Friday, December 6, 2019

A Brief Tour of Tehachapi

Writing about Tehachapi is like writing about the War Between the States.  What can you say that has not already been said?  Still, people keep churning out new books about Vicksburg and Manassas and Shiloh and Antietam, as though no one has ever heard those words before.  Given the current state of education, that may in fact be the case.  I do not know. 

What I do know is that Tehachapi, indeed all of California, is so geologically active that in a human lifetime it is possible to see the earth move -- one earthquake at a time.  And when the earth moves, it explodes; it sounds like a bomb.  It is a bomb.  I have heard this sound more than once in my life and hope never to hear it again.

For all this, the movements of our planet are small and discrete in geological terms, five feet or so at a time.  A really big temblor, such as San Francisco in 1906, may move the ground twenty feet.  Considering that the tallest peak in the Sierra Nevada is Mount Whitney, 14,505 feet and still growing, the movements we witness in our lifetimes are rather puny.  And while mountains are rising earthquake by earthquake, the erosional forces of rain and wind are tearing them down, rolling boulders as large as human heads down the slopes to collect over millions of years as alluvial fans.  Eventually, the mountains disappear, and the alluvial fans are buried beneath thousands of feet of detritus and, under enormous heat and pressure, are transformed into the rock that eventually rises again to form another mountain chain that, eventually, erodes down to nothing, to start the process over again and again. 

How long does this take?  Mount Everest is 29,029 feet tall.  Geologists have studied rates of erosion in the Himalayas,  and even low rates of erosion are around 0.1 millimeter per year.  If Everest were to erode at 0.1 millimeter per year, it would disappear (assuming that it were not still rising, which it is) in 88,480,000 years.  This may sound like a long time, but the earth is estimated to be 4.5 billion years old.  Thus, if everything else remained static, which it does not, you could erode away Mount Everest about 50 times since the beginning of the planet.

Moreover, if a mountain range jumps 10 feet in an earthquake, it will take an awfully long time to erode back to its previous height, assuming the range does not jump again, which it will.  This is why earthquakes win out over erosion.  Mountains disappear only after they stop rising.

Since humans have been on the earth about 200,000 years, it is reasonable to say that the species, as a totality, has never seen a mountain ridge rise from the ground.  Nor has it seen one erode away.  In addition, since our planet has seen at least five major extinctions (some say six) during its troubled history, including the Cretaceous–Paleogene extinction that eliminated about three-quarters of plant and animal species, it seems likely that humans will not be around long enough, as a totality, to witness the geological changes I am describing.

You may be wondering what any of this has to do with Tehachapi.  Only that what we see today is as transitory as a wisp of smoke.  The tracks were first put down about 150 years ago, not even a rounding error in geologic time.  They will likely be gone in another 150.  300 years is not a rounding error, nor 1,000.  Moral?  Enjoy this while it lasts.

What I propose here is simply to follow the tracks upgrade from just below the mouth of Tehachapi Canyon to just beyond the famous loop, stopping to admire the scenery along the way, perhaps pleasing those who have not already walked over every inch of the property.  (I realize that many have.).  The survey is idiosyncratic.  I do not have an image of every tunnel.  I have not taken a photograph every one-tenth of a mile, though in places I have come close.  These are my favorite spots in the mountains, presented as they would appear to someone walking the tracks.

Each image is numbered to match a corresponding aerial photograph.

1 -- Ilmon

This location is easily accessible from Bena Road, which follows the tracks east out of Bakersfield before turning south short of Tehachapi Canyon.  Several potential images are available along the road.  Since they all look more or less the same to me, I have included only one.  Here a Bakersfield-bound stack train will soon leave the mountains and enter the San Joaquin Valley.

This aerial image shows Bena Road curving away from the tracks at Ilmon.

This aerial image is looking west towards Bakersfield and the San Joaquin Valley.  At Ilmon, the tracks are running east beside Caliente Creek and slowly climbing toward Tehachapi Loop -- 12 miles away as the crow flies, and 2,150 feet higher.

San Joaquin Valley

One cannot understand Tehachapi Pass without understanding the San Joaquin Valley, the area of central California that lies south of the Sacramento-San Joaquin River Delta, west of the Sierra Nevadas, east of the Coast Range and north of the San Emedio and Tehachapi Mountains.  When you see the valley for the first time, you are coming off mountains, regardless of the direction you are driving, and the effect is like entering a gigantic pot.  No matter where you have been in your life, you have never seen anything this flat.  Dry lake beds are similar, but this was never a lake, though it has contained lakes in the not too distant past.  The valley is over 50 miles wide and several hundred miles long.  Geology generally repeats itself around the world and through time; thus, the peaks of both the Himalayas, the Dolomites, portions of the Rockies and the Franklin Mountains near El Paso are all composed of marine limestone which has been pushed into the sky over the centuries.  But there is nothing like the San Joaquin Valley anywhere else in the world. 

How do you build a highway or railroad on ground this flat?  If a road is to cross the tracks on a grade separation, there are no cuts and thus no excess dirt that can be used to to raise the level of the highway.  So engineers sink the road into the ground about a half mile short of the tracks and dig out enough ground for the overpass.  The same holds when a railroad crosses a highway.  In his novel The Octopus, Frank Norris described the great valley as ". . . infinite, illimitable, stretching out there under the sheen of the sunset forever and forever, flat, vast, unbroken, a huge scroll, unrolling between the horizons. . . .  on that far southern horizon only the curve of the great earth itself checked the view."

