All is illustrated in the following images. To provide context, I have also included a few photographs of the landscape before the blaze. Cajon Pass, indeed most all of the western United States, has endured countless blazes in the past and will suffer countless more in the future. But the earth is resilient; it will be here long after we are gone.
For reference, here is the same location immediately before the fire – August 2016.
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The Blue Cut Fire started on August 16, 2016, at 10:36 a.m. along old U.S. 66, north of Kenwood Avenue and west of Interstate 15, and quickly spread up Cajon Creek toward Blue Cut and the San Gabriel Mountains. At the peak of the blaze, 2,684 firemen from across the United States were in action. By 3:00 p.m., less than six hours after the initial burn, the blaze had spread north and east to over 5,500 acres, forcing evacuations and the closure of the BNSF and UP lines, as well as California 138 and Interstate 15. By Thursday, August 18, the fire had grown to over 31,600 acres and forced the evacuation of over 82,000 people. On Monday, August 22, fire officials said they had the fire 89 percent contained. The damaged area had grown to 37,000 acres. Officials declared the wildfire fully contained Tuesday, August 23. The blaze destroyed an estimated 105 homes and 213 other structures in San Bernardino County and now ranks as the 20th most destructive wildfire in California history.
Notice also the proximity of the fire line to the dwelling nestled in the trees. Can you imagine the anxiety of the property owners? I can, because a few years ago, a wildfire came within a half mile of my house. The firefighters who stopped the blaze are now my heroes.
His house is located in the middle of the San Gabriel National Forest, the federal protectorate that keeps Cajon Pass safe from the metastasizing development that has overrun the Los Angeles Basin. He told me that the property had been in his family before the national forest was created. As long the property stayed in his family, it would be a small island within the National Forest.
His property was fenced. Inside were three extremely friendly Golden Retrievers who exploded with happiness when I took my dog Bear, aka Mighty Dog, out of my rented Tacoma. Bear walked over slowly and peed on the fence. The Retrievers began peeing on the fence. If I were a dog, I would also have peed on the fence.
Notice the flat valley in the background of the above two images – the San Andreas fault. The BNSF triple-track mainline, the UP Palmdale cut-off, Interstate 15, old US 66, as well as several high pressure gas lines and high-voltage electric lines, all cross the fault in the same location, which is called Blue Cut. When the fault slips again, there will be some serious consequences.The burned trees on the mountainside speak for themselves.
UP Passing UP at Same Location |
BNSF Bare Table Rolling Through the Destruction at Blue Cut Looking Back Toward San Bernardino |
UP’s Palmdale Cut-off runs on a higher grade between photographer and train. Notice how most of the trees in the wash survived the blaze, though some did not. Beyond the stream is old Route 66. Everything around the highway and beyond was completely burned.
If you look closely, you will see several of the high voltage electric lines running through and across the canyon. The huge metal towers supporting the lines all escaped damage in the blaze, though I understand that some towers are being re-supported at ground level because of severe erosion.
The policy of banning fires in national parks and forests began in 1886 at Yellowstone National Park and was incorporated in the National Parks Act of 1916. Fire suppression was based on claims that fire damaged trees, killed seedlings, promoted floods and erosion and destroyed shelter for birds and animals.Early researchers in the South contested these claims, pointing out that controlled burns helped establish pine trees, suppressed hardwood competitors, reduced hazardous underbrush accumulations and controlled forest diseases. So during the 1920’s to the 1940’s, the Forest Service began to realize that, at least in the South, controlled burning was beneficial.
In 1955, the McGee Fire burned west of Kings Canyon National Park and in just a few hours consumed over 13,000 acres of brush and forest and threatened the Grant Grove of giant sequoias, which led a number of scientists to question the old paradigm of fire suppression and conclude that in the sequoia-conifer forests, periodic fire is valuable, because it allows germination and survival of sequoia seedlings, as well as clearing out the underbrush that had fueled the McGee Fire.
