Tunnel #2: (Bridge Hunter; HAER; Satellite)
I learned a couple of days ago that BNSF daylighted the only tunnel in Nebraska. Yesterday I came across these comments on a post:
Bentstrider Francesco Nittoni There was also a tunnel that used to exist in the Cajon Pass on the BNSF/UP trackage in that area. The entire tunnel section was "daylighted"/demolished in 2007 or 08 due to the high volume of double stacks running through there.
Interestingly enough, I do recall double stack intermodals fitting through there. But I'm guessing the railroads didn't want to risk any over clearance strikes.
Allan Gilbert Stack trains have been going through the tunnels (plural) for almost 40 years. They were daylighted to accommodate a third track through the pass. In the process of uncovering the longer of the two, the pressure on the sides once the top was uncovered cause the arch of the roof to buckle and crack. The last train through reported concrete and dirt falling on their locomotive.
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Photo from HAER CA-2259-E-1 from ca3521OVERALL VIEW OF APPROACH TO EAST PORTAL OF TUNNEL, SHOWING ACCESS ROAD AND UNION PACIFIC TRACK AT RIGHT. [5] - Burlington Northern Santa Fe Railroad, Cajon Subdivision, Tunnel No. 2, Between Cajon Summit and Keenbrook, Devore, San Bernardino County, CA
[The track on the right is UP's track.]
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BNSF has demonstrated how far earth moving technology has advanced from the early 20th Century to the early 21st Century. Today we can literally move mountains.
This topo map provides some "before" information. The track near the bottom was Santa Fe's original route over the pass. If you look at the grade graph at the bottom of this page, you will see that the ruling grade for eastbound trains was 3%. (Note the "Fun Fact" on the map that it cost BNSF $90m to add the third track, which is why the tunnels were daylighted.) So in 1913 Santa Fe built the track with two tunnels to reduce the ruling grade to 2.2%. Now BNSF/Santa Fe runs their trains left-handed across the pass so that the westbound trains go down the original steeper route while the eastbounds climb the 2.2% grade. Of course, the second track not only reduced the grade that had to be climbed by trains, it increased the capacity. I'm sure that the increased capacity of a second track was important because UP has trackage rights over the Santa Fe route to just past Barstow for their trains headed to Las Vegas and to the East. The top track is UP's track, but it goes to Mojave instead of to the East.
The east tunnel is tunnel #1.
This topo map provides some "before" information. The track near the bottom was Santa Fe's original route over the pass. If you look at the grade graph at the bottom of this page, you will see that the ruling grade for eastbound trains was 3%. (Note the "Fun Fact" on the map that it cost BNSF $90m to add the third track, which is why the tunnels were daylighted.) So in 1913 Santa Fe built the track with two tunnels to reduce the ruling grade to 2.2%. Now BNSF/Santa Fe runs their trains left-handed across the pass so that the westbound trains go down the original steeper route while the eastbounds climb the 2.2% grade. Of course, the second track not only reduced the grade that had to be climbed by trains, it increased the capacity. I'm sure that the increased capacity of a second track was important because UP has trackage rights over the Santa Fe route to just past Barstow for their trains headed to Las Vegas and to the East. The top track is UP's track, but it goes to Mojave instead of to the East.
The east tunnel is tunnel #1.
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| 1996 Cajon Quadrangle @ 1:24,000 |
We can use a contemporary satellite image for an "after" view.
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| Satellite |
Instead of browsing the HAER photos, I recommend the photos on this page because it shows before and after views of each portal. For example, this is what the above HAER view looked like after daylighting. The page then has many more "before" photos.
Since the Cajon Pass is a popular railfan spot, the construction was well documented.
The instructions are slightly wrong. To access a page of about 100 photos you should click on the link in the middle column. Additional rows link to other albums.
This photo in that collection of 896 photos shows the intermediate stage that reduced the pressure on the top of the arch and allowed it to buckle upwards as mentioned in Allan's comment at the top of this page.
The construction interval of 2007-2008 is in the range of years covered by Global Earth images. These images are looking south so Tunnel #2 is on the right. The reason for not using the normal view to the north is that the mountain peak hid Tunnel #2.
The construction interval of 2007-2008 is in the range of years covered by Global Earth images. These images are looking south so Tunnel #2 is on the right. The reason for not using the normal view to the north is that the mountain peak hid Tunnel #2.
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| Apr 2007 |
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| Jun 2009 |
The "black spots" are where they used shotcrete to make retaining walls.