I went to college in California the late 1960's and early 1970's, and one thing I remember vividly from those days was what the locals called the "tules," stew-thick fog, so thick you could feel it on your skin, named after the bullrushes that grew like steel wool in the swamps that were drained to create the incredibly fertile farmland along the Sacramento and San Joaquin Rivers.  Draining the swamps did not relieve the fogs; some claimed it made things worse.  They formed in the winter.  If you were driving west on Interstate 80, coming down out of the Sierra foothills, you could see the fog in the distance, hanging over the valley like the lid of a pot.  When you drove into the fog, you could not see a thing.  Nothing.  Only the brave attempted to cross the flatland in such conditions, and then only at speeds of 15-20 miles per hour.  The fog could last for days.  I guess people got used to it.  I know I never did.

The towns in the valley are on the same level as the checkerboarded miles of truck crops growing where the swamps once stagnated.  Portions of Sacramento and environs, at the northern edge of the San Joaquin, look like towns in the bayous of south Louisiana or in the flood plane of the Mississippi south of St. Louis, with garages on the ground floor and stairways leading to living quarters above ground, thus to avoid flooding.

In the late Pliocene, about three million years ago, neither the Sierra Nevada nor the Coast Range could be seen from the valley.  Then the Sierra fault block began to rise like a trap door opening from the east where, along the current Nevada border, the mountains rose more or less straight up out of the ground.  To the west, toward the valley, the rise was much more gradual, like an elongated children's slide.  The Coast Range was entirely different -- a fragmentary mass that, according to plate tectonic theory, first appeared as an island moving east, colliding with the west coast of North America, pushing the coastal sediments upwards to form mountains, known in geology as the Franciscan melange.  So today, when you stand in the valley on a clear day, you can see mountains to the south, east and west.  (The mountains to the north are beyond Sacramento and too far away to be visible.)

From the perspective of a locating engineer constructing a railroad to Los Angeles, the valley presents a singular challenge.  Very few routes south out of this gigantic pot are amenable to locomotives and five thousand ton trains.

This image identifies the the only available land routes from the San Joaquin Valley to the Los Angeles Basin.

1.  The most direct route is through Tejon Pass, more or less due south of Bakersfield through Santa Clarita.  This passage is extremely rugged and was deemed unsuitable for 19th century railroad construction.  In the 20th century, Interstate 5 plowed through these mountains.

2.  The only other available route is through Tehachapi Pass, leading to the High Desert north of Los Angeles and the San Gabriel Mountains.  From the desert, one can reach the Basin through either Soledad or Cajon Pass.  Soledad Pass was the original route chosen by the Southern Pacific, but it was narrow and steep, not particularly suited for heavy freight traffic.  In the 1960's, SP built the Palmdale cut-off, which allowed trains from the San Joaquin Valley to access the Los Angeles Basin through Cajon Pass, the route that the Santa Fe had used for years.  Today (December 2019), no freight traffic at all runs through Soledad Pass, now the sole domain of a commuter railroad. 

If this aerial image does not convince you that the geography of Southern California has been and is continuing to be twisted and turned like bread dough, then nothing will.    According to current theory, for millions of years, a plate called the Farallon separated the North American from the Pacific Plate, but by the late Pliocene, this huge plate had been fully consumed, sucked down beneath the ocean floor.  At Santa Barbara, or very close, the Pacific Plate first hit the North American Plate -- about thirty million years ago.  The triple junction, with the Farallon Plate being consumed, migrated north (creating what today we call the San Andreas Fault) until about three million years ago it was just west of current San Francisco, where the Farallon Plate disappeared for good.  Today, the junction is still moving north, currently at Cape Mendicino, where the San Andreas Fault terminates.

The above image shows the result of the carnage (at least according to current theory, which will likely change before I am dead).  So you are a locating engineer for the railroad at the tail end of the 19th century.  How do you move from Bakersfield (at the southern end of the San Joaquin Valley) to Los Angeles?  A hundred years later, Interstate 5 followed the route through Tejon Pass, mountains that 19th century technology could not surmount.  The only other route lay southeast of Bakersfield, through  Tehachapi Pass, climbing the mountains in a series of horsehose curves and one amazing loop, to the high desert north of the Los Angeles Basin.  Then the railroad (the Southern Pacific) could head south through the San Gabriel Mountains (Soledad Pass) to the promised land, or (in the case of the Santa Fe) east across the Mojave Desert toward Texas, Kansas City and Chicago, as well as south through Cajon Pass on a most circuitous route to the Basin.  

2 -- A grain train headed southeast to the high desert is rolling through Tehachapi Canyon toward Caliente.  Those who have photographed this area will recognize that this shot can easily be taken from a turn-out off Caliente-Bodfish Road.  This image was taken in December, when the trees in the canyon were showing fall color.

3 -- Later that morning, two BNSF Z-trains are lined up cheek to jowl on the Caliente siding, waiting for Bakersfield-bound traffic.

4 -- Here come the UP stacks.  It is probably just my imagination, but UP, owner of the line through Tehachapi Pass, seems to give priority to its own traffic over BNSF, though the latter railroad now (December 2019) seems to run more trains across the mountains.

5 -- Here is what the scene looks like to someone standing beside the road.

6 -- Union Pacific stacks have left the canyon and entered the valley leading to Caliente, where the tracks horseshoe 180 degrees and begin the steep climb (2.5% ruling grade) to the top of the pass.

7 -- BNSF stacks 0.1 mile further up the line.

8 -- UP stacks headed to Bakersfield are rolling downgrade in dynamics, passing through the bottom of the horseshoe at Caliente.

9 -- BNSF stacks and auto racks roll downgrade through the Caliente horseshoe.

10 -- More BNSF stacks at Caliente. 