Same Location |
The lower end of Cajon pass consists of a huge alluvial deposit two miles wide, about 5 miles above Devore, the gorge through which is know as Blue Cut. Much of the rock is schist, a major part of the terrain southwest of the gorge. Schist is formed generally by mud and silt under extreme pressure and temperature, often containing large crystals that reflect light. At Blue Cut, the rock appears greenish to my eyes, so I do not understand how the name derived.
The image below looks east into Blue Cut. Old Route 66 runs beside a huge slice in the schist, which originally flowed down from the mountains as mud and silt, much like the deposits washed down during the winter rains of 2016-17 – except on a much grander scale. Here a UP manifest in dynamic breaking is overtaking a BNSF manifest, also in dynamics, on the triple-track mainline to the right.
Same Location -- Different Train |
Eastbound BNSF stacks on the triple-track mainline pass a westbound UP merchandise freight on the Palmdale Cut-off in Cleghorn Canyon.
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Every tree in Cajon Creek has been burned. All the grass and bushes on the ridge above the trains have been burned. The second ridge in the middle of the image has also been burned. Virtually nothing is left. Only the peaks of the San Gabriel Mountains in the background escaped the devastation.
Eastbound UP Merchandise Freight Climbing the Grade in Cleghorn Canyon
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Same Location -- Two Weeks Before Fire |
UP Autoracks and Stacks in Cleghorn Canyon |
East of old U.S. 66 and I-15, the Cleghorn Ridge Trail climbs high into the peaks and ends at Silverwood Lake State Recreation Area. I have driven portions in my Jeep Wrangler but have never taken the 2 ½ to 3 hours necessary to reach the lake. Several of the images in this post, including the ones above and below, were taken from the trail – high above the canyon and rail lines.
Eastbound BNSF Oil Train in Sullivan's Curve |
When we emerged on the west side of the highway, we then crossed Cajon Creek. Every tree along the stream was dead, all trunks blackened by the Blue Cut Fire. We passed the remains of an old house burned to the ground, a structure that the firefighters could not save. Several black fence posts still stood upright. On one hung a sign which said: “NO TRESSPASSING.”
The trail followed the stream a short distance through the sand, then turned south and began a slow, twisting climb up low hills. Around us were the burnt remains of creosote bushes and scrubby trees. But beneath these ruined hulks, green grass has started to sprout from the sand and clay, giving the countryside the strange appearance of new life bursting through the remains of the dead, like baby spiders eating their way out of innards of their dying mother.
UP 8644 West (an SD70ACe) Approaches Sullivan’s Curve Through the Remains of the Blue Cut Fire
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The trail continued down to the dry bed of a stream that fed into Cajon Creek. The sand was especially deep, and Bear and I trudged ahead until we came to a culvert that led beneath the double-tracked BNSF mainline. The tunnel was round, bottomed with smooth pebbles and more sand. When we emerged from the south end, the trail turned steeply uphill, leading us to a crossing of the UP line (the old SP Palmdale Cut-off). Dog and human continued upgrade until we found a spot above both the UP and BNSF lines in the middle of the curve.
The wind was hard out of the north and brisk, and the temperature was about 45 degrees. As is his wont, Bear looked at me with plaintive eyes, as if to say, “It is going to be cold standing up here in the wind. Can we go back to the rented Tacoma?”
Bear knows better than to ask that question. So he hunkered down in the sand between two burned bushes and waited patiently while the old man set up his tripod. Bear has learned that whenever I have a camera, a train will soon appear. His ears were perked. Soon we heard a westbound in dynamic breaks, rolling downgrade. I turned the camera to the north and took the image below.
Most of the railroad traffic Bear and I saw that afternoon was Union Pacific, both on BNSF tracks and on the Palmdale Cut-off. By and large, the engines were clean and sleek, a far cry from the filthy units I am accustomed to seeing on UP coal trains around Kansas City.
