SP Jawbone Branch (Part 59) - Thoughts on Operations at Owenyo, Some Planned Changes Oct 2025

While my last post was more on the various bits of research I picked up at the CSRM Library, in this post I want to start going into the reasoning of some of the things I have found and what effects those will have on the layout's design.

Why Go West? A Continued Discussion on the Center Siding vs. Main Track

SP 2576 with Mixed No 788 arriving at Owenyo circa 1940 - Phil Serpico - owensvalleyhistory,com southern_pacific015_sml

The prototype Owenyo operations appear to have used the far track from the transfer platforms as the Main Track and also the track which took the arriving train into.  Some evidence suggests that the ~20 car lengths between the main switches to the wye was used to hold the consists while the engine ran around the wye to get on the South (RR West) end of the cars.  Most consists would have fit within the straight side of the wye to allow this.  The siding and house track were about 43 cars long, which was plenty long to accept any train size. 

Track Plan Changes & Discussion

While I found enough evidence of the west track being used as the main track several years ago, I am starting to consider another possibility for the operations of the trains upon arrival at Owenyo.  One of my main thoughts is to increase the size of the wye at Owenyo with a larger radius curve to allow more accurate and proportional modeling of the company housing inside of the wye.
I still would like to know why the SP decided to shift the main track from the obvious center alignment to the west track.  Anyone that actually knows 110 years ago is long gone, so I'll have to use other reasoning to sort out why that might be.  Now that I'm considering changing the wye radius, a new possibility came into my mind.  What if they wanted to arrive on the west track, so that the engine could use the wye to make the run around and get on the south end of the train to work it from that end of town?  The 

Over-layed Track plan from 20250926.  Currently the (right) 26"Radius wye, and planned (left) with 46"R curve with more buildings inside the wye.

Operationally, I could also consider that the arriving train would clear the south switch of the wye, and try to fit a consist within the wye's straight leg.  Roughing out the wye radius at around 46", will result in a tangent length of about 10-11 cars.  Ideally my consists into Owenyo will be in the range of 12-15 cars to be prototypical.  I figured out, if I need to, the arriving engine could double a couple of cars off the head-end of the train into the wye with the engine.  Then the cars could either be dropped in the wye tail, or if the train is blocked well with either the MW water cars or the GS gondolas going to the south end's dump trestle immediately after the engine was turned in the wye.  Then the cars of the inbound train could be switched from the south end and swapped with cars that were ready for pickup.

I would imagine that the caboose would be set over into the south curved wye leg, next to the water tank to pull out the inbound cars to be switched.  Photos taken either during the layover or during switching show the caboose left on the 'main' right north of the road crossing, which would make it a short walk over the NG tracks on the road to the Depot, but I've not seen any with the caboose spotted on the 'water' leg of the wye. 

Owenyo with Mixed Train coach & RPO/Baggage on main track looking north, circa 1930-40s - owensvalleyhistory,com - ebay35_owenyo_sml - (Lightened)

 Back in the mixed train era, it seems that the RPO/Baggage and Coach were turned fairly quickly and then spotted on the west track (Main) just inside the wye's straight leg, opposite the depot and just north of the road crossing.  In the photo above the engine is back over at the oil tanks simmering away, and some of the cars have been spotted in the center track also.  

Possibly the cars spotted in the center track are cars that have been loaded already, but it's hard to tell in this photo how far through the process of working the various cars in town they are.  Obviously there's still loading of Dolomite from the side-boarded flatcars into the boxcars at the platform north of the road crossing.  Back in this era the SP operated the mixed train nightly, six days a week, probably with two sets of engines and passenger cars.  They only overlapped at Mojave by about 90 minutes in the middle of the night, so any delay in switching would have resulted in the eastward train being delayed.  The crews seemed to have the most time to rest at Owenyo in that era, with the 16-hour law in effect.  While it might have been possible for the crew to run Owenyo to Mojave, turn in 90 minutes, and return to Owenyo in 16 hours, it would have been very tight if any switching or delays en route happened, so I am currently believing that they had two crews working two trainsets per day and that would also line up with the hinted at rumors that the train was 'always late' coming in, probably because they're stopping to do work at the other industries along the line as needed.