11 -- The horseshoe at Caliente.

As this image demonstrates, trains headed southeast to the high desert follow Caliente Creek to its namesake at the big horseshoe.  The grade is mild, but everything changes as the tracks turn west and begin climbing the grass covered hills, dotted here and there by coast live oaks that from the air look like raisins.  Starting with Image 11, trains really begin to struggle.

This image looks southeast from Caliente toward the mountains that trains must climb to reach first the loop, then the summit just beyond the town of Tehachapi.  The arrow points to the Cliff passing siding, about 1000 feet higher in elevation than the horseshoe and about one mile away as the crow flies.  To reach that level, the tracks turn back to the west, climbing steadily for about two miles, then turn back to the east, still tracking up the mountainside through a series of smaller horseshoe curves within a single monstrous horseshoe.  The whole affair is quite fantastic, like a model railroad layout on steroids, making one thankful that the line was constructed from 1874-1876, when construction methods by today's standards were quite primitive.  If the line were built today, it would look like an interstate highway.  There would be no loop.

The Tehachapi Mountains that the tracks climb are part of the Transverse Ranges in Southern California, so-called because they generally run in an east-west direction, as opposed to the north-south direction of the major mountains ranges in that state, such as the Sierra Nevada.  This orientation was caused by the Pacific Plate's slowly rotating counterclockwise as it collided with the North American Plate.  While one plate went down into the earth (subduction), the other plate was pushed skyward (uplift).

As a result, a portion of the Transverse Ranges form a solid stone wall at the southern end of the San Joaquin Valley and as discussed above, present few openings for traversing.  What I find most interesting is the relative lack of moisture in the Tehachapi Mountains, which leads to vast open vistas.  Until one approaches the summit, there are few trees to block the view.  Thus in the image immediately above, the tracks are visible to anyone bothering to look up.   

12 -- BNSF double-stacks are whining downgrade in dynamics, approaching the horseshoe at Caliente.  

13 -- A BNSF merchandise freight is also rolling downgrade toward the horseshoe.

14 -- A BNSF Z-train fills the horseshoe at Caliente.  Notice how much elevation has been gained in this short distance -- about 100 feet.  The train is really struggling.

15 -- UP manifest in the horseshoe.

16 -- BNSF stacks have left the horseshoe and are climbing to Tunnel 1.

17 -- A UP frac-sand train is making the turn southwest toward Tunnel 1.

18 -- The DPU on a UP stack train is rounding the curve to Tunnel 1.  Above the train in the image are the tracks 250 feet below in Tehachapi Canyon.  The distance between is about one-half mile.  At this point, the tracks above diverge from the tracks below, marking the end of what amounts to a gigantic horseshoe.

19 -- A Union Pacific merchandise freight, headed compass northeast, prepares to enter Tunnel 1.  At the top right of the image, the train is curving around from Tunnel 2.  At the top left is the rear of the train,  headed northwest and about 175 feet higher in elevation than Tunnel 1.

This view looks east back into the bowl at Caliente.

The first description that I have found of Tehachapi Pass was written in August 1853 by Lieutenant R.S. Williamson, assigned by the federal government to search for a passage, suitable for a railroad, through the mountains to southern California.  Williamson and his party, from the eastern slope of the Sierra Nevada, ascended Cache Creek and discovered the valley where the town of Tehachapi sits today.  Following is the Lieutenant's description of his subsequent descent to the floor of the San Joaquin Valley, the same route that would later be followed by the railroad:
" . . . a steep and continuous descent for eight or nine miles, when we found ourselves in a beautiful prairie, apparently completely surrounded by high mountains, and as far as the eye could tell, it was a horizontal plain.

"We came to an Indian Rancheria, where we learned there was a stream of water and good grass two or three miles further on.  We proceeded to the place, and here found an excellent camping ground.

"There was another rancheria close to the place selected for our camp, and from the Indians we learned that their name for the creek was Tah-ee-chay-pah.  It is one called Pass Creek by Colonel Fremont, and is the same one he ascended when he crossed the mountains in 1844." 

The Tehachapi Mountains contain a broad base of uplifted marine limestone, the product of an ancient sea, that to this day supports the Lehigh Southwest Cement Company in the Tehachapi Valley.  The origins of that plant stretch back to the City of the Angels, Los Angeles, and its unquenchable thirst for water.  The story forms the basic plot (with Hollywood embellishments) of the classic movie "Chinatown," but without the incest.  (If you have not seen the movie, you should.  And I won't reveal any more of the story.)

Los Angeles and surroundings have mild winters that have attracted millions to an area which receives no rainfall nine months of the year, and not much during the other three (winter).  The only way to support such hordes was to transport water from the mountains through an aqueduct, an audacious plan, the brainchild of William Mulholland, that could only have seen the light of day in a time that did not require Environmental Impact Statements.

As early as 1904, the city began purchasing property in the Owens Valley, sometimes called "Deepest Valley," nestled about 250 miles north of Los Angels between some of the tallest peaks in the Sierra Nevada to the west (over 14,000 feet) and the Inyo Mountains to the east, with several peaks over 13,000 feet.  The idea was to capture snowmelt and transport it south through the mountains (and these are some very serious mountains) to the desert of Los Angeles.  

In 1908 the citizens of Los Angeles approved a gigantic bond issue to fund the project, and a cement mill was constructed in the Tehachapi Valley to supply construction materials,  because William Mulholland rejected using cement from five existing mills in Southern California, stating that they could not supply the tufa cement required for the project.  (Tufa is relatively light compared with traditional concrete and can withstand temperatures down to at least −22°F).

