SP Jawbone Branch (Part 44) - Owenyo Transfer & Commodities

I covered the basics of Soap Stone in Owens Valley Mining (Part 1), but I think the topic of Owens Valley Mining is specialized enough that the detailed dives into it should split a bit from my regular Jawbone Branch series of blog posts.

SP 3203 & SPNG 9 both working around Owenyo in Feb, 1951 - Martin Hansen collection

As I want to get more into the research of the Owens Valley Mining and what was shipped by rail.  To do this I'll be borrowing the table from Joe Dale Morris' excellent book SP Slim Princess in the Sunset 1940-1960, plus I'll be adding in the research I'm doing for the Jawbone's standard gauge line down the west side of Owens Lake and south through the greater valley towards Inyokern.

SPNG Shipments

SP 102856 boxcar at Spot 11, according to my spot numbering system, on SPNG Owenyo North Transfer Platform (NTP) in 1954 - owensvalleyhistory,com s-l1600_ebay01_sml

Many of the transfers at Owenyo won't be too obvious what exactly was being moved between the NG cars and loading the SG cars.  I hope to have some fun with staging figures with all the sacks, bulk, bagged, piled timber, wheelbarrowed, hand-trucked, or conveyored lading being moved.  The NG also received outside freight forwarder shipments coming in from the rest of the world to the folks on the SPNG villages and mining camps.

List of industries & commodities shipped on the SPNG - table from Joe Dale Morris's SP Slim Princess in the Sunset 1940-1960 book.

Some of the shipments obviously dropped off by the 1940s that I'm modeling, such as the silver ore and bullion shipments, while others, such as the Perlite, didn't come until a couple years after my modeling era cutoff.  Sadly most of the colorful operation of bulk oil movements by rail to Owenyo proper and transfer to the SPNG was abandoned after WWII, as the traffic using the newly upgraded US Hwy 395/6 allowed semi-trucks to haul the fuel in from Mojave and Route 66.

I'm still looking for more information about exactly how much production was shipped by each of the various industries.

Modeling Owenyo Operations

Early development car-spot numbering for my HO-scale Jawbone Branch.

By 1952 the SP was using a station number system.  Owenyo was assigned 3144, Bartlett was 3130 and Little Lake was 3089.  Mojave was 1579.  I'm not sure exactly what the numbering was based on.  It doesn't appear to be the same as the Santa Fe's system which was by straight Mile Post number.  The SP system seems semi mileage based, but with different number series, changing by division.

I will be using the station number system with additional digit at Owenyo to show spot number based on the chart I made above, which is my own fabrication.  Two small changes to the drawing need to be made.  Because the Dump Trestle is going to be shortened to only 4 cars, Spot 5 is now assigned to the Stock Transfer Platform.  The second is that the lower through track in the chart is actually the mainline, so spots 26-30 are not correct to be shown as a place to leave cars, so those spot numbers should be considered void.

Loading chart 2024-04-26, roughed in for total car capacity calculations.

The above loading chart for traffic on the Jawbone Branch is currently just a rough form for me to work out the average train size and how much traffic that will represent on the layout as a baseline.  It seems I could add a bit of traffic or adjust the car counts at Little Lake to have a bit more traffic on Day 1 and Day 5.  Probably in the form of a few extra mineral cars to Owenyo or non-peak season stock car movements.  In reality, these light spots were probably filled by traffic for Lone Pine, but as I won't be modeling Lone Pine (at least currently), I won't have to deal with that traffic. 

I'll be planning to mix up the assignment of cars at Owenyo.  The Transfer Trestle (OTT) probably was spotted and allowed the smaller NG cars to be shoved up and dumped into the standard gauge cars over a couple of days to reach full loads.  There may have also been some separation of either which exact car was shipping bulk soapstone, vs dolomite, vs talc.  It could have also been some days they had one commodity and the next trip it was something else. 

Edit 2024-04-29: There's some new info coming together for Bartlett that indicates the production was at least partly seasonal.  I'm not sure what the production fluctuation, if any, would equate to in terms of carloads being shipped and fuel being supplied by tank cars.  I'll probably adjust the number of cars in and out of the Bartlett plant, but I'll talk about this more in a future post.

More Research to Do

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

Perhaps that's what I'm seeing in the above photo and some aerial photos where an extra set of GS gondolas were off-spotted on the trestle lead track.  The Joe Dale Morris book includes some description of the NG's operations regarding which days of the week where the NG went and collected cars from.  This could give me more info as to which days of the week the transloading was done to the SG cars.  Still more research to do!

In Closing

Hopefully the research on the mining will make my operations on the model more realistic than just shuffling plastic boxes around.

I'm going to wrap up this first of the Owens Valley Mining series at this point.  I'm already starting Part 2 and Part 3 so I don't make each sub-topic too long of a post.

Jason Hill

Related Posts:

Owens Valley Mining (Part 1) - Soapstone - An Unexpectedly Useful Material - Really the first in depth post about mined minerals from the Owens Valley, so I could say this was really part 1 of this series.

Jawbone Branch Layout Build Index - Construction of the layout postings.