Oddly it doesn't seem we had a catch all thread for I-580...weird...
I made some substantial updates to the Interstate 580 blog on Gribblenation. The blog now features articles from the California Highways & Public Works and when the Division of Highways petitioned the AASHO to truncate US Route 50 from San Francisco to Sacramento. Unfortunately I didn't find anything regarding when Interstate 5 West was nixed in the AASHTO Database but I did manage to grab the photo of the I-5W shield in a California Highways & Public Works. The blog also now features the entire route of Interstate 580 in addition to the pedestrian lane on the Richmond-San Rafael Bridge.
https://www.gribblenation.org/2019/03/interstate-580-from-i-205-west-to-ca-13.html
Thanks for posting this history. I've traveled maybe 30% of this route, so I definitely need to check it out again.
In the section where you describe the 1938 realignment through Altamont Pass, that "Western Pacific" arch bridge is a rare example where you can still see that former company name. Western Pacific was acquired by Union Pacific in 1982, and UP promptly went about "re-branding" the entire rail line (Oakland to Salt Lake City) to show the Union Pacific name, removing most WP line-side signs and logos along the route.
As for that pedestrian walkway across the bridge, now there's a spot to get in one's daily steps. That would be a real haul; bring sunscreen (and some kind of ear protection from the steady drone of adjacent traffic).
I would like to try to run the Richmond-San Rafael Bridge perhaps some time this year. The primary issue I see is finding where the hell to park since the trail maps aren't exactly great:
https://baytrail.org/get-on-the-trail/map-by-number/richmond-san-rafael-bridge-2/
I've done the Golden Gate Bridge a couple times so it would be cool to add the Richmond-San Rafael Bridge and the eastern Bay Bridge segment as well.
Regarding the Western Pacific overpass I've heard some interesting conjecture on how that might be reused. I don't know if there has been anything new regarding whether any of those concepts might become reality.
Quote from: Max Rockatansky on February 26, 2021, 10:31:18 PM
Regarding the Western Pacific overpass I've heard some interesting conjecture on how that might be reused. I don't know if there has been anything new regarding whether any of those concepts might become reality.
It is still in service; the UP uses that as a freight route to the Bay Area, and ACE (Altamont Commuter Express) trains use it. I have ridden over it on an Amtrak detour, though I don't have pics handy.
I-580 is one of only two routes where the post miles run backwards, meaning they increase from east to west. This is a leftover legacy from its designation as I-5W. The backwards postmiles were also carried over when I-580 was extended over CA-17 in 1983.
Here are the pics from March 15, 2013, on Amtrak's detouring Coast Starlight #11 headed to Los Angeles. The train is on the ex-WP line noted above, heading compass "east" at this point. Both views face "north" to I-580, the location is roughly halfway between exits 59 and 63.
1. Just east of the arch bridge, this shows the divided highway segment. The abandoned SP Railroad grade can be seen along with part of a tunnel entrance.
(https://live.staticflickr.com/65535/50986670841_9ca094b54a_z.jpg)
2. This also shows the divided highway segment, with the abandoned SP grade in the foreground.
(https://live.staticflickr.com/65535/50986778487_d606bd9e2d_z.jpg)
Is there any way to fix the merge from Westbound 24 onto 580. Man that merge sucks, especially when its backed up from cars heading to Eastbound 80
Quote from: jrouse on February 27, 2021, 12:54:35 PM
I-580 is one of only two routes where the post miles run backwards, meaning they increase from east to west. This is a leftover legacy from its designation as I-5W. The backwards postmiles were also carried over when I-580 was extended over CA-17 in 1983.
Not sure where CA-18 fits into there (assuming you were referring above to CA-72 using the old US 101 postmiles as being the other backwards route). Technically CA-18's western end is at the 210 freeway, and there is where the postmiles start at 0. But where it terminates at CA-138 in LA County, CA-18 is much farther west than where it started, and as it runs due west across the high desert toward that terminus, its postmiles increase from east to west.
Quote from: jrouse on February 27, 2021, 12:54:35 PM
I-580 is one of only two routes where the post miles run backwards, meaning they increase from east to west. This is a leftover legacy from its designation as I-5W. The backwards postmiles were also carried over when I-580 was extended over CA-17 in 1983.
Actually, that's wrong. There are five routes where the post miles run in the other direction: Route 71, Route 153, Route 282, I-580, and I-780. All are artifacts of their being much longer routes.
Quote from: Occidental Tourist on February 28, 2021, 12:40:55 AM
Not sure where CA-18 fits into there (assuming you were referring above to CA-72 using the old US 101 postmiles as being the other backwards route). Technically CA-18's western end is at the 210 freeway, and there is where the postmiles start at 0. But where it terminates at CA-138 in LA County, CA-18 is much farther west than where it started, and as it runs due west across the high desert toward that terminus, its postmiles increase from east to west.
Remember that Route 18 originally ran along what was Route 91, starting in Artesia, and was based on a south to north routing. In 1964 it was truncated to start at Route 10 (which is the starting point on the books), and the numbering makes sense when viewed as S to N. The state highways don't follow a strict odd/even on N/S vs E/W.
Quote from: jander on February 27, 2021, 09:21:43 PM
Is there any way to fix the merge from Westbound 24 onto 580. Man that merge sucks, especially when its backed up from cars heading to Eastbound 80
Agreed 100%, and I'm always surprised when I'm there just how popular the 580 "through movement" is. Separating 24 -> 80 west traffic from the weaving zone would work well, but I would guess it just doesn't fit anywhere in the footprint of the area.
Quote from: citrus on March 03, 2021, 11:42:01 AM
Quote from: jander on February 27, 2021, 09:21:43 PM
Is there any way to fix the merge from Westbound 24 onto 580. Man that merge sucks, especially when its backed up from cars heading to Eastbound 80
Agreed 100%, and I'm always surprised when I'm there just how popular the 580 "through movement" is. Separating 24 -> 80 west traffic from the weaving zone would work well, but I would guess it just doesn't fit anywhere in the footprint of the area.
That one is definitely bad with lots of weaving and last-minute lane dives, but the one drives me nuts is the 580/238 interchange with all the truck maneuvers. It's almost as if the design team never went out in the field or did any research on traffic patterns. When that interchange was reconstructed 30 years ago replacing the last vestiges of US50 through Castro Valley, the 238 "ramps" should have connected to 580 from the east on the outside of the 580 through lanes. Because trucks are not permitted on 580 through Oakland (except under very limited circumstances) all trucks going westbound must now cut over to the left side to continue on 238 and vice-versa going east which creates all kinds of crazy driving moves by others trying to get around slower-moving trucks in the "fast" lanes. The "marginal cost" of doing it correctly back then would have been far less than what would be a corrective measure now, ala the 5/14/405 truck bypass layout. A totally lost opportunity . . .