staggering!  The only way a roundabout would work would be if one (or both) of the facilities were grade separated, with the roundabout serving as a distributor.  This sounds like the work of someone who has a solution (roundabout) in search of a problem (heavy traffic on both routes) without considering the particulars of the situation.  These folks (I hesistate to call them morons until they actually approve such a travesty!) need to familiarize themselves with Kingdon's treatise on the "garbage can" theory of policy formulation -- this seems like a classic example.  Unless (and forgive my paranoia here) urbanists embedded in Caltrans are attempting to punish Hollister commuters for choosing to live in such a remote exurb and thus clogging CA 25 with their presence. 

Finally, a "bypass" of I-15 over Cajon might be useful for those traffic incidents that shut down an entire carriageway -- but most of the more recent issues have concerned wildfires along side or in the exceptionally wide "median" on the south side of the summit.  Those would almost certainly close down any adjacent "alternate" routes as well.  When I was living out in Hesperia, I "pipedreamed" a potential commute solution -- excess car-carrying freight cars could be pressed into service between San Bernardino and Hesperia or Victorville via dedicated loading/unloading areas at the end points -- sort of a localized "Auto Train" concept.   UP has a bunch of those cars stored at their "mixer" yard in Mira Loma.  But getting back to the "emergency" alternate route suggested above -- all that would be necessary would be to connect the north existing end of the old Cajon Blvd. alignment to CA 138 on an alignment just west of the I-15 lanes.  North of there -- the summit section could be effectively bypassed by heading in 2 directions on 138 -- east to the Spring Valley "back road" along the BNSF tracks into central Hesperia, or west to the Phelan area before doubling back on Main Street, Bear Valley Road, or CA 18 to rejoin I-15.  Not the most direct of routes -- but they do work in a pinch (speaking as a former area resident who periodically employed both options when I-15 was a mess!). 

[nexus73]

As I recall, there was a low two digit amount of redwood trees which would need to be removed in Richardson Grove.  The final look of 101 would have been 99% of the current look.  It was a minor alignment change so large trucks would not cross the center line. 

So what if lumber shipments are not taking place?  There's this thing called FREIGHT.  Ever hear of it?  People need a lot of stuff trucked into Humboldt and Del Norte counties.  Yeah, forget the railroad,  It's been closed down for a very long time.  Either you drive it in, fly it in or boat it in.  Guess what?  Most FREIGHT is brought in by Macks, Kenworths, Freightliners and such.  Wanna run into a truck with your humongous Big Ass RV?  I....don't....think....so!  There are a ton of those gargantuan crates on 101.  FACT!!!!!

Rick

[Max Rockatansky]

As I recall, there was a low two digit amount of redwood trees which would need to be removed in Richardson Grove.  The final look of 101 would have been 99% of the current look.  It was a minor alignment change so large trucks would not cross the center line. 

So what if lumber shipments are not taking place?  There's this thing called FREIGHT.  Ever hear of it?  People need a lot of stuff trucked into Humboldt and Del Norte counties.  Yeah, forget the railroad,  It's been closed down for a very lone time.  Either you drive it in, fly it in or boat it in.  Guess what?  Most FREIGHT is brought in by Macks, Kenworths, Freightliners and such.  Wanna run into a truck with your humongous Big Ass RV?  I....don't....think....so!  There are a ton of those gargantuan crates on 101.  FACT!!!!!

Rick

Wasn't the current expressway around Richardson Grove built decades ago?  Bypassing the Grove should have been a priority from the get-go, even before the 1970s there was massive environmental protective efforts to preserve Redwoods.  If anything the current route could be promoted as something as a second Avenue of the Giants. 

[sparker]

As I recall, there was a low two digit amount of redwood trees which would need to be removed in Richardson Grove.  The final look of 101 would have been 99% of the current look.  It was a minor alignment change so large trucks would not cross the center line. 

So what if lumber shipments are not taking place?  There's this thing called FREIGHT.  Ever hear of it?  People need a lot of stuff trucked into Humboldt and Del Norte counties.  Yeah, forget the railroad,  It's been closed down for a very lone time.  Either you drive it in, fly it in or boat it in.  Guess what?  Most FREIGHT is brought in by Macks, Kenworths, Freightliners and such.  Wanna run into a truck with your humongous Big Ass RV?  I....don't....think....so!  There are a ton of those gargantuan crates on 101.  FACT!!!!!