SP 102856 post-war B-50-series boxcar SPNG Owenyo Transfer Dock 1954 (Cropped to XM & Caboose) - owensvalleyhistory,com s-l1600_ebay01_sml 

Likewise on the railroad, nothing ever changes... the Mixed's RPO/Baggage and Coach gave way to cabooses during the war.  So my guess there is that the caboose would only have been spotted over to the south wye curve, next to the water tank, for a few moments while the inbound cars were pulled out to be worked from the south end of town, and then the caboose would be set back to the main so as not to be beat up during the switching. 

Looking North from the Transfer-Dump Trestle, "1930s" (but the bulk-loading conveyor was built ~1940) - Andrew Brandon collection (cropped)

With the caboose respotted on the main track, as seen in the two photos above, the crew could work the inbound cars and cars spotted along the house track, shuffling them between the 3 available tracks from the south end, see photo below.

The Trainmen's company building was located out in the middle of the wye, on the centerline of the wye tail track, and away from any other company houses.  A couple of trees grew on the west side of that company house (bunk house?)... which I'm guessing would have provided some shade in the later afternoon before the sun went down.  I believe there was also one smaller tree on the south side of that building, which probably helped a little with the shade.

The location of this "Trainmen" house is rather interesting, as it's well away from the SG engine "spot" next to the fuel tank, and also quite a ways from the "spot" where both the mixed train left it's RPO/Baggage and the Coach, along with the later Caboose "on-spot" next to the depot and the road.  Perhaps this house was for the NG's crew... but that seems a bit weird as it's completely on the other side of the SG from the NG equipment.

I'll have to re-read some of the books on the NG about how the "Hotel" was used, I seem to remember some of the single men living there, but I don't recall if that's where some of the train crews stayed.  The SG crew may have also lived out in their Caboose... with the engine crew staying in the Hotel or in other accommodations.

The rebuilding of the train seems to have been fairly simple, sort out all the cars from the various spots, put in the empties to load, and shove all the 'pulls' back against the caboose. 

Thoughts on the Transfer Trestle

I believe the 'full spots' of the dump trestle were probably done with a 'handle' of the cars either going in or coming out, so that the engine didn't have to reach in under the tell-tails located 60ft away from the end of the trestle.  The swapping of the loads and empties was probably done on the main track, then the empties were on the north end and shoved under the trestle to load and uncoupled.  Followed by the loads pulled out and shoved down against the caboose on the main in the yard.

Owenyo Trestle - SG side - unknown calander photo - Ronald Grau collection-A

Another thought I've had with the transfer trestle has been, if the NG cars were working multiple different materials, wouldn't the SP standard gauge cars have also been required to be swapped out to match?  Maybe the reason for the extra cars being spotted at the trestle was the "other commodities" GS gondolas that were't fully loaded yet, which would have to be swapped out to finish loading after another trip on the NG to the get right ore/minerals?

SP North End Owenyo with GS-Gondolas in north tail track - Ronald Grau collection

I'm not sure why there's four SP GS gondolas at the north end of town here, unless they've been shoved out of the way up here for some other reason. 

SP 3203 Owenyo - Eddie Sims Collection February,1951 Ronald Grau photo

But whatever this reason was might also explain the photo of SP 3203 working the steel rebuild-sided UP GS gondola at the north end of town, although this might just be the SP 3203 running around the consist or shuffling a few things from the north end... but it does show that they were still using the north end around 1950-54.

Owenyo seems to have regularly needed 2-3 GS gondolas and 5-8 boxcars for the transfer platforms, etc.  The occasional stock car outside of the Livestock Specials, and the regular rotation of SPMW Water Canteen cars to various outlaying company section gangs seem to have happened too once the SP expanded the water facilities at Owenyo with the larger 20k gallon tank sometime between 1950 and 1953.