So Los Angeles built the small settlement of Aqueduct City, later called Monolith, just outside of the city of Tehachapi, to house the workers assigned to the new cement mill.  Many families latter moved to Tehachapi, about four miles away, to be closer to the amenities (grocery stores, restaurants, churches) that the company town could not provide.

Production began in 1909.  In two and one-half years, the plant produced 1,200,000 barrels of cement, 900,000 of which went to the aqueduct project.  Beginning about three miles north of Black Rock Springs, the aqueduct diverted the Owens River 233 miles south to the Lower San Fernando Reservoir.  Meanwhile, a group of wealthy investors, including William Mulholland, purchased land in the San Fernando Valley, which with the opening of the aqueduct soon experienced rapid development.

In 1924, farmers in the Owens Valley attempted to destroy the aqueduct through a series of bombings.  In what became known as the "California Water Wars," Los Angeles fought back and eventually prevailed in several court decisions that confirmed one of the most reliable rules of nature:  follow the money.  By 1926, Owens Lake at the bottom of Owens Valley was completely dry.  The San Fernando Valley, on the other hand, was booming.

This map shows the original Los Angeles Aqueduct (light line) and the Second Los Angeles Aqueduct (dark line, opened in 1970 to supply even more Owens Valley water to the hordes of Los Angeles).

This map shows the proximity of the First Los Angeles Aqueduct to the Tehachapi Pass line.  It also shows the "Cement Plant" at Monolith.

20 -- A BNSF manifest approaches Tunnel 2.  This freight was moving perhaps three miles per hour when the image was taken.  Shortly thereafter, the train stalled.  Based on radio chatter, I believe that one unit was not loading.  After consultation with Fort Worth Mechanical, the crew rebooted a computer in the offending unit, which seemed to solve the problem.  Fully powered, the train inched its way up the hill and slowly gained momentum.

21 -- Another BNSF manifest approaches Tunnel 2.  

22 -- On a cloudy, foggy day in December, the sun appears just long enough to illuminate a BNSF warbonnet.

23 -- UP stacks prepare to enter Tunnel 2.

24 -- BNSF power enters Tunnel 2 beside a recent derailment.

25 -- BNSF stacks, with a rainbow consist, are entering Tunnel 2.

26 -- Tunnel 2.

27 -- A Bakersfield-bound BNSF merchandise freight is entering Tunnel 2 from the south.

During the Oligocene, 23 to 35 million years ago, the area around Tehachapi Pass was a major river corridor to the Pacific Ocean, much like the Carquinez Straits where the Sacramento River passes through the coast Range.  The river likely flowed through the Tehachapi Valley and then the Cummings Valley to the immediate west and constituted the last connection between the ocean and what today has become the Mojave Desert.

In the late Pliocene, about three million years ago, the Sierra Nevada Mountains began to rise, creating massive volcanoes.  Layer upon layer of volcanic ash repeatedly covered the river, and the lush forest surrounding it was buried under tons of detritus, eventually becoming petrified wood.  As the mountains rose higher, they created the "rain shield" that denied moisture to eastern lands, creating the Mojave as we know it today. 

Uplift caused by mountain building eventually raised the Tehachapi Valley over 3,000 feet above the San Joaquin and, along with many many years of erosion, created the pass through which the railroad runs today.

28 -- After passing through Tunnel 2, Tehachapi-bound trains head generally southwest, though the tracks are constantly curving, before entering another horseshoe curve that bends each train 180 degrees to the northeast.  Here a heavy manifest with plenty of power is entering the horseshoe.

29 -- Stacks and trailers are further into the big curve.

30 -- A Union Pacific train has just exited the horseshoe on its way to Bealville.  If you follow the tracks in the background, you can see the line curving all the way to Tunnel 2, then on the other side of the ridge, running downgrade to Tunnel 1.

31 -- Bakersfield-bound stacks approach the big curve.

32 -- A BNSF merchandise freight rounds the last curve to Bealville.  

33 -- BNSF stacks at same location.

34 -- Bealville

35 -- Bealville

This aerial images shows the tracks, and the elevation they have climbed (about 600 feet), from the mouth of Tehachapi Canyon to Bealville.

In 1857, three years after the Williamson Party navigated down the side of the mountains, the San Andreas Fault produced one of the largest recorded earthquakes in the United States, with an estimated magnitude of 7.9 on the Richter Scale, rupturing the land for 225 miles between Parkfield and Wrightwood.  Called the Fort Tejon Earthquake, after the region that suffered the most extensive damage, the approximately three minutes of slippage produced a maximum horizontal offset of over 20 feet.  Railroad tracks crossing the slippage at right angles would have moved  twenty feet apart during the chaos.

Although no railroad existed during the Fort Tejon Earthquake, things were quite different during the subsequent Tehachapi Quake.  Clocks stopped at 4:52 a.m. on Monday, July 21, 1952.  The temblor measured 7.7 on the Richter scale and centered on the White Wolf Fault southwest of Bakersfield -- the most powerful earthquake in Southern California in the 20th century and the largest in the nation since San Francisco’s in 1906.  The quake claimed 14 lives, caused at least $50 million in property damage and  devastated a section of the Tehachapi Pass line near Bear Mountain. 

This image shows a vertical fracture on the northeast side of Bear Mountain along the White Wolf Fault.  Vertical displacement was about two feet; horizontal about one and one-half.   (Photo: University of California, Seismographic Station.)

A view from the entrance of Tunnel 3, showing bent rails caused by the rupture of the White Wolf fault.  Here the horizontal displacement appears to be about six feet.  (Photo: Southern Pacific Railroad)

This image from inside Tunnel 3 shows not only the horizontal displacement of the rails but also the vertical displacement of the tunnel wall, which was lifted high enough that the rail could slide underneath without breaking.  (Photo:  Southern Pacific Railroad.)