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| Satellite |
A couple of comments about the retaining walls from a Trainorders thread:
Date: 04/25/08 16:04
Re: Cajon Pass Tunnels - Over and Out
Author: TopcoatSmith
The material is fairly solid (Cima Scrambler knows a more complete description of it) and since the area doesn't receive a large amount of rain it generally stays put.
It takes a bit of breakout force for the excavators to load the stuff up, dozers with rippers being used to assist in that process.
The actual slope reinforcement involves drilling 40 feet into the slope at a slight downward angle (you can see the two rows of holes in the first pic), a piece of coated rebar is inserted and shotcrete is pumped into the holes and over the wire mesh covering the slope. Drain holes are drilled at an opposite angle and a preforated pipe is installed. There are numerous places along other slopes where water trickles out from the layers or rock and soil (Cozy Dell, the cut between Cajon and Sullivan's) but it's not a large amount, little more than enough to wet the surrounding earth. The shotcreted slope isn't going to fail or fall any time soon, even in an El Nino year.
They're also a substantial distance back from the track centers.
The only slope failure I know of is the minor slipout on the north side of where tunnel 2 was, looks like a lens of clay-like material but I am no expert on that.
Ames is doing some of the Sunset Route double tracking for UPee, that's wher some of them are headed next along with those that have already gone.
TCS - new angles abound, the trick now is to find them with trains in them
It takes a bit of breakout force for the excavators to load the stuff up, dozers with rippers being used to assist in that process.
The actual slope reinforcement involves drilling 40 feet into the slope at a slight downward angle (you can see the two rows of holes in the first pic), a piece of coated rebar is inserted and shotcrete is pumped into the holes and over the wire mesh covering the slope. Drain holes are drilled at an opposite angle and a preforated pipe is installed. There are numerous places along other slopes where water trickles out from the layers or rock and soil (Cozy Dell, the cut between Cajon and Sullivan's) but it's not a large amount, little more than enough to wet the surrounding earth. The shotcreted slope isn't going to fail or fall any time soon, even in an El Nino year.
They're also a substantial distance back from the track centers.
The only slope failure I know of is the minor slipout on the north side of where tunnel 2 was, looks like a lens of clay-like material but I am no expert on that.
Ames is doing some of the Sunset Route double tracking for UPee, that's wher some of them are headed next along with those that have already gone.
TCS - new angles abound, the trick now is to find them with trains in them
Date: 04/25/08 22:42
Re: Cajon Pass Tunnels - Over and Out
Author: CimaScrambler
What, you mean my mini-treatise on How Cajon Became Cajon?
http://www.trainorders.com/discussion/read.php?1,1516455,1516888#msg-1516888
http://www.trainorders.com/discussion/read.php?1,1516455,1516888#msg-1516888
[search for "CimaScrambler"]
short answer: It is actually a soft sandstone that can be subject to becoming a landslide given enough di-hydrogen monoxide. Great dry strength, not so great when it's all wet.
- Kit (I said I was going to see the tunnels, but she said I would not know that from a hole in the ground.) (snigger)
Kit Courter
Torrance, CA
LunarLight Photography
short answer: It is actually a soft sandstone that can be subject to becoming a landslide given enough di-hydrogen monoxide. Great dry strength, not so great when it's all wet.
- Kit (I said I was going to see the tunnels, but she said I would not know that from a hole in the ground.) (snigger)
Kit Courter
Torrance, CA
LunarLight Photography
Update:
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| Gordon Edwards posted Tunnel No. 2, Cajon Pass (2005), gone now. Neopan400 Dennis DeBruler West Portal |
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| Gordon Edwards posted End of the tunnel-2007 |
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| John B Mobley posted Cajon tunnel 1. David Thompson Cajon Tunnel No. 1 379.0 ft. No. 2 467.5 ft. both on a 2.20 grade (Operations Santa Fe by M. Armitage Pg. 161) |
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| Brendon Hilton commented on John's post When i handed the camera to the gang foreman to take this pic, he looked at me like - did these bozos really stop my work train for a photo op? lol...yup |
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| Brian M. Taggart commented on John's post I shot this from my work train on UP's Mojave sub on December 23, 2007. |
Bruce Johnson posted two photos with the comment: "Picture of an old tunnel in Cajon Pass north of San Bernadino, CA with present-day image after extensive reworking of the grade."
Bruce Johnson shared
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