I suspect some of the GS gondola loadings may have been more complicated, possibly with a "which day is the NG getting what mineral?" arrangement.  I'm guessing if that was the case, then the SG would have had to spot the correct set of gondolas to get only that mineral/ore and then respot it for the next day to get the other type of ore/minerals.  Also the reality of 6-9 NG A-frame gondolas unloaded brings up the question of really how many Standard Gauge 

Owenyo Wye Run-around & Bartlett?

In my operations any cars going to be back-hauled to Bartlett and Little Lake will have to be reblocked into the departing train before leaving Owenyo, as only Little Lake will have a siding allowing easy run-arounds on the return trip.  Bartlett is a trailing point switch on the return trip to Mojave, although in some eras it did have a small run-around within the plant.  I'm not sure how much the SP actually spotted the plant at Bartlett vs allowing the in-plant cable car-mover or hand-mover to be used to reposition the cars.  The two tracks of the run-around may have functioned as an "empties in, loads out" arrangement, so the SP engine didn't have to go down in right against the plant.  Some of my production data shows that the plant may have required 6-10 cars per trip, possibly seasonally... so I'm guessing that they may have done a spot on the way north to Owenyo and then again on the way south to Mojave, although car loadings like that would have taken up most of the car capacity on the branch, so I'm still unclear on how much traffic would go certain places.

To Prototype or Not to Prototype?  Considerations on the arrangement at Bartlett. 

Currently, I'm also making a consideration on if I want to flip the Southern Columbia Plate Glass Co. buildings and spurs to the far side of the main track, which would put the building against the backdrop showing mostly dry Owens Lake.  If I try to put the plant along the aisle, I am not sure it will work out well, with 40ft tall plant buildings much of the length along the aisle, with the cars hidden behind that, and the whole plant would also mask much of the view of the backdrop.

If I am able to flip the plant to behind the trackage, then the whole plant should be easier to switch and view.  A standing consist may be blocking the view of the spotted cars and plant, but the crew could just as easily 'skeet' the cars not being worked could be kept along the doorway, and clear of blocking the view of the plant.

MW Cars on the Center Track?

Owenyo with SPMW outfit cars on the SG's center track, SPNG 9 in foreground - May 30, 1956 - Evan Werkema photo - TrainOrders.com (cropped to show Outfit)

A very nice photo of SPNG 9 and SPNG 1, but over the top of them are three very nice SPMW standard gauge cars spotted on the center track with their access ladders in place on the east side of the cars. Looks like a good use for my SPMW Pullman car and what looks like a B-50-6/9 converted to a bunk car, plus some form of B-50-8/10/11/13/14 (can't tell exactly the class) probably material/tool car for the outfit.  Notice the bright aluminum paint on the roof of the retired Pullman car, which doesn't have any A/C ducts.

Bealville Spur Outfit with deployed SP Standard stairs. - My photo, June 8, 2018 (Color Adjusted)

Some photos (such as the one above) suggest that MW outfit cars were actually stored on the center siding track, with ladder/steps set up onto them, so they weren't going to be moved anytime soon. 

SP Owenyo North End and Wye with "Halloween" RSD-5 1958-1960 - Andrew Brandon collection

This would suggest that the engine would use the wye as the escape track after arriving.  Another shot of an RSD-5 around 1957-58 at the oil tanks suggests from the dirt in the railheads of the center and house track, that only the Main track and the wye was being used, as there was dirt/minerals sitting on the rail heads of both the siding and house track at the North (RR East) end of the wye.

In Closing

My closing thoughts on this post are mostly that this is a continuing discussion in my own mind and now on these blog pages of what I'm planning to do.  There will be more posts, probably focusing on the topics covered here in the near future.  I'm hoping to get some new materials purchased for the rebuilding of the Owenyo modules to match the new design.

