Saturday, September 13, 2014

PHOTOS: Port Road Trips - CRESS to HARBOR

It's no secret that the PRR was never a huge fan of CTC thanks to their abundance of multi-track main lines and manned interlocking towers.  So far we have seen an example of the PRR's use of CTC without traffic control, ie remote control interlockings, but a predominance of Rule 251 operation.  However due to its rather constrained geography that favored single track lines with passing sidings, the Susquehanna River valley also featured two genuine Rule 261 signaled CTC lines.  One of these is the Buffalo Line running north of Harrisburg and, of course, the other is the Port Road Branch running from PORT to PERRY.  So while the remaining segments of our Port Road Trip may seem a bit less interesting than those that came before, it actually represents an opportunity to examine a method of operation common to the rest of the rail system that the PRR tended to avoid.

So passing CRESS we finally leave the COLA CTC zone...or at least the Harrisburg Division CTC zone.  Below CRESS the Port Road entered the Maryland Division and if you recall the COLA interlocking sheet there are 50 levers on the 150 lever CTC machine used by the Maryland Division. These 50 levers control the 9 interlockings south of CRESS and north of QUARRY.  Today we will be looking at the intermediate signal south of CRESS, the HARBOR siding and a little bit of the Safe Harbor substation complex.


Between CP-CRESS and CP-WEST HARBOR are the MP 35 automatic signals C357 and C356.  Remember the mileage is now counting down towards Perryville instead of Parkesburg.   Here we see the two signals looking westward with the Fisherman's Run flume (aka shoefly) far in the background.  At this point the A&S is running parallel to the Port Road about 20 or 30 feet up the rocky slope.  The signals are arranged in the typical fashion for a single pole catenary structure with one PL being mounted on the catenary mast and the other on its own mast.


The C357 signal is displaying an Approach indication for the  stop signal at CP-CRESS.  Although CRESS features a medium speed turnout, because it is the entrance to double track ABS territory there is only a straight and a restricted speed route available and therefore C357 does not need to display Approach Medium.


Here in this rather backlit reverse view  we see the C356 mast signal.  The layout of this intermediate is a bit counter intuitive because the signal that is unable to display Approach Medium is the distant for an interlocking with only restricted speed routes while the signal that can't display Approach Medium faces an interlocking that could have a Medium speed route if not for the Rule 251. Note the lack of pole line power tap.  Here the 6000 volt, 100hz power supply was running up on the A&S alignment and feeding both it and the Port Road.


The reason for the lower head | on C356 is not because the Harbor siding was ever downgraded in the Conrail era, but instead because of the short (5000 foot) distance between  CP-HARBOR and CP-WEST HARBOR.  Trains diverging at CP-WEST HARBOR would get an Approach.  Trains stopping at CP-HARBOR (perhaps for a meet) would get an Approach Medium.


This rather long shot of C357 shows the signal displaying Approach in the time before the dispatcher lined a route at CP-CRESS for an eastbound NS freight train.  Around 2010 all the catenary poles were chopped down by NS.



After the re-signaling project a new bi-directional mast was installed with Darth Vader signals.  The odd layout has been replaced by Approach Medium signals in both directions.  Not sure I agree with the placement of the signal and the relay box on the lake side of the tracks.  This part of the river is a well known flood risk.


CP-WEST HARBOR, at MP 33.2, is the west end of a 5000 foot long restricted speed ending.  It was located in the shadow of the impressive Safe Harbor viaduct and adjacent to the Safe Harbor Dam.  The single \ on the lower head is all you get in this situation.  If the siding were signaled this signal would also come with a lower head \ for Slow Approach.



If you review the COLA interlocking charts you might notice that the all the Harrisburg Division interlockings use lever numbers ranging from 6 all the way up to 120.  With only 150 places where is there room for the Maryland Division levers?  well the 1997 Conrail interlocking charts shed some light on this mystery.  The switches and signals clearly have numbers ranging from 5 to 54, which match what is listed on the COLA chart.  The charts show that some sort of re-labeling is in progress, but those suffixed with L or R also have labels starting with 2 (254L, switch 205, etc).  This would have been a simple way to separate the different areas of responsibility in the tower and also prevent number overlap. 

Not seeing any better alternative I will simply call this the 254L signal at CP-WEST HARBOR.


Here in the 2011 view you can see that the signal had indeed been painted sometime prior to the 2004 photo above.


Still in 2011 we see the original PRR style concrete relay hut in front of the viaduct supports.

When SHOCKS through CP-CRES was  being resignaled in the 2007 time frame, CP-WEST HARBOR was actually given a minor refresh with satellite communications replacing the original pole mounted code line and a few other updates such as new point machines.  The line was originally control by the US&S 504B code system, which was also in service in the ALTO tower zone of control until until that tower closed.  I suspect that the satellite simply tunnels the 504B codes as that would be far simpler than trying to re-work an elderly relay interlocking plant.


