How to get accurate track grades and hights for IRL routes?

Hello, I've been working on my Lehigh Valley route again however I've been having issues. I'm up at Lehigh Gap (For reference it's where the Lehigh and New England crossed over the Lehigh valley and CNJ mainlines via a massive s shaped bridge. The bridge is gone in present day after being torn down round 1967.) I can't find any track charts on the area and am having a hard time figuring out what the gradients and how high off the ground the bridge was. If anyone has ideas on how I can do this please let me know as it would be greatly helpful. Thank you to anyone who reads this and have a good day

Have you tried contacting the respective historical societies? These groups offer a lot of information on stuff such as this and I'm sure they would be more than willing to help especially if you showed them parts of your ongoing project. A fellow Trainzer and I worked on a B&M Hoosac Tunnel route, really it was the other Trainzer's route but I helped with stuff. We contacted the B&MHS and they really got into it. Their then VP helped us with details and even gave us copies of his book he wrote on the Hoosac Tunnel. Their enthusiasm was truly an impetus for Mike to go at his route with furvor.

Is this the bridge?
I don't find gradients and such but here is some good info from 1912 "Engineering Record" - a free PDF on Google Books
https://play.google.com/books/reader?id=pSwxAQAAMAAJ&hl=en&pg=GBS.PA8

According to WIKI, "... torn down in 1967, but its foundations on each side of the river are still visible as are telegraph poles." That should give a good indication of the alignment. Do any of the area hiking trails follow the original track bed? Barring any other better information, taken together, these should give a good guess as to the original grade.

One of the problems in recreating historic lines is the lack of contemporary data. Those that used it knew what and where things were. I doubt they ever thought someone in the future would want to model it. So I feel that a best logical guess is all that often can be done. If anyone challenges that, let them produce the contrary evidence.

I didn't try yet but you can probably still see parts of the foundations that were left in place in Google Earth. Maybe even cuts and fills on the approaches.

1611mac's link above is to a 1912 book with 3 page article about the Lehigh Gap Bridge - actually the building of the L&NE Tamaqua Extension and the bridge. The height of the subgrade across the bridge is shown as 485 ft and the Lehigh River water level as 374.5 ft in the diagram in the article.

If you're having trouble accessing the link you can PM thru the forum message system.

Bob Pearson

For a close approximate height, although, it is fairly accurate, use the Google Earth application (not maps.google.com) to get the elevation. You can hover your mouse cursor over a point and get the elevation of that location, which is located along the status bar on the lower right corner.

Forgot to mention the article referenced above includes a track profile for the extension between Danielsville and Tamaqua. Gives track height vs miles along the track with grades indicated. You can get decent pics from the pdf downloaded and that would give a general idea of the grade. Limiting factor would be getting the distance in miles from some reference point.

On a slightly different note. TransDem is made for doing just this type of thing. Download a DEM of the area and you have heights at any point. Download the historical topomaps - 1950 is readily available for this part of PA as geopdf. Display the topo on the DEM in TD and you can use the tools in TD to draw the route following the track shown on the topo. Doesn't have to be too accurate you just use it to filter the baseboards and utm tiles that TransDem can make automatically from the topomap. Can't be easier. Don't I wish. But everyone needs some help doing it the 1st at least.

Gook luck,
Bob

Any bridges like this in trainz?

I'm currently working on my route of the Lehigh gap however I've run into an issue on what I can choose for a bridge. I haven't found anything on the DLS when searching for a truss bridge that looks like the one I'm trying to find. Idk if anyone knows of one or can aid me in the search but If so thanks. Bridge hunter says its a Baltimore deck truss but searching that brings back nothing. If anyone does trainz model commissions please tell me. I'll be more than willing to pay for a model of this bridge. Thanks for reading all

ReadingRailroadFan20 said:

I'm currently working on my route of the Lehigh gap however I've run into an issue on what I can choose for a bridge. I haven't found anything on the DLS when searching for a truss bridge that looks like the one I'm trying to find. Idk if anyone knows of one or can aid me in the search but If so thanks. Bridge hunter says its a Baltimore deck truss but searching that brings back nothing. If anyone does trainz model commissions please tell me. I'll be more than willing to pay for a model of this bridge. Thanks for reading all

Click to expand...

Look at Ben Dorsey's bridges. You might find something like that.

The alternative is AustinHockey316 (I think that's his username). Look for RRTK bridges. There are various ones that you can cobble together - you'll need to connect a piece of bridge track in between the parts, but you might be able to get the components.