old RR bridge over I-390 by Rochester airport

Looking at the various features on the 1935 map, it seems that the colors might indicate property ownership and/or easements. RR's were very heavily taxed for their real estate and individual track mileage, so I imagine that was carefully mapped. For example, look at the PRR vs B&O color arrangement on both sides of the crossing.

If i am right we can't infer much about the actual bridge dimensions, girders, etc from the 1935 map. Note how the 4 B&O tracks are tightly together in the middle of the B&O coloring - maybe the bridge was much narrower than the map coloring.
I'm not convinced there were 2 bridges at all. Perhaps today we still have the 1935 bridge.
JS
If I'm right about the colors, still puzzling would be the "tower" on the 1935 map, located over Chili Ave, which would be outside of a narrow bridge. Could be some other explanation there....

The map is wrong. No tower in the sense of tower controlling tracks. I stand by it unless you have photo proof. Maps are very frequently wrong. I agree with a shanty or something.

It's not on any of the valuation maps I have nor any ETTs.

sd80mac wrote:

nydepot wrote:Tower? No tower.

sd80mac wrote:And the tower is on Chili Ave???

Please see the photo..

After looking at the map and zoomed in more than last time, I missed the bridge symbol. So the tower was ON the bridge... That's unusual placement for building to go on bridge. (if there was actual tower)

So no tower at all? Map's wrong?

OK guys, I *THINK* I can clarify the issue a bit. Maybe not to everyone's satisfaction but hopefully it will make some sense.

As I see it, we have three phases of track layout represented in the pics and maps.

1. The "old" or "original" layout, as shown in CPS's post of a 1920 map on page 1. (Sure wish this site numbered each post!).

2. Go to the 1935 map Kevin posted. The location of the crossing has been changed to the bridge - compare with the 1920 and it's obvious. But zoom in and pretend you are a PRR train. The PRR trains northbound for example had to go onto the B&O Eastbound Main itself, then cross from the Eastbound, onto the Westbound, and then the Thoroughfare, by means of crossovers. This would likely require the use of an operator and/or a switchtender to line the route (6 switches just for a PRR northbound to get through). So the tower shown on the 1935 map - be it an actual "tower" or a 1-story shanty we don't know - was for facilitation of movements through this mess of trackage.

3. Now CPS posted a pic from June of 1941. There is trackwork going on and it's obvious they are installing diamonds for the PRR to cross directly. I'd bet at the same time they also simplified those other tracks as well. So probably at this time, with the installation of the tilt board, possibly a telephone booth, and other applicable rules, the use of humans on site in the tower was no longer needed.

My speculation is that the tower, in whatever physical form, was a temporary measure lasting from the building of the new bridge prior to 1935, until the diamonds were installed in 1941.

#2. I think you are looking at it wrong. The PRR line clearly heads straight across everything (despite the improper joining of the images for the map). The track just to the left is the B&O barge canal sidings.

The B&O track chart from 1930 shows the PRR heading straight across. PRR maps also show it heading straight across. The tower is not on the 1930 track chart. But given the crossover and yard tracks starting up between the Barge Canal and Chili Ave, maybe the tower was for all of that?

The PRR maps show a tilt-board from the line relocation opening up.

You may well be right on #2. I guess I was seeing what I thought I was seeing on the map but it COULD be the PRR going straight across. And looking at the pic in post #8, there's a 5-man crew doing work but a close look does not show any actual construction - they could be tightening bolts or tamping up a low joint.

OK, I'll withdraw my speculation, and we're back to not knowing what and what-for the "tower" was! Whichever of you guys it was building that time machine, step it up a bit, would you?

Could the "tower" be a reference to the tilt-board support structure? It could be a kind of tower, much like today's "radio towers" or "cell towers".

Here's the tilt-board signal in 1978:

https://www.flickr.com/photos/85501582@N03/32608130770" onclick="window.open(this.href);return false;

-otto-

Otto, that's probably EX-1, coming "around the horn" from Exchange Street. IIRC at that time that was the route not only for traffic on the former PRR, but also for the EL and LV lines south to Lima and Avon. A convoluted route for sure.

Looks like the tower is in the wrong place to be the map depiction.

RailKevin wrote:Looks like the tower is in the wrong place to be the map depiction.

Agreed. The tower on the map was not a long-term proposition, and I'd say chances of actually seeing a picture of it are very slim. The thought even occurred to me that one of those shantys - if it actually was the "tower" - could have been moved from one location to another as needs changed. A Brownhoist or other derrick could have moved it from one side to the other, or any scenario you'd like. Or maybe the structure in the pic has nothing to do with the tower.

FWIW, I believe that there still is a truss bridge from this line that crosses the canal, and today carries a pipeline spur to the tanks located across the canal. I've crossed it once, hoping that there might be a path on the other side, but alas, there really isn't, because it's very overgrown.