Following is a description of the quake and resulting damage, taken from The Signalman's Journal -- November 1952, page 347:

The big "killer" quake that rocked Southern California on July 21, claiming the lives of 14 persons and partially wrecking two towns, hit a section of the Southern Pacific's San Joaquin Valley line with devastating results. Most of the damage was confined to about 4 miles of track, the railroad reported. Four tunnels located on the line which makes a spectacular climb out of the San Joaquin Valley to the summit of the big Tehachapi Mountains were severely damaged. Sections of the track were kinked and twisted, and in places buried under slides. Strangely enough, although the affected area was in CTC territory, practically no damage to signal equipment was reported, except a few overturned batteries.  [Author's comment:  After all, this is the "Signalman's Journal."] Damage most difficult to repair occurred in four tunnels with a combined length of 2565 feet, the railroad's engineers reported.  Two tunnels, 360 feet and 334 feet long, were so badly damaged they were "daylighted." Huge earth moving equipment scraped off the mountains above them, converting the tunnels to open cuts. Another 700 foot tunnel had 206 feet "daylighted." The longest tunnel, approximately 1170 feet, was severely damaged for about a third of its length. A temporary track was built around it so through train operations could be resumed. The cracked lining of four other tunnels had to be repaired in places and the twisted and kinked track relaid and stabilized, fills built up and slides bull dozed away. Approximately 1,000 men were required to handle the big repair job, either working in the immediate area or engaged in getting equipment and materials into the territory, which lay some 25 miles southeast of Bakersfield, California. Morrison-Knudsen, internationally known construction company which assisted railroad forces with the work, moved onto the project the largest concentration of huge earth-moving equipment ever assembled for an emergency reconstruction job. The Tehachapi line was opened for freight and passenger service on August 18, making use of the temporary track around the long tunnel, the interior of which will be under repairs for some time.

I believe that Tunnel 3 was partially day-lighted, while Tunnels 4 and 6 were completely day-lighted .  The shoofly tracks referred to above were built around Tunnel 5, which was ultimately repaired and reopened.

36 -- BNSF stacks are entering Tunnel 3, with Bealville in the background.

37 -- A UP manifest enters Tunnel 3.

38 -- Grinding slowly upgrade, a BNSF manifest is leaving the day-lighted remains of Tunnel 4.

39 -- BNSF stacks approaching Tunnel 5.  The shoofly at Tunnel 5 is visible as a dirt road that can be followed around the back side of the ridge.  Notice how the hillside was terraced to allow the passage of the shoofly.  The entrance to Tunnel 5 is in the upper right of the image.

40 -- Dynamic breaks whining, a Bakersfield-bound manifest rolls out of Tunnel 5 and approaches  the former entrance to Tunnel 4.

41 -- UP stacks headed for the San Joaquin Valley exit Tunnel 5.  Notice the recent dirt work to repair erosion caused by heavy winter rains.

42 -- BNSF stacks exit Tunnel 5 on the way to Tehachapi.

43 -- Rolling downgrade, BNSF stacks round Curve 40 and prepare to enter Tunnel 5.

Curve 40 is a horseshoe carved into the side of a hill, rotating Tehachapi-bound trains from northwest to southeast. Around the curve stood Tunnel 6, which suffered extensive damage in the 1952 earthquake and was subsequently day-lighted.

The White Wolf Fault, which caused the 1952 quake, is a reverse fault, the largest crossing the San Joaquin Valley.  Following is a diagram showing simplistic models of common fault types:


A normal fault occurs when motion is consistent with gravity; in other words, one side of the fault remains in place while the other side drops.  With a strike-slip fault, on the other hand, walls move sideways in relation to each other, not up or down.  In a reverse fault, one side of the fault moves up, while the other holds steady.  Reverse faults such as the White Wolf are caused when land masses are being compressed, squeezed together.  Land being pulled apart creates a normal fault, such as the Basin and Range Province east of the Sierra Nevada.  Shear or sideways stress creates a strike-slip fault.  The best example is the San Andreas, where the North American and Pacific Plates are sliding horizontally past each other.  

The White Wolf Fault begins in the southern San Joaquin Valley near the Laval Road exit on Interstate 5, close to the San Emigio Mountains of the Transverse Ranges.  The fault then runs 34 miles to the northeast, near Arvin on the south side of Bakersfield, ending at the mouth of Kern River Canyon. 

Prior to the 1952 quake, geologists did not consider the White Wolf Fault a major earthquake threat, because it was believed to be too short to generate significant crustal movement.  The Tehachapi quake, however, raised the earth four feet in some places and caused severe damage as far away as Las Vegas.  There were at least 20 aftershocks of 5th magnitude or greater,  including a 5.8 magnitude tremblor that hit nearly a month after the original carnage.

44 -- A Union Pacific manifest has made the turn from Tunnel 5 and is pulling hard in the middle of the Cliff passing siding.  I believe that day-lighted Tunnel 6 was located at the big cut about 10 cars behind the power.  This is the most isolated segment of Tehachapi Pass.  The only roads here are for railroad service, and even those end at the mouth of Tunnel 7.  In case you are wondering, the photographer is standing on one of the fire break paths carved by bulldozers to prevents sparks from passing trains igniting the grass.  The same trail can be seen above day-lighted Tunnel 6 and is passable in a properly equipped Jeep.  In the valley to the right of the rear of the train sits Caliente, about 1,000 feet below.