Rick

Wasn't the current expressway around Richardson Grove built decades ago?  Bypassing the Grove should have been a priority from the get-go, even before the 1970s there was massive environmental protective efforts to preserve Redwoods.  If anything the current route could be promoted as something as a second Avenue of the Giants. 

The current expressway/freeway portion of US 101 simply "takes a break" through Richardson Grove; there have been bypass plans dating from the old Division of Highways plans from the early '60's, when the remainder of the expressway was being planned and initial construction was just getting underway.  But a real bypass has long been not only required simply because, as Rick points out, simply supplying the North Coast with the necessary goods for daily life requires appropriate facilities -- never mind the outbound lumber loads (or, today, the lack thereof).  A combination of misplaced priorities and interference from outside parties has kept such a bypass unresolved; I've driven through there probably 40+ times and have actually seen trucks come within a few inches of scraping the redwoods at roadside.  The situation there falls squarely into the ludicrous category; IMO Caltrans should finally suck it up and resolve to build something permanent even if it requires tunnels (IIRC, one of the bypass plans contained a couple of bores) or anything that doesn't screw up the general topology.  Hopefully something positive will emerge from the court's action.   

[Max Rockatansky]

As I recall, there was a low two digit amount of redwood trees which would need to be removed in Richardson Grove.  The final look of 101 would have been 99% of the current look.  It was a minor alignment change so large trucks would not cross the center line. 

So what if lumber shipments are not taking place?  There's this thing called FREIGHT.  Ever hear of it?  People need a lot of stuff trucked into Humboldt and Del Norte counties.  Yeah, forget the railroad,  It's been closed down for a very lone time.  Either you drive it in, fly it in or boat it in.  Guess what?  Most FREIGHT is brought in by Macks, Kenworths, Freightliners and such.  Wanna run into a truck with your humongous Big Ass RV?  I....don't....think....so!  There are a ton of those gargantuan crates on 101.  FACT!!!!!

Rick

Wasn't the current expressway around Richardson Grove built decades ago?  Bypassing the Grove should have been a priority from the get-go, even before the 1970s there was massive environmental protective efforts to preserve Redwoods.  If anything the current route could be promoted as something as a second Avenue of the Giants. 

The current expressway/freeway portion of US 101 simply "takes a break" through Richardson Grove; there have been bypass plans dating from the old Division of Highways plans from the early '60's, when the remainder of the expressway was being planned and initial construction was just getting underway.  But a real bypass has long been not only required simply because, as Rick points out, simply supplying the North Coast with the necessary goods for daily life requires appropriate facilities -- never mind the outbound lumber loads (or, today, the lack thereof).  A combination of misplaced priorities and interference from outside parties has kept such a bypass unresolved; I've driven through there probably 40+ times and have actually seen trucks come within a few inches of scraping the redwoods at roadside.  The situation there falls squarely into the ludicrous category; IMO Caltrans should finally suck it up and resolve to build something permanent even if it requires tunnels (IIRC, one of the bypass plans contained a couple of bores) or anything that doesn't screw up the general topology.  Hopefully something positive will emerge from the court's action.   

I have a couple pictures from 2014 of the large trucks skirting by in the grove.  It kind of makes me wonder what anyone in the Division of Highways was thinking when the issue could have been planned way back when. 

[andy3175]

What is funny is that I just posted something about SR 60 in the California at large thread..... I was thinking I'd seen one of Daniel's articles listed from a blog from a few months ago... and then it's in this month's edition as well! So now the SR 60 rework and expansion through the Badlands is both in this thread and in the California at large thread.

Regards,
Andy

www.aaroads.com

[mrsman]

Re: Normal Commute in 1988 jalopnik article

For any movie, TV show, or commercial that takes place in L.A., I do consider it a challenge to locate the locations that are shown.  L.A. is my hometown and I like to recognize things that I know.

First, I would like to say that this is not a normal commute for this route, as the drive from Culver City to Sherman Oaks is a lot worse, even in 1988 (but not as bad as today's traffic, of course).  But do keep in mind that summer would get less traffic since  UCLA and other schools are not in session, which of course is a big source of traffic.