Jason Hill

Related Articles:

Jawbone Branch Layout Build Index - Overview of all my SP Jawbone Branch articles so far.

SP Jawbone Branch (Part 58) - CSRM Visit & Notes From New SP Drawings

The middle of August, I was able to go visit the Library at CSRM, specifically to look at Jawbone related drawings and photos.  

New Researching Tid-bits!

Sample of the CSRM Owenyo Station Map 1"=100ft scale drawing I found!

This drawing is one of the standard "Station Maps" in the "ValMap" style, which has historically been exceptionally useful for researching and building models of the shown infrastructure of the areas shown.

Specifically one of the best drawings I found was '-Station Plan of- OWENYO (Owenyo Branch) Inyo Co. California, Scale 1"=100' dated 11-15-1948.  Revised 11-06-1950, 6-15-1951, and 2-5-1954.  A couple of notes on the drawing are noted from a set of "Proposed Sanitary Facilities from Aug 24, 1957 as well.

CAD model in progress for Owenyo in "full" HO-scale based on new research!

Among the useful tid-bits I found so far in this drawing include:

1. Water Tower is shown as 20,000 Gal. Wat.Tk. 14.75ft x 16.0ft Diameter Tank (on Timber Tower 17.0ft high) G.M.O. 43651 11-10-1950
I guess I need to go back through my drawings from Part 57, when I made the mock-up for the water tower.  Now I can revise it and get it much more accurate... and also judge how close my estimations were.

2. I found that there was an storage shed and an ice house in the nook between the road and western (southern) curve of the wye, away from the main track next to the water tower and pump house.

3. Most of the Company Houses inside the wye are shown as constructed from car-bodies, nominally 34ft long and 27ft wide.  I'll have to play around with the "building blocks" of the car bodies to see how those would be worked into a gabled house design.  The drawing shows several of these houses with add-on sheds and lean-to's, and also fence lines.

Of the seven company houses inside the wye, they were as follow north to south.  Four Company Houses, followed by the Carman's House, then the Lineman's House, and then the Agent's House.  

The loose building centered out in the middle of the wye is shown for Trainmen... I'm not sure if that was the Trainmen's washrooms or if that was a bunk-house for the train crews.

4. I found out there was a small Post Office opposite the T-intersection of the road next to the water tank.

5. Oddly the Cistern that I found in the field a couple years ago is right in the middle of the street.

6. There are WAY more out-buildings than I figured before from the aerial photos.  Now it's pretty clear the dimensions of these structures, so there's way more info that I dreamed of getting.  What's interesting is that the company housing carbodies were on SP property, but the outbuildings, such as garages, sheds, etc were on the other side of the property lines, sitting on City of Los Angeles land.

7. Steam Lines were still in place from the Oil Pump House to the elevated eastern wye leg (north end of town).  The lines had three steam columns to work the transloading to the NG tank cars in the pit.  The SG track is listed as elevated by 4ft and the NG track is depressed by 4ft.

8. The transfer deck platforms between the SG and NG tracks are specified more accurately, so I'll need to go through them and check if they'll still fit on the layout.

A Disturbing Revelation

Sadly, I'm now starting to reconsider my choice of compressing the wye to use 26" Radius curves.  The main issue is how I really can't have the company housing inside the wye.  If I resize the wye, nearly doubling the size to something on the order of 44 to 48" Radius, it will still be nearly 1/2 the full sized one, but it would put the west switch (south end) of the wye correctly aligned with the road and platforms.

Looks like my layout needs "wye enlargement therapy." 

Oddly, I'm actually mostly ok with this idea.  I've already torn up the switch that would need to move to relay it in Code 70.  It would require me completely rebuilding the Wye Tail module.  The equilateral wye switch on the west tail was a little tight, this would allow me to use a more standard No.7 Frog switch.  I could also extend the tail of the wye long enough to turn an engine and two 60ft passenger cars on the wye, which would be nice for operations.  Also I'm considering selective compression to the buildings in and around the wye to keep them from being 'too large' for larger, but still compressed size of the wye.