45 -- Pushers on the same train.  View is looking southeast toward the loop.

46 -- A BNSF manifest has climbed further up the line from day-lighted Tunnel 6.  The view is from the same fire-break "road."

47 -- More BNSF traffic is climbing upgrade, about to enter Tunnel 7.

48 -- BNSF auto-racks, bound for San Francisco Bay, are about to enter Tunnel 8.  Notice how narrow are the cuts for the single track line -- a clear indication that this route was built by hand.

49 -- A BNSF freight carrying military equipment prepares to enter Tunnel 8.  For my money, this is the most remote portion of Tehachapi Pass accessible by Jeep.

This aerial image illustrates the complete isolation of the line between Tunnels 7 and 8.  There is no railroad service road between the two.  As nearly as I can tell, the only way in is by (1) parachuting or (2) hiking through one of the tunnels and then walking the tracks.  At age 69 (as of December 2019), I am no longer willing to try either. 

Because Tehachapi Pass was and remains to this day the only route from the San Joaquin Valley (and the primary route from San Francisco Bay) to the Los Angeles Basin, the line has always been a bottleneck.  (Union Pacific's Pacific Coast Line also connects San Francisco and Los Angeles, but it is slow and torturous, not suited for significant freight traffic.)  Matters have not been helped by the extremely rugged geography.  Building a railroad through such country was like climbing to the top of a lighthouse in cowboy boots -- possible, though only if one has no other shoes available.  In the case of Tehachapi, no other shoes were available.  In the early 20th century, the Santa Fe considered building its own line to Los Angeles through Tejon Pass, thereby discharging the burden of paying the Southern Pacific to use Tehachapi, as well as having to route trains via Cajon Pass to reach the City of Angels.  The proposed Tejon line would have saved the railroad almost 200 miles, but would have included 15 tunnels, one approximately 7,300 feet and another approximately 17,600 feet.  The ruling grade would have been either 3 or 3.5 percent, depending upon how much money the railroad was willing to spend.  From a railfan's perspective, I wish the line had been constructed, but the Santa Fe did not have photographers' interests at heart and scrapped the plan.

Because of the many narrow curves and tight tunnels on the Tehachapi Pass line, the Southern Pacific did not consider double-tracking a viable option for relieving congestion.  The SP did consider constructing an entirely separate track through Tehachapi Pass to the high desert.  In 1910, the company sent a survey team to locate a second line, with a ruling grade of 1.5 percent.  The line would have departed the current route at Bena, climbing the bluffs on the north side of the canyon to Ilmon and Caliente, continuing east up Caliente Creek several miles to Devil's Canyon before horseshoeing back to Montgomery Canyon, then horseshoeing again, then turning south and crossing into the Tehachapi Creek watershed in the mountains north of Marcel.  The tracks then would have worked slowly southeastward to join the original line at the town of Tehachapi.

This image is my attempt to show the route of the proposed second line, based on the references I have found.  The primary reference is Tehachapi, John R. Signor, Golden West Books, 1983.  This is a marvelous reference which I believe is no longer in print.  Many copies are available for purchase on the internet, however.  The location of my proposed route is almost certainly filled with errors; however, it does give a general idea of the path the new route would have taken, had it been constructed.
Although the second line was not constructed, the SP took many steps to increase capacity across Tehachapi Pass.  In the late 19th century, the company lengthened all existing sidings and installed new ones at Caliente, Bealville, Rowen and Woodford.  In 1909, a siding was constructed on the loop itself, named Walong in honor of District Roadmaster W. A. Long.  In 1910, workers installed a new siding, called Allard, between Caliente and Bealville.  In 1913, a short spur at Cliff was extended into a siding.  Also, automatic block signals (in the form of semaphores) were placed into service in the early 20th century.

Most interestingly, to me at least, was the Southern Pacific's brief consideration of electrification of the Tehachapi route.  Consultants proposed a ground-level, third-rail system,  because the many tunnels in the mountains were too low to support overhead lines.  I suppose a live electrical rail at ground level was not considered a hazard because of the dearth of people in the mountains.  I doubt that any thought was given to the health of local wildlife.

The project never went anywhere.  For one thing, third-rail systems are low voltage, significantly limiting horsepower, never a plus in mountains.  In addition, there was no power plant anywhere near the tracks, and the Southern Pacific, not surprisingly, was not too keen about constructing one.  And how would Santa Fe traffic have been handled on an electric line?  No one seemed to know.    

50 -- Past Tunnel 8, the line becomes accessible once again as a wide service road runs beside the tracks, a road that I have seen local landowners use repeatedly, most of them riding three-wheel "all terrain vehicles" that look like tricycles on steroids.  Here a merchandise freight rolls downgrade toward Tunnel 8.

51 -- Barstow-bound BNSF warbonnet at Rowen.

52 -- A Union Pacific manifest, struggling into the grade, has just exited the horseshoe that surrounds the Cesar Chavez National Monument.

53 -- BNSF power runs beside California 58 on the way to the Loop.  The third track sees little use today (December 2019).

54 -- Further up the line, three AC4400CWs lead a manifest downgrade with Black Mountain in the background.  

55 -- Santa Fe at same location.

56 -- Three pushers on UP stacks climbing toward the Loop.

This aerial image covers the most territory of any in this post.  The horseshoe near #52 surrounds the Cesar Chavez Monument which, as will be discussed shortly, was involved in derailing BNSF's double-tracking plans.

And now we approach the Loop.  When this line was built (1874-76), construction methods were primitive, to put it mildly.  Heavy earth-moving equipment was not available.  Workers cut through the mountainsides using horse-drawn plows; hard granite was excavated by hand with picks and shovels.  Tunnels were blasted with gun powder. The rubble was carted away by mules who walked back and forth all day from the site of a tunnel or cut to the site of a fill.  