Back to 2004 we are looking at the westbound 254R signals in front of the CP-WEST HARBOR relay hut.  As expected the signal off the siding in a dwarf and the main track has a gantry mounted position light.  I believe that by this point NS had already applied the aforementioned "minor updates" which also included the removal of the Stop and Proceed marker from the westbound high signal.


Safe Harbor was also the location of one of three section substations on the Port Road Branch.  We'll talk about that more later, but the westbound signal gantry also supported the catenary feeds from he substation.  Here is the non-repainted 254RA signal.  The proximity of the 12kv feeders must have made signal maintenance a real headache.


Here is the 254RB dwarf signal for trains heading off the jointed rail siding.  As this is used for more than "wrong direction" operations the signal id equipped to display Slow Clear and Slow Approach.


By 2013 however the partly modernized CP-WEST HARBOR had been replaced in a project to upgrade the Harbor siding to the signaled variety with Medium speed turnouts.  Here is the replacement relay hut in front of the Safe Harbor dam.


Consistent with NS's style the  westbound signal gantry was replaced with a cantilever mast seen here from Amtrak's 2013 fall foliage train.


In an even more bizarre scenario  NS was unhappy with their original re-signaling and is re-rebuilding CP-WEST HARBOR about 500-1000 feet to the west to increase the capacity of the siding.  This new attempt comes complete with three head signals capable of displaying Medium Approach Medium and rule 280a "C" signals in case they ever do go the 562 route.  This is the new interlocking location as seen in fall 2013.


The Safe Harbor dam is special because it not only generated 60hz three phase power for the grid, but also has two dedicated turbines generating 25Hz single phase power for Amtrak.  With a maximum 25Hz capacity of 81MW this power is sent to a large step-up substation where it is then fed into circuits running south to Perryville, East to Parkesburg and West to Harrisburg/Enola.  Here we see the step-up substation with the 12kv Safe Harbor section substation in the foreground.  Note all the old circuit breakers and switchgear are still in place.


The row of large step-up transformers converting 12kv power from the dam to 138kv transmission voltage.


This building is the Safe Harbor substation equipment room and also contained one of two 100hz signal power plants that was used by Conrail after the end of electrified operations in 1980. 


 Two of the three feeds were active until sometime after 2007 when NS converted the line to use local utility power.  One feed went north towards Enola, the other south towards Perryville.


 Here we see the 6000V power lines reaching up to the Port Road.  By this point in 2011 the lines were out of service, but the catenary poles had yet to be removed.


Another view of the Port Road signal power feed.  This pole also supported the signal power transformer for CP-WEST HARBOR.


In another non-standard PRR action, only one siding end point was given a "direction" name, which differs from most other railroads which tended to use two.  So CP-WEST HARBOR, MP 31.9, is matched by CP-HARBOR, not CP-EAST HARBOR.  HARBOR is pretty much a mirror of its western counterpart, just not overshadowed by the hulking A&S Branch right of way.  Here is a backlit 2004 shot of the budget style catenary gantry mounted main signal for eastbound trains. 


A closeup of the 250LA signal reveals the existence of a Stop and Proceed marker as well as a 'SP' plate indicating that the signal is connected to a Slide Protection device.  The 'SP' plate was another PRR innovation that instructed any train passing an 'SP' marked signal at Stop and Proceed or Restricting to be on the lookout for fallen rocks.  I am unsure if NS ever upgraded CP-HARBOR to remove the marker light has had been done at CP-WEST HARBOR and others.


Eastbound 250LB dwarf signal hanging out in the weeds that give a clue to how often the harbor siding is used.


This wide view of the 250R mast  gives several other clues that this interlocking had yet to see any modernization.  First, paint on the PL mast is not as fresh as was seen at West harbor and appears to be from the Conrail area.  Second the Restricting \ is not fitted with a backing plate and third the signal is still the old style "single control" M-3 type that was originally fitted to the line by the PRR.  Note that the CP-HARBOR relay hut is of a semi-corrugated metal type construction instead of concrete.


The ever cost conscious PRR  was very stingy when it came to the use of anti-glare backings on its amber PL signals.  The thought was that trains would be traveling slow enough on Approach by the time they reached the signal that there was no need for "fast" recognition of the signal aspect.


Well that's it for this segment of Port Road Trips.  Tune in next time as we travel on to CP-MIDWAY and the Holtwood Dam.

2 comments:

  1. Great set of photos as usual. Where are you getting the 66MW (assume you meant MW, not MHz) capacity figure for the dam? Wikipedia's article says 81MW, consisting of 56MW from two 25Hz turbines and 25MW from a motor-generator. That figure is backed up by the dam's own website (http://www.shwpc.com/facts_figures.html) if one assumes an 80% worst-case power factor.

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    1. I was looking at the Wikipedia article on the dam itself. Guess they weren't in sync.

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