Now the route.  His work location is on the 10700 block of McCune Ave.  This is a small side street in Palms (City of LA), near the corner of Overland and Venice.  As it sits behind Venice, looks like the south side of the street was zoned industrial, even though it is a small street.  What gave away the location is the narrowness of the street, particularly as he approached Glendon Ave, McCune is one-way and can only fit one lane of traffic.  Takes Glendon to Venice.  (THis intersection is now signalized, but wasn't back then.)  Venice to Sepulveda to the 405 Fwy north on-ramp.  The 405 of course is the majority of the video, and it was pretty smooth - all things considered.

He takes the 405 north to the 101 south and gets off at the first exit, Van Nuys Blvd.  Left on Van Nuys, left at Huston St., right on Vista del Monte Ave to the guy's house on the 4900 block.  Van Nuys/Huston now has a left turn arrow, but back then it was a simple signal.

Nothing particularly of note on this route, but interesting to see nonetheless.

[sparker]

^^^^^^^^^
In context, the entire jalopnik journey over (mostly) I-405 is quite interesting:  in 1988 the first segment of the San Diego Freeway/I-405 was 31 years old, the first section in West L.A. (Culver City to just above Sunset Blvd.) having opened as CA 7 in 1957 -- and it's been 31 more years since the article was published; the journey took place more or less right at the halfway point of the freeway's existence. 

I'm not familiar with jalopnik; would it be possible to supply a link to the work?  It would be interesting if someone sited in the L.A. area could replicate this trip under similar circumstances and see just how long it would take (or the level of frustration endured!) and compare it with the '88 "middle-of-life" look at the 405 commute.   

[mrsman]

^^^^^^^^^
In context, the entire jalopnik journey over (mostly) I-405 is quite interesting:  in 1988 the first segment of the San Diego Freeway/I-405 was 31 years old, the first section in West L.A. (Culver City to just above Sunset Blvd.) having opened as CA 7 in 1957 -- and it's been 31 more years since the article was published; the journey took place more or less right at the halfway point of the freeway's existence. 

I'm not familiar with jalopnik; would it be possible to supply a link to the work?  It would be interesting if someone sited in the L.A. area could replicate this trip under similar circumstances and see just how long it would take (or the level of frustration endured!) and compare it with the '88 "middle-of-life" look at the 405 commute.

Jalopnik is mostly a website about cars and driving.  This specific article was linked on Daniel's page as a June headline, which is why I commented on this thread.

Here is the article:

https://jalopnik.com/heres-what-a-normal-commute-from-los-angeles-was-like-i-1835525427

[bigdave]

Nice set of headlines, thanks for posting. 

The article on the 405 is bizarre, as it is hardly the worst freeway in American and IMO not even the worst freeway in LA. Again, IMO, I-110, I-10, I-5, and US 101 any where near downtown LA are more congested than the 405 for more hours of the day.

The example of the Olympics in 1984 is interesting, but the traffic volumes in that era were way lower than today.

[Max Rockatansky]

Nice set of headlines, thanks for posting. 

The article on the 405 is bizarre, as it is hardly the worst freeway in American and IMO not even the worst freeway in LA. Again, IMO, I-110, I-10, I-5, and US 101 any where near downtown LA are more congested than the 405 for more hours of the day.

The example of the Olympics in 1984 is interesting, but the traffic volumes in that era were way lower than today.

I-405 gets most of its reputation from having one of the highest traffic counts in the country and for things like Carmageddon.   I would agree that there is certainly far worse freeways in America and you can definitely make a reasonable argument for the freeways in downtown Los Angeles being worse.  My personal opinion is that the Kennedy Expressway is the worst freeway in the country.  I-405 compared to crap like the Kennedy Expressway is infinitely more we'll managed and has better carrying capacity.  I've had more trouble on the US 101 portion of the Hollywood Freeway in my own personal experience out of anything around Los Angeles.   