Tunnel excavation was unbelievably dangerous. The subsoil included much decomposed granite.  Cave-ins were common. On March 30, 1876, 12 workers were buried alive after a charge of black powder exploded prematurely. Three days later five kegs of powder exploded in another tunnel, killing nine and wounding several.   

The Tehachapi line, in short, was built by hand, and not just any hands.  From the sources I have read, it appears that most, if not all, of the laborers on that project were Chinese, like the construction crews across Donner summit.  Pay was terrible, food was worse, conditions were sub-human and casualties frequent.

The jewel of this construction was the Tehachapi Loop, to this day called an engineering marvel, celebrated by all.  William Hood, Dartmouth Class of 1867, was principal engineer, and his alma mater celebrates him with a special web page from the Thayer School of Engineering:

Dartmouth produced engineers of national importance even before the founding of the Thayer School. William Hood, for example, was the engineering genius behind California’s Tehachapi Loop, one of the seven wonders of the railroad world and a National Historic Civil Engineering Landmark.
Robert Fletcher, dean of Thayer from 1871 to 1918, described the Tehachapi Pass between San Francisco and Los Angeles as “a bewildering labyrinth of lofty peaks and ridges where the roadbed twists and squirms by every sort of horseshoe curve, S curve, and spiral.”  Hood’s loop is the crowning glory of the 28 miles of rail line that snakes through the mountain pass. The elegant .73-mile spiral alone ascends at a 2-percent grade for an elevation gain of 77 feet. A train longer than 4,000 feet—some 85 cars—passes over itself as it travels along the extraordinary layout.
Dean Fletcher surmised that Hood’s training in descriptive geometry at Dartmouth was key to his success because descriptive geometry was to the engineer what the study of literature was to the poet: It “compels the man to be exact and true.” The same can be said of the Tehachapi Pass, with its 18 tunnels, 10 bridges, and Hood’s remarkable loop.

Describing Tehachapi Pass as "between San Francisco and Los Angeles" is correct, I suppose, but misleading.  It is a little like saying that the pass is "between Seattle and San Diego."  But it is correct to say the Loop was the brainchild of William Hood.  Born in Concord, New Hampshire, February 4, 1846, the son of a journalist, Hood served in the 46th regiment of the Massachusetts volunteers during the Civil War. After the war he attended Dartmouth College, leaving upon graduation after hearing of the trans-continental railway being constructed across the Sierra Nevada. He arrived in Sacramento May 3, 1867, was immediately hired by the Central Pacific and quickly advanced up the corporate ladder.  In 1875, when the Tehachapi line was already under construction, he became chief engineer. 

Hood's task was to find a route with a shallow enough grade so that freight trains could climb about 80 feet in less than a mile.  A straight line would have been far too steep, and a horseshoe curve would not have oriented trains in the proper direction.  Hood finally designed a helix to solve the problem. The first part consisted of a tunnel 426 feet long through a ridge. On the other side of the ridge the tracks turned left, circled around a small peak shaped like a woman's breast, at a grade of 2.2 percent, then traveled along the crest of the ridge, passing over the tunnel. The total length of the loop was approximately 0.73 miles.

Here is the key fact.  The celebrated loop was required not by the ruggedness of the terrain but rather by the primitive construction methods.  The loop was constructed because there was no way to move enough earth to lessen the grade.

Compare the railroad line with California 58, which follows approximately the same route through the mountains.  There is no loop on the highway, no horseshoe curve, no tunnel.  The grades are more severe, but that is only because highway traffic can handle steeper grades.  With modern construction equipment, a railroad line could be constructed through the mountains that would look like a narrow version of the highway.  The loop, to repeat, was the only way to get trains through the route chosen by the engineer -- William Hood.  Had he chosen another route, for example the proposed second line discussed above, there would have been no loop.

Why he choose that particular route is unknown.  More interestingly, to me at least:  I wonder if the loop was necessary even on the chosen alignment.

As the tracks approach the loop, they have been following Tehachapi Creek for several miles.  At point A on the aerial image above, the line departs from the creek and begins to climb a slope that, with the help of the loop, elevates trains about 150 feet above the creek at points B and C.  Eventually, at the approach to Tehachapi Valley, tracks and creek align at the same level.  I have driven along the creek all the way from Walong into the valley and have found no ridge or other impediment impenetrable to 19th century technology.  The creek is narrow and winding.  Several additional bridges and tunnels would have been required.  The line as constructed contains no additional bridges, though several short tunnels.  Perhaps the chosen route was cheaper.  I don't know.  I'm sure that William Hood had good reasons.  I just wish I knew what they were.  

57 -- This BNSF manifest is leaving Tehachapi Creek on a curved bridge and is beginning the climb out of the creek bottom to the loop.

58 -- UP stacks have come down off the loop (see stacks above lead engine) and are making the turn to the bridge over Tehachapi Creek.

59 -- A Santa Fe manifest is rolling downgrade through Tunnel 9, which carries traffic 77 feet below the loop tracks.

60 -- Southern Pacific at same location.

61 -- BNSF at same location.

62 -- This and the next two images show an interesting three-way meet at the Loop.  In this photograph, the Ringling Bros. and Barnum & Bailey circus train is climbing the Loop.  The power is directly above Tunnel 9.

63 -- The circus train has now stopped in the Loop; its rear car is visible through the short tunnel just beyond the switch at the Walong siding.  A Union Pacific freight has come up directly behind the circus train and has stopped short of the tunnel.