I'm also considering alternate track arrangements for Bartlett, which will make the layout more fun and visually appealing to look at.

Other Drawings

Several other drawings I found were for various proposed Engine House arrangements for Owenyo.  One was one that was going to be placed over near the old NG turntable and car shop facilities.  The other concept was to place a SG Engine House inside the SG wye.  While I don't plan to build any of these alternate designs into my model of Oweyno, but it is very interesting to consider what the SP Operation and Engineering Departments were thinking to write up a blog post about these drawings.

What About Bartlett?

In other digging, I was able to find a 1927 drawing from the Clark Chemical Company at Bartlett.  If I recall, this was one of the test plants that was built to pilot the development of the product from the Owens Lake.  However, given the history of this plant and the shape of their spurs, I won't be modeling this complex.

The size of the plant was much bigger than the Southern Columbia Plate Glass Company complex, which lasted into the 1950s, and was rebuilt into the plant that exists in it's abandoned form today.

No Little Lake?

Little Lake Depot Station 1940 ucla_little lake08_sml - Owens Valley History,com

Unfortunately, I wasn't able to find anything really useful for the SP facilities at Little Lake, outside of the photos I've seen before of the Little Lake station.  I think I came across another copy of the same station picture as was posted on the OwensValleyHistory.com website from the UCLA collection

.

Jawbone Branch Engineering Vellum

I did find a large pack of vellum engineering data pack for the "Lone Pine Branch", which included the line all the way to Owenyo.  

This is the title block from the vellum engineering pack for the "Lone Pine Branch" from 1953. CSRM colleciton

This set of drawings shows the grade profile of the route, including the natural lay of the land and the roadbed grade.  The top-view shows data for the X-Y curve and tangent data.  Bridges and culverts are listed on this map.  It's nice to see a complete set of this sort of information.

Bridges?

Owens River Bridge - lone_pine_09_sml - Owensvalleyhistory,com

I also found a set of drawings for the Owens River Bridge, including the Concrete Abutments and spans, including several photos.  There was also a set of drawings for the Ballast Deck Bridge over Cottonwood Creek, near Bartlett.  It might be fun to build a model of one of these smaller ballast deck bridges.

Cover of the Owens River Bridge Engineering data package - CSRM collection

The Owenyo Station plan shows that the Ballast Deck Culvert next to the large dump-trestle shows as only 6ft long and about 2ft tall, but the width shows as about 16ft.  I'll look forward to working this into the Owenyo #3 Module.

I'm planning to do a post or two on these big bridges of the Jawbone Branch.

In Closing

All of this new information has been marinating in my mind for the last two months.  I've been working on getting the permissions from CSRM to actually share some of the research on my blogs discussing them.

Updated Jawbone track plan concepts from 20251004 with flipped Bartlett trackage and 46"R wye.

This is my current scheme for the layout's plans.  I'll be covering these concepts and changes in more depth with upcoming blog posts.

Jason Hill

Related Articles:

Jawbone Branch Index Page of Layout Articles

SP Jawbone Branch (Part 57) - Rough Owenyo Water Tank Mock-up - before I got the new info.

SP Jawbone Branch (Part 57) - Rough Owenyo Water Tank Mock-up

Back in late 2023 I was working on making a set of CAD models for some of the Owenyo buildings that I'll be needing for the Jawbone Branch layout.

Water Tank - Owenyo station with tank and 5501 RSD-5 - Andrew Brandon collection - Cropped

A month or so ago I picked up some foam-core from the new Hobby Lobby in the local city.  They're offering fairly large sheets for $2.00, which I couldn't hold out on getting several sheets any longer.  So for under $7, I bought three sheets with the plan to start making some mock-ups of various Jawbone Branch structures that I've been planning for several years.

Owenyo Water Tank Foundations, Oct 30, 2023, my photo.