[sparker]

^^^^^^^^
With the exception of the San Bernardino/I-10 and Harbor/I-110 freeways, which were expanded via relatively unconventional means (the old PE ROW in the median of the former and the transit/HOV T-bridge for the latter), the original radial freeways originating downtown were always going the be the most difficult to expand, since for much of their length they traversed existing housing areas that had to be "cleaved" in order to make way for the freeways (originally 6 lanes for the most part).  Politics will likely keep I-5 from ever being expanded between the I-710 interchange and the ELA complex (they had to restripe to get what capacity they currently have!) -- and the Arroyo Seco Parkway speaks for itself (hardly a viable freeway NE of I-5, with the tunnels and the Elysian Park "cut" limiting improvements there).  And the Hollywood Freeway is hemmed in by highly variegated housing and commercial properties; again, local politics and the sheer cost of any potential improvements factor together to virtually doom any major projects; any relief is -- and likely will be for the foreseeable future -- restricted to "spot" fixes such as ramp lengthening and slip lanes where possible; structures such as the various overpasses and the Gower viaduct serve as additional limiting factors in this case.  So, as Max has astutely noted, the Hollywood Freeway is only going to get worse and worse over time -- but it's already a parking lot from about 5:30 to 9 in the morning and 2:30 to 7:30 or 8 pm in the evening, so even though the traffic count will rise, it'll seem marginal to the driver who dares to brave it at peak hours.  Unfortunately, the last time I was in the area 7 years ago the obvious alternatives -- Sunset, Temple, Beverly -- were almost as bad; commuters are already wise to them.  I suppose local street "grid patterning" is the next step -- but watch out for neighborhood complaints in Silver Lake & East Hollywood if that happens; the street department might well institute drastic "calming" if pressed to do so!

[mrsman]

^^^^^^^^
With the exception of the San Bernardino/I-10 and Harbor/I-110 freeways, which were expanded via relatively unconventional means (the old PE ROW in the median of the former and the transit/HOV T-bridge for the latter), the original radial freeways originating downtown were always going the be the most difficult to expand, since for much of their length they traversed existing housing areas that had to be "cleaved" in order to make way for the freeways (originally 6 lanes for the most part).  Politics will likely keep I-5 from ever being expanded between the I-710 interchange and the ELA complex (they had to restripe to get what capacity they currently have!) -- and the Arroyo Seco Parkway speaks for itself (hardly a viable freeway NE of I-5, with the tunnels and the Elysian Park "cut" limiting improvements there).  And the Hollywood Freeway is hemmed in by highly variegated housing and commercial properties; again, local politics and the sheer cost of any potential improvements factor together to virtually doom any major projects; any relief is -- and likely will be for the foreseeable future -- restricted to "spot" fixes such as ramp lengthening and slip lanes where possible; structures such as the various overpasses and the Gower viaduct serve as additional limiting factors in this case.  So, as Max has astutely noted, the Hollywood Freeway is only going to get worse and worse over time -- but it's already a parking lot from about 5:30 to 9 in the morning and 2:30 to 7:30 or 8 pm in the evening, so even though the traffic count will rise, it'll seem marginal to the driver who dares to brave it at peak hours.  Unfortunately, the last time I was in the area 7 years ago the obvious alternatives -- Sunset, Temple, Beverly -- were almost as bad; commuters are already wise to them.  I suppose local street "grid patterning" is the next step -- but watch out for neighborhood complaints in Silver Lake & East Hollywood if that happens; the street department might well institute drastic "calming" if pressed to do so!

From my experience, even based on my living there 20 years ago, I tend to agree.  I think the factor in determining congestion should not be how many vehicles are passing through, but rather the extent of the delays by time.  How much time would it take a driver to drive 1 mile through the section.  I-405 has a high traffic count, but it also has more lanes than the 101 Hollywood.  Most L.A. freeways are congested at rush hours and even through extended periods around rush hours and mid-days and even good parts of weekends.  But the freeways around the Downtown LA interchanges just have more merging and that leads to more congestion, even when parts of the road are open a little ways away.

The 101 Hollywood Freeway northbound just beyond the 4-level simply has too many lanes coming together. 3 lanes of mainline 101, will merge with 1 lane from Arroyo Seco and 2 lanes from Harbor to end up with 4 lanes of freeway.  This will be congested much longer than any part of the 405.