64 -- A short sugar beet train has now entered the siding at Walong.  As soon as it clears the switch, both the circus train and the UP freight will continue upgrade.  Then the sugar beet train will roll once again downgrade.

65 -- BNSF stacks cross under the tracks through Tunnel 9.

66 -- An SP merchandise train is rolling downgrade through the Loop, preparing to enter Tunnel 9.  Notice that, when this image was taken (1981), there was no cross at the top of the hill.

67 -- Santa Fe trailers at same location.

68 -- A BNSF Z-train climbs the Loop.  From this location, the photographer can see the horseshoe below where the tracks cross and diverge from Tehachapi Creek.

69 -- A BNSF meet at Walong.

70 -- SP power climbing the Loop.

71 -- Santa Fe power at same location.

72 -- SP power at same location but heading in opposite direction downgrade.

73 -- Santa Fe boxcars in the Loop, rolling downgrade.

74 -- Santa Fe trailers climbing the loop.

75 -- A BNSF freight, with rainbow motive power, climbs the Loop.

76 -- UP trailers in same location but photographed from different angle.

77 -- BNSF stacks crossing over themselves.

78 -- UP stacks at same location.  The lead unit is an EMD demonstrator.

79 -- BNSF meets BNSF at Walong.

80 -- BNSF at the Loop.  The "Cross at the Loop" is visible on the hill, placed to honor two Southern Pacific employees killed in San Bernardino County in 1989.

81 -- Same location but with a wider angle lens.

82 -- SP at the Loop.

At the beginning to the 20th century, Southern Pacific did not seriously consider double-tracking the Tehachapi line.  The engineering challenges were simply too great for the available technology, though political obstacles were nill.  At the beginning of the 21st century, on the other hand, the technology was sufficient, but politicians were another matter.  In 2012, BNSF and CalTrans (the California Department of Transportation, with 18,415 employees and a $17 billion annual budget as of 2019) announced a $100 million double-track project to be paid for in part by general obligation bonds approved by the citizens of California in 2006.  CalTrans was to pay half the cost, BNSF the other.  As nearly as I can tell, Union Pacific was not involved in the project.  (That is not terribly surprising.  Every time I have visited Tehachapi in the 21st century, BNSF traffic has outnumbered UP traffic by about two-to-one.)

The project was to involve five sections:

1.  A one mile extension connecting the Walong and Marcel sidings.  The original Walong siding around the Loop was only 4800 feet long, too short for all but the smallest 21st century trains.

2.  A 0.34 mile extension at the south end of the Cliff siding.

3.  A 1.5 mile connection of the Rowen and Woodford sidings.

4.  A 2.75 mile connection of the Caliente and Bealville sidings.

5.  A 2.69 mile connection from Bena to Ilmon.

The entire project was estimated to take eight years and be completed by 2020.

A year later, however, BNSF announced that the project was being seriously curtailed.  Only the first two items would be constructed, at a cost of about $35 million.  The project was truncated because of concerns voiced by the National Park Service that part of the work (the connection of the Rowen and Woodford sidings) would harm the Cesar Chavez National Monument.  According to articles in the Tehachapi and Bakersfield newspapers, a Park Service official sent a letter to CalTrans, raising concerns that the rail project's environmental review understated impacts to the Chavez property, which had been declared a national monument by President Obama.  Specifically, the Park Service was concerned about "dust and noise."

I have seen the Cesar Chavez National Monument.  As nearly as I can tell, the only things there are a sign, an old tuberculosis sanatorium which, on the day I visited, was completely deserted, and the railroad tracks that surround the area on a large horseshoes curve.  Mind you, the tracks have been there about 150 years and for the most part can't be seen except along the driveway.  On the day I visited, no one was there except me, no one to be bothered by "dust and noise."  The place was completely deserted.  Also, I did not see any dust or hear any noise while I was there, even though three trains came through.  Well, I guess the trains grinding upgrade made quite a racket, but they will make the same racket on one track or two.  Thus was the plug pulled on years of planning.

The delay caused by the Park Service's complaint caused CalTrans to scale back its share of the project, because money from the general obligation bond was running out.  So BNSF scaled back its portion, as well.  Construction on the section from Walong to Marcel began in May 2015 and concluded in October 2016.  Engineers had to work around  Tunnel 10.  Instead of trying to widen it, they left it intact and carved a huge cut for the second track.  Today Tunnel 10 beside the new cut looks like Bear the Mighty Dog (my buddy who weighs ten pounds) next to a Great Dane that might fall on him at any moment.  (The slight lengthening of the Cliff passing siding was also completed at that time.)  

83 -- A BNSF manifest grinds upgrade through Tunnel 10.  The new completed second track is visible in the huge cut.  The contrast gives some idea of the difference between 19th and 21st century railroad construction.  The cut is what the Tehachapi line would look like were it built today.

84 -- A BNSF grainer on the new track.

85 -- Stacks on the new track.

86 -- Stacks on the old track.

87 -- Manifests meet on the lengthened passing siding between Walong and Marcel.  I believe that this location is known as Burton's Corner, named after the railfan who bought property at the curve to enjoy the passing trains.

88 -- Full view of the curve at Burton's Corner.

And so we come to the end of our brief survey.  I have followed the line from Photograph 88 to Tehachapi, but nothing in that section does much for me.  I know others feel differently, and that's fine.  Some people like beets; I don't.  I like a good rib-eye; others don't.  The world is large enough for us all.  I only wish that Southern Pacific had built that second track up the Tehachapi Mountains to the town with the same name.  Wouldn't that have been something?  It would have made my day.

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