So after the SPH&TS Convention in Bakersfield, I went to do a field trip to Owenyo on the way home.  During this visit, I brought a notebook and took measurements of the remains at the site, including the cast concrete water tank foundation blocks.  So at least I know that the footprint of the water tower is 100% accurate and correct in size.  The height of the tank I've had to work at a bit more, but given the plethora of photos, I think I have it pretty close to the correct size.  I could probably stand to down-size the water tank by 10%, but for now I'll see how it looks at full size.

Footing for Owenyo Water Tank paper print.

Recently, I formatted these drawings to make scale elevation and foot-print to be printed on standard 8.5 x 11 sheets of paper.

Elmer's brand craft spray adhesive.

The printed elevation drawings are then cut out.  Spray-glue is then used to attach the trimmed paper elevation prints to the foam-core material.

Side and front view of legs with diagonal braces, plus hexagonal tank platform attached to Foam-core sheet.

Once the paper prints are glued to the foam-core, I cut them out with a No.11 Exacto knife and a razor-saw.  It took a little practice to ensure the No.11 cuts were square to the foam.

I also put the foundation and tank-top on 0.02-0.03" thick styrene sheets.

I also made the rough core of the water take from a supplement pill bottle, which was slightly undersized for the water tank diameter. I cut several sections of the side elevation of the water tank, which will give me the height.  The pill bottle is some form of PVC-type plastic, which was a little hard to cut with the razor saw, but once I got a slice through the shell, it went very quickly.  I cleaned up the cut edge with the No.11 blade.

Mock-up In 3-D

Completed 'rough' mock-up of the water tank.

I then sprayed the bottle with the adhesive and stuck the printed paper wrapper to it.  The bottom of the bottle will be the top of the tank.  After the spray was applied, I placed the paper wrapper into the glue with the original bottom of the bottle on a piece of Masonite flat surface, so that the wrapper was even with the bottom of the bottle.

Some of the underlying color did 'bleed' through the think paper wrapper.

Track-end view of the water tank in place in relation to the curved wye track.

The think plastic roof panel was roughly cut into a circle and placed on the original bottom of the pill bottle.

A reverse angle looking back towards the Owenyo yard.  I didn't happen to have an SPMW CS-25A water car handy.

The prototype tank is very interesting in that the tank's platform was built out of a set of hexagonal head timbers, then a bed of stringers placed on top of that, which I haven't modeled on this rough version.

A high-angle view of the water tank with the Owenyo yard.

In the right foreground, I'll need to make a mock-up of the water pump house.  There was also a fairly large tree, which will occupy most of the rest of the space between the oiled-dirt road and the dirt road that crosses the curved wye track.

I'll probably do a little coloring on the major parts of this model once the glue dries.  At least painting the tank a medium-dark gray/black.

Enlarged & cropped photo of SP Company House inside Owenyo wye - 1960, Alden Armstrong photo.

The left foreground of the high-angle shot shows the corners of the footprints penciled in for a couple of company houses, so I'll be getting to make those mock-ups for those at some point.  While the real Owenyo had about 5 company houses inside the wye, I'll only have room for about two.

In Closing

This project was a fun learning project to refine my building  'mock-up' skills with the foam-core.

SP Company Village Owenyo with coaches looking north circa 1940 - owensvalleyhistory,com - ebay35_owenyo_sml - (Lightened - Cropped)

I'd like to continue making a few more of these 'cheap' mock-up buildings and get a chance to evaluate their size and placement on my model of Owenyo.  While, I want to have the SP company village, it will be a bit challenging to have it along the front edge of the layout and not getting bumped too much during operations on the layout.  Thankfully, most of the heavy "operations" will be down at the west end of the town (to the right) away from most of the foreground structures.

Jason Hill

Related Articles:

SP Jawbone Branch (Part 39) - A Ferro-Equestrian Archaeology Field Trip - Research Trip Nov 1, 2023.