The most congested section of freeway is probably still the free lanes of 91 through Santa Ana Canyon, simply becuase (other than the toll lanes) there is no other way to make the connection.  At least with the 405, one could conceivably use Beverly Glen or Coldwater Cyn.

[sparker]

The most congested section of freeway is probably still the free lanes of 91 through Santa Ana Canyon, simply becuase (other than the toll lanes) there is no other way to make the connection.  At least with the 405, one could conceivably use Beverly Glen or Coldwater Cyn.

True -- Santa Ana Canyon (CA 91) is the worst "gauntlet" in SoCal simply due to lack of alternatives -- there's not even an original state highway alignment adjacent; the current freeway was laid atop most of it east of Yorba Linda Blvd.  The 1998 addition of traffic from the CA 241 toll road only added insult to injury.  "Pie-in-the-sky" solutions such as the long-discussed tunnel through the mountains to the south are simply that; there's just not enough money to build such a thing.  Amusingly, back about the time that CA 241 opened, there were suggestions bandied about to extend it northeast over the south end of the Chino Hills, eventually ending up out by Ontario Airport -- but those never amounted to much except speculation that quickly dissipated.  IMO -- considering the outsized growth of the Chino/Ontario area -- that concept had quite a bit of merit -- but Riverside County had little interest in adding a toll road to their inventory back then, although they've since bought into the 91 toll lanes and are adding similar lanes to I-15.   

[Mark68]

It seems that the only way to "expand" LA freeways is to expand up. Build two decks. Yes, I know there are seismic concerns, but let's face it, there are ramps at various interchanges that are positioned well above traffic below (I'm looking at you, Kellogg Hill) and have just as many potential seismic concerns.

[sparker]

It seems that the only way to "expand" LA freeways is to expand up. Build two decks. Yes, I know there are seismic concerns, but let's face it, there are ramps at various interchanges that are positioned well above traffic below (I'm looking at you, Kellogg Hill) and have just as many potential seismic concerns.

In dense areas such as that through which the Hollywood Freeway travels, opposition to double-decking would be as much a matter of visual blight and added noise (noise walls on a double-decker create essentially a "topless box", which adds to the negative visual perception).  And there are a number of active faults through the Santa Ana Canyon area (I used to live right above there in Anaheim Hills!); so for that particular instance it would likely be seismic concerns rather than anything else that would create doubts about double-decking's efficacy.  Besides, Caltrans and OCTA are presently spending multiple millions on connecting CA 241 with the toll lanes in the median of CA 91; the cost and design of any double-decking would likely be increase/complicated with the new "weaving" of the lanes and the new flyovers required to accomplish the task.  What has been proposed from time to time (one of those back about 1999, when I was still living there and the 241 interchange had just been opened the previous fall) was a second facility on a viaduct over the adjacent BNSF/Metrolink RR tracks; it would have been a 2nd 4-lane facility operated by OCTA in similar fashion to the "91 Express" lanes from west of the Yorba Linda Blvd. interchange east to where the tracks go underneath CA 91 between Green River Road and CA 71.  Like the existing express lanes, it would have been a through-put facility without any interim access points.   That idea was dropped quite quickly because (a) at the time, Riverside County, which would have to host the east end of the facility, wasn't on board -- partially because (b) it would have decimated a mobile-home park adjacent to Green River Road within Riverside County (the RR tracks bisect the park), and the owners of the park as well as a number of long-term residents loudly objected when the plan was publicly revealed.       

[mrsman]

It seems that the only way to "expand" LA freeways is to expand up. Build two decks. Yes, I know there are seismic concerns, but let's face it, there are ramps at various interchanges that are positioned well above traffic below (I'm looking at you, Kellogg Hill) and have just as many potential seismic concerns.