In this image, a loaded, UP coal train has just crested the summit and is beginning the descent through Cajon Pass. On the Palmdale Cut-off, the train is moving about five miles per hour and will pick up little speed until it turns south past the Mormon Rocks. Immediately beyond the train is the construction of new Highway 138. If you look closely, you can see small portions of the old road twisting and turning through the sand. In the left of the picture is one set of high voltage electric lines crossing the burned hills into the valley. If you know where to look, you can also see I-15 and the railroad tracks at the bottom of the valley.
For me, this location produces the most dramatic view of Cajon Pass, in part because it illustrates the dynamic nature of the faults moving through the valley. Although you cannot see it, the San Andreas Fault runs at the base of the snow-capped San Gabriel Mountains, providing the line of demarcation with the San Bernardino Mountains to the east – the western edge of which can be seen in the far left of this image. This land is constantly moving, turning, deforming itself in a hundred different directions like a child’s sandbox after a heavy rain. The following excerpt from the abstract of the Ph. D. dissertation of R. J. Weldon, which can be found at http://resolver.caltech.edu/CaltechETD:etd-08302006-135307, gives a succinct description of the forces which have shaped and continue to shape Cajon Pass:
"The geology in Cajon Pass, southern California, provides a detailed record of strike slip activity on the San Andreas fault, compressional deformation associated with the uplift of the central Transverse Ranges and an excellent Cenozoic record of syntectonic sedimentation. . . . Tectonic deformation and sedimentation styles varied through time, reflecting the evolution of the San Andreas fault zone within the Pacific - North American plate boundary. Four independent measurements of the slip rate yield an average of 24.5 ± 3.5 mm/yr. The similarity of the four values, which span different intervals of time up to 14,400 years ago, suggest that the slip rate has been constant during this period. An excavation across the San Andreas fault provided some constraints on the timing of paleoearthquakes. Coupled with the historic record, this investigation indicates that the last earthquake associated with rupture on the fault in Cajon Pass occurred around 1700 AD. At least 2 earthquakes caused rupture on the San Andreas fault after 1290 AD and perhaps 6 earthquakes are recorded in the thousand year period before European settlement of southern California in the 1770s. Downcutting and erosion into the western San Bernardino Mountains, during the last 700,000 years, has created Cajon Pass as it exists today. The downcutting was punctuated by at least four pulses of channel aggradation that provide stratigraphic markers throughout the area. They are dated at 0.5 ± 0.1 million, 55,000 ± 10,000, 17,000 to 6,000, and 2000 to 300 years ago. These aggradational periods were caused by order of magnitude increases in sediment production associated with changes in the climate from relatively wet to dry conditions.”
Thus, the incredible landscape shown in these images resulted from the movement of the North American plate past the Pacific Plate, uplifting the terrain to enormous heights, followed by hundreds of thousands of years of erosion, combined with four separate events of massive sedimentary wash down the peaks, creating huge alluvial despots that eventually turned into schist, such as the rock at Blue Cut. I also suspect that erosion in Cajon Pass has been aided greatly over the eons by conflagrations such as the Blue Cut Fire. The image above shows a completely barren landscape from which silt and sediment can easily wash down into the valleys.
Shortly before reaching the top of Cajon Pass, trains running south turn back toward the east. This same path was followed by the Blue Cut Fire, which reached a small portion of the high desert here. No structures were damaged, however, and firefighters controlled the blaze shortly past the top of the hill. The image below was taken on a morning in late April, 2017, when fog was blowing up Cajon Pass from the Los Angeles Basin and spilling onto the high desert. The peak of Mount San Antonio (or Mount Baldy, as many locals call it) is just visible in the upper left. The train is cresting the summit, and the photographer is standing approximately where the fire was contained.
Below, BNSF 6613 East (an ES44C4) has crested the summit of Cajon Pass and is headed across the high desert toward Hesperia and Barstow. The vegetation here is what Cajon Pass looked like before the Blue Cut Fire. In years to come, the pass will look this way again. For now, however, the desert and mountain ridges need time to heal, to regenerate, to continue the ageless cycle of plate movement along the San Andreas fault and erosion of the uplifted mountains.
