Northwestern Pacific Railroad Network

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I tried doing a forum search for "automatic block signals" and didn't find anything so I was wondering if this subject has even come up before.

Did the Southern Pacific ever install any automatic block signals on its Northwestern Pacific subsidiary?

I have seen typical SP style "searchlight" or "target" signals that protected drawbridges but what about longer stretches of road?

One time I thought I saw some block signals at either end of a long siding somewhere on the southern end of the line north of Novato.  It was a stretch that ran along side U.S. 101 for a short distance.  The signals I remember seeing didn't look exactly like the SP target signals in use throughout the so-called "Golden Empire".  Unfortunately, I cannot remember exactly what they looked like.

Does anybody remember seeing this?


Fred M. Cain

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I did a little bit of digging (recalling seeing something about this earlier) - the location you reference north of Novato is known as 'Burdell'. I've seen the siding used to store empty/loaded grain hoppers in the last couple years, though there's no reason it couldn't be used for passing.

There's a great photo essay that fellow member Dave S. shared on this site back in late 2013:

Also an excellent resource is this thread over at Trainorders:,3428790

Finally, here's a Google maps aerial view:


You know, that is probably the signals that I saw there.  As I said, they looked different that the other classic SP style "searchlight" signals.  Traveling at 60 MPH on U.S. 101 it was hard for me to get a real good look at them.

So, I think we can conclude that there were no automatic block signals on the NWP (unless, of course there were some back in the electric days but that was way, way before my time).

Here is a thought:  I recall reading somewhere years ago that the SP had THREE daily road freights a day in each direction during the postwar traffic peak.  That's a lot of traffic to have squeezed through the Eel River Canyon.  Throw in the daily passenger train (Budd RDC) and the dispatcher(s) must have had their hands full keeping that line fluid.  Just a thought.


Fred M. Cain

Fred:  I would also like a definitive account of signal systems on the NWP, so if you find that let me know. But we can assume that the NWP was mostly dark territory.

The interurban system definitely had them:  various generations of banjo, semaphore, and color light.  But old NWP photos do reveal some signals elsewhere, for example south of Tunnel 4 (facing both directions).  I've seen evidence in Ignacio, but maybe in connection with a station that was once there.  As you note, all the movable spans had them.  (My photo is of the distant signal to the Brazos bridge, east approach.)  I read recently that Tunnel 27 (Island Mountain) had them.

In its heyday, the NWP had something like 15 train order offices to control traffic on the line.  I would imagine an ABS system through the Canyon would have added substantially to the maintenance nightmare, and many false red signals, so hardcopy train orders might have been a more practical solution.

I've been meaning to spend some time at the NWPRRHS archives to do some research on this topic, but am incredibly busy between work and home projects.  Someday!  [I only have time on this site today because I'm waiting for a dental appointment.]

If you have any additional questions about Burdell, I would be happy to make something up (as I have better than total recall).


Hmmmn.  You've got me to wondering.  There may have been some signals, I don't know.  I have this vague memory - ant it's really vague so maybe I shouldn't even mention it - but I thought I saw what looked like the remains of a typical SP style automatic block system code line around the siding at Island Mountain.  Does anybody know that?

After all, the SP did run daily passenger service from Willits to Eureka.  I remember seeing that in the SPTCo public timetables in the 1960s.  I used to wonder why they would run that Willits-Eureka and not from Oakland.  How many passengers could such a limited market attract?  What was the justification for the Willits-Eureka RDC in the '60s?  But now I'm getting off the topic of signals.

The other puzzle, why did the lineside open-wire lines have two crossarms as seen in early, pre-1965 photos?  Was the bottom arm for signal wires or for something else?

Here is a nice picture (if the URL doesn't break) of a typical SPTCo style signal line shot in Oregon.  The open-wire signal line can be see to the right of the picture. It is typical of the kind of lines I remember seeing in the Southwest as a kid.!jig[1]/ ;


Fred M. Cain

I would imagine that the number of crossarms on those wayside poles is proportional to the number of telephone circuits, and perhaps some additional circuits for local signalling purposes.  In San Rafael I think today there still stands one or two poles that used to carry signalling for the many at grade crossings there.

Don't know if NWP wayside poles carried telegraphic signals as I don't recall any station photos which showed a telegraph rig, but phones were a plenty.

However, the recent book "Lifeline of the Redwood Empire Boom and Bust 1951-2001" mentions that Pacific Telephone owned and maintained the wayside poles in the Canyon, and had a speeder shed with two speeders for its maintenance people.  A very unique arrangement, I think.  (Need to go re-read that part tonight!)

In any event, in the Canyon it is likely that those wayside poles carried NWP phone lines and non-NWP phone lines, perhaps residential phone lines?

After the NWP equipped engines and cabooses with radios those lines probably were made redundant.  In later years SP installed microwave relay stations to support radio communications in the canyon.  [Eventually SP's extensive system-wide interstate microwave and then fiber optic network was spun off as SPRINT communications.  Remember them?]

As I remember the siding at Burdell was where the scale was located. The signals in question indicated if speed across scale was correct. they were white in color and would either flash or stay on steady to indicate speed.

At Burdell there were actually two types of signals:

1)  Red/Green dwarf signals at the spring switches at each end of the very long siding to protect facing point moves over the spring switches.

2)  Pole mounted white signals which (as Alex mentions) supposedly helped the engineer manage his speed as he approached the Weigh-In-Motion scale.  These were not searchlight type signals.  These were actually grade crossing warning light housings with a clear (instead of red) lens.


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