This might be a stupid question, but when power lines follow along a track, what happens to the line when the track goes into a mountain tunnel? Do they run the line up the mountain and down the other side to meet up with the track? do they run the line into the ground ajacent to the track and go through the tunnel? or do the lines continue into the tunnel on poles? I never thought about it before, until I purchased some poles for my layout and have to figure out where to put them? What have you all done?
Thanks
Chris
To the best of my knowledge, most power lines that followed the tracks were strung over the mountain, rather than through the tunnel, safety being the key factor.
Telegraph and telephone lines were sometimes run through the tunnels.
In well-developed areas, both power and phone lines were often run under overpasses with the tracks.
This is another one of those questions that are difficult to answer authoritatively. Practices varied from region to region. If your poles are carrying telegraph or phone lines, running into the tunnel may be appropriate.
Hope this helps a bit.
Darrell, quiet…for now
Railroad telegraph and telephone lines were always routed over the mountain, rather than through the tunnel, so that they would remain operational if the tunnel wasn’t (for anything from an in-tunnel derailment to a complete collapse.) During those pre-radio times, those were the only line of communication with the dispatcher and the operators on the other side of the mountain.
On the New York Central route along the Hudson River across from Bear Mountain, several sharp ridges of rock came down to the river. The rails tunnelled through, but the pole line went around on the railroad grade, along a shelf just about wide enough for a pickup truck.
Chuck
The lines along the track followed the lay of the land. If the track went through a tunnel, they went over the mountain. If the track went into a cut, they stayed on the top of the rise. If the track went on a fill, they went down into the valley.
Your post does not mention or ask about putting in actual lines between poles. I have heard many people don’t because of all kinds of problems(This list too long to mention here). If putting in real lines has entered your thoughts, check out EZLine from http://www.berkshirejunction.com/ This stuff is great. Once up, you can hit it, drop stuff on it and it bounces back into shape. If the poles are glued in, they will never know they have been tugged on. Highly recommended!
As an engineer for a local power company, I’ll agree that railroads almost always routed their power lines over or around mountains and not through tunnels. Since the railroads were not in the business of selling electricity, it was for their own use such as signaling, they were always looking for the least expensive method of construction and maintenance. Lines strung on poles are usually un-insulated conductors since they are inexpensive, lighter than insulated cables, and have a greater current carrying capacity than insulated cables. Insulated cables are considerably more expensive.
To run power lines through a tunnel would most certainly need insulated cables or the tunnel bore would need to be significantly larger to provide proper clearances around the conductors. The type of construction used in a tunnel is often known as “mine” or “lashed” cable. It uses a support wire called a messenger which is made of galvanized steel, or copper or aluminum clad steel to hold the current carrying conductors. The current carrying conductors are lashed to the messenger with a small gauge wire continuously wound around the cable bundle, or are held to the messenger with a series of steel bands.
Also, in the event of a cable failure or break, it is much quicker and easier to splice un-insulated cable than insulated cables. A failure in a tunnel cable could easily shutdown rail traffic through that tunnel for several hours while repairs were made. Not a situation that the railroads would like to face.
Here in the Eastern US, electric utilities often ran pole lines adjacent to railroad right-of-ways. If you’re ever casing a long abandon “ghost” rail line, one way to find the old ROW is to look for power lines that don’t follow the modern roadway. The pole line will often take a straighter route than the roadway and may cross the road back and forth as the elevation changes. The pole lines are usually still in use even though the rails have long since been removed, and the utility cer