In dense areas such as that through which the Hollywood Freeway travels, opposition to double-decking would be as much a matter of visual blight and added noise (noise walls on a double-decker create essentially a "topless box", which adds to the negative visual perception).  And there are a number of active faults through the Santa Ana Canyon area (I used to live right above there in Anaheim Hills!); so for that particular instance it would likely be seismic concerns rather than anything else that would create doubts about double-decking's efficacy.  Besides, Caltrans and OCTA are presently spending multiple millions on connecting CA 241 with the toll lanes in the median of CA 91; the cost and design of any double-decking would likely be increase/complicated with the new "weaving" of the lanes and the new flyovers required to accomplish the task.  What has been proposed from time to time (one of those back about 1999, when I was still living there and the 241 interchange had just been opened the previous fall) was a second facility on a viaduct over the adjacent BNSF/Metrolink RR tracks; it would have been a 2nd 4-lane facility operated by OCTA in similar fashion to the "91 Express" lanes from west of the Yorba Linda Blvd. interchange east to where the tracks go underneath CA 91 between Green River Road and CA 71.  Like the existing express lanes, it would have been a through-put facility without any interim access points.   That idea was dropped quite quickly because (a) at the time, Riverside County, which would have to host the east end of the facility, wasn't on board -- partially because (b) it would have decimated a mobile-home park adjacent to Green River Road within Riverside County (the RR tracks bisect the park), and the owners of the park as well as a number of long-term residents loudly objected when the plan was publicly revealed.     

For anyone old enough to remember the 1989 Loma Prieta earthquake, double decking is a no-go.  The images of the collapsed Bay Bridge and Nimitz Freeway are still in my head.

While it's true that any bridge structure would have some level of seismic concern, a double decking means that the concern is over a long stretch and not just at a single point.  So psychologically, it is OK to cross under a bridge, perpendicularly, it is far more concerning to drive under another highway for miles.

Even in areas that aren't seismically active, there are concerns over the care of some viaducts.  The Brooklyn-Queens Expressway that is a double deck comes to mind.  There are plans to make repairs.

[RoadMaster09]

About Richardson Grove, why is a bypass deemed unfeasible? I don't think it is at all; it would need a tunnel though to keep the elevation constant but otherwise it isn't any more difficult than other completed sections of US 101. We are also only talking about 4 miles of freeway, half of which is on bridges or in a tunnel (which would likely be about 3/4 mile to 1 mile in length). Bonus: eliminating trucks completely (not just oversized trucks) from the park. There is enough room as well ahead of both terminals for parking areas for HAZMAT trucks to call for escorts.

[sparker]

About Richardson Grove, why is a bypass deemed unfeasible? I don't think it is at all; it would need a tunnel though to keep the elevation constant but otherwise it isn't any more difficult than other completed sections of US 101. We are also only talking about 4 miles of freeway, half of which is on bridges or in a tunnel (which would likely be about 3/4 mile to 1 mile in length). Bonus: eliminating trucks completely (not just oversized trucks) from the park. There is enough room as well ahead of both terminals for parking areas for HAZMAT trucks to call for escorts.

Physically, a bypass would be a difficult project considering the area's topology -- but not impossible.  The opposition has come from any number of the usual suspects who generically oppose highway capacity increases, particularly in areas considered relatively "pristine".  The Grove isn't their only "cause"; they've managed to derail a planned bypass several miles south on the other 2-lane segment north of Leggett (which, if truth is told, would be an even more difficult project than Richardson Grove!).     

[bigdave]

It seems that the only way to "expand" LA freeways is to expand up. Build two decks. Yes, I know there are seismic concerns, but let's face it, there are ramps at various interchanges that are positioned well above traffic below (I'm looking at you, Kellogg Hill) and have just as many potential seismic concerns.

Apparently seismic concerns were somehow addressed when HOV lanes were erected above the Harbor Freeway.

[sparker]

It seems that the only way to "expand" LA freeways is to expand up. Build two decks. Yes, I know there are seismic concerns, but let's face it, there are ramps at various interchanges that are positioned well above traffic below (I'm looking at you, Kellogg Hill) and have just as many potential seismic concerns.

Apparently seismic concerns were somehow addressed when HOV lanes were erected above the Harbor Freeway.

The design/construction of the overhead lanes was done with seismic resistance in mind (I wonder how the embedded sensors reacted to yesterday's 6.4 out in the desert!); also, it wasn't 2 decks suspended over a surface facility like the Bay Area ones that failed in the '89 Loma Prieta quake -- and it wasn't built on slushy landfill that wobbled like a bowl of Jello.  All that notwithstanding -- today would be a good time for Caltrans to shut down that structure and "fine-tooth-comb" it for cracks or other signs of stress -- if they aren't doing so already!