To see all my posts, go to waltersrail.com.
Westbound BNSF stacks roll downgrade at the entrance to Sullivan’s Curve, while Bear the Mighty Dog crouches to avoid the wind.
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Eastbound UP stacks climbing the grade in Sullivan’s Curve on BNSF track. In the foreground are the Palmdale Cutoff and passing siding.
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Eastbound UP Stacks in Sullivan’s Curve |
The Blue Cut Fire roared straight up the pass, following both the tracks and I-15, which climbs the ridge on a much steeper grade and does not turn south but rather north to the summit. The fire destroyed an old restaurant and gas station at the top of the Interstate, but firefighters managed to control the conflagration before it spread into populated areas in the high desert near Hesperia.
If you have a four-wheel drive vehicle and knowledge of the local roads, you can navigate through the desert to the hill that overlooks the tracks approaching the summit. A word of warning: The following images were taken from a minimum maintenance road directly beneath the twin high voltage towers and lines that run down the pass to the Los Angeles Basin. These lines crackle and pop all day like a thousand frenzied insects and create a static field that can make the hair on your arms and neck stand up. I find the experience disconcerting but not uncomfortable enough to sabotage photography.
When the following images were taken, the State of California was widening and straightening State Highway 138 between I-15 and the summit of Cajon Pass. The old road was the most narrow and winding imaginable and saw significant traffic, including heavy trucks. At one time, California’s hills and valleys were criss-crossed with such death traps. Over the years, most have been eliminated. (A few still exist around Tehachapi Pass, such as Caliente-Bodfish Road.) Until recently, State Highway 138, winding up and down, left and right, curving and dipping, with no possible room for passing, allowed easy access to the San Bernardino National Forest on several minimum maintenance roads to multiple locations where one could take good shots of trains ascending and descending Cajon Pass. Also, one could pull off the road at the top of the grade and take excellent shots of trains climbing to the summit and turning east again. All this may be gone when the new construction is completed.
Union Pacific Coal Headed Downgrade Beneath San Gabriel Mountains
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UP Meets BNSF Across the Tortured Landscape of Cajon Pass
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"The geology in Cajon Pass, southern California, provides a detailed record of strike slip activity on the San Andreas fault, compressional deformation associated with the uplift of the central Transverse Ranges and an excellent Cenozoic record of syntectonic sedimentation. . . . Tectonic deformation and sedimentation styles varied through time, reflecting the evolution of the San Andreas fault zone within the Pacific - North American plate boundary. Four independent measurements of the slip rate yield an average of 24.5 ± 3.5 mm/yr. The similarity of the four values, which span different intervals of time up to 14,400 years ago, suggest that the slip rate has been constant during this period. An excavation across the San Andreas fault provided some constraints on the timing of paleoearthquakes. Coupled with the historic record, this investigation indicates that the last earthquake associated with rupture on the fault in Cajon Pass occurred around 1700 AD. At least 2 earthquakes caused rupture on the San Andreas fault after 1290 AD and perhaps 6 earthquakes are recorded in the thousand year period before European settlement of southern California in the 1770s. Downcutting and erosion into the western San Bernardino Mountains, during the last 700,000 years, has created Cajon Pass as it exists today. The downcutting was punctuated by at least four pulses of channel aggradation that provide stratigraphic markers throughout the area. They are dated at 0.5 ± 0.1 million, 55,000 ± 10,000, 17,000 to 6,000, and 2000 to 300 years ago. These aggradational periods were caused by order of magnitude increases in sediment production associated with changes in the climate from relatively wet to dry conditions.”
BNSF meets BNSF Below Summit of Cajon Pass
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Eight units lead BNSF stacks past the beginning of the descent through Cajon Pass.
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Summit
BNSF Stacks at Summit |
UP Coal Meets BNSF Grain at Summit |
To see all my posts, go to waltersrail.com.
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