by Patrick Harris
“Why do they call it that?”
A friend of mine asked me the difference between a “mainline and a short line”. I could see the confusion, and sought to clarify, so I sat down and jotted some observations from years of railfanning. The crux of the point is that terms for describing “who” a railroad is sometimes sound like a description of what its various parts are.
A “short line” is a way one might classify or describe an entire railroad, while a “mainline” is a section of track that is part of a railroad’s network. Major intercity/cross-country routes are referred to as “mainlines” because, as the name would suggest, traffic levels make them the main lines used.
Class one roads are the biggest lines as determined by various standards, but essentially BNSF, UP, CSX, NS, KCS/TFM domestically, and CN/IC/WC, CP and BC Rail in Canada are the last North American class ones. These have “secondaries” or “subs/subdivisions” that have substantial traffic, but less than main lines. Class Ones (though this could also apply to a “regional”) also have “branches/branchlines” that are more lightly used, usually less well maintained and serve a few industries and communities. These are lines that are often on a “hit list” to be abandoned these days due to lack of adequate revenue generation or difficulty in maintenance that outweighs revenue offsets. Railroads are sometimes disallowed to abandon by the (now) Surface Transportation Board or by a court. Municipalities, businesses or states may oppose abandonment or desire to purchase right of ways the railroads wish to cast off.
Railroads of all sizes also have “spurs”, usually a short section of track that connects to an industrial complex or larger businesses. They also have “passing sidings”, which may be used to allow one train to move off the main (or “through”) track so that another may pass, and regular “sidings” which are used to park cars at an industry immediately alongside the track or simply as a parking lot to set a car off because it needs to be put out of the train for a variety of reasons.
A railroad with lesser revenue and trackage is often referred to as a “regional”, so termed because they usual serve a particular geographic region or revenue source. Examples: Wisconsin Central, Lehigh Valley. Though they both achieved Class One status due to high revenues, both served limited geographic areas. This shows how the terms can blur, because if a road achieves high enough revenue, it can transcend into a “major” line, but still be limited geographically and be considered a regional. Toe-may-toe, Toe-mah-toe. Shortlines are often industrial lines or branches that were cast off/abandoned by regionals or Class One lines. The old logging and mining roads would be examples as well, but modern short lines are just as likely to either be owned by the city/county/state it serves, or part of a corporation that owns multiple short lines, like the Genessee and Wyoming, RailLink, or RailAmerica, which each own many short lines.
A bridge line is a railroad that (usually exclusively) transfers traffic from one railroad to another, usually as a shortcut or between two lines that do not meet or cross. This is often referred to as “overhead” traffic, indicating it originates and terminates off-line from the bridge route. The Lehigh and Hudson River was one such line. It bypassed the northeastern urban centers, allowing fast freight to go from Pennsylvania to southern New England without having to pass through Philly, NY or Boston. The curse of being a bridge line is that usually the line itself does not generate enough traffic to keep the road open, so it is somewhat at the mercy of the “feeder” lines that give it cars to transport. It is especially rough when the same road is at each end of that line, at which time there was little incentive to give the bridge route any cars to handle—time meant less than miles traveled for the car. If it took three extra days to move a oxcar exclusively on home rails and deny a competitor haulage, it would take the most roundabout route that would allow it to remain on “home rails”. This sort of thinking put customer service last and was not good for the economy.
Railroads are paid by the percentage of the distance hauled (this is a VERY rough approximation of how cars are billed, but sufficient for this point). If the Penn Gulf hauls a car only 10% of its routing, it likely is going to lose money on moving it and will avoid taking the car at all. A way around this would be to charge an outrageous car handling fee to discourage the shipper from using the railroad at all for transport and thus avoiding the money losing move.
For example: Penn Gulf hauls a car 600 miles, and the Southern hauls it 400. Switching and car handling fees aside, the roads would split the fee 60/40. Both routes will probably make money on it, so it is interchanged. Now, let’s say that Santa Fe brought it from LA to Chicago, 60% of the way. Penn Central movies it 25% of the way, from Chicago to Easton Pennsylvania, Lehigh and Hudson River moves it 10% of the way to southern New England, and Providence and Worcester the last 5%. If the Lehigh doesn’t charge a car handling/switching fee, they may well lose money on it, and the P&W almost surely will unless they get a per diem or car handling fee.
One southern example of a bridge line was the Columbus and Greenville, routed between the eponymous cities in Mississippi. When the GM&O and the Illinois Central merged, there was no more need for C&G to carry cars east and west across the state between the two north-south lines. C&G petitioned the ICC to be taken over by the new Illinois Central Gulf because the merger eliminated their traffic nearly entirely. After only a year or two, the C&G petitioned to be made independent again because their on-line customers were being ignored by ICG, the physical plant was eroding due to lack of ICG maintenance, and ICG was considering abandoning it altogether. ICG dumped many lines that have later been run profitably by others, showing the short-sighted nature of ICG and, later, IC management. The C&G is now a profitable independent short line, but no longer relies on bridge traffic for its livelihood.
Bridge lines, along with routes that paralleled each other, were some of the roads to be swallowed in mergers. Another ICG castoff, the MidSouth, was originally an IC line running from Birmingham to Tuscaloosa to Meridian to Jackson to Vicksburg and on to Shreveport. When the IC was turning itself into a “north-south only” line, it sold off that line, which became the MidSouth–a very long bridge route with only modest online traffic. Other than the little C&G’s Mississippi-only haul, it was the only east-west route from mid-Alabama all the way to Shreveport. It had not been well-maintained by the ICG, but MidSouth scratched out a living as a bridge route carrying overhead traffic from points east of and around Birmingham and Atlanta to the hub of Shreveport. Western goods flowed in from points west to Dallas and were funneled through Shreveport and Jackson to the Heart of Dixie. KCS saw the potential in the route, bought the MidSouth, and changed it from a 15 mph bridge line to a 60mph raceway between Dixie and the plains of Texas.
Bridge lines have, over the last 30-40 years, often been successfully integrated into larger routes to smooth the flow of traffic. KCS went from a north-south road to one of the best-connected mid-south and southwest lines due to the acquisition. Bridge lines don’t have much of a place in a world with only 4 major east-west lines (CSX, NS, UP and BNSF), but one of the few places they still have value is as routes around major gateway cities and their choked yards. The major east-west gateways are: Chicago, St. Louis, Kansas City, Memphis, and (to a lesser extent) New Orleans. Lines such as the Toledo, Peoria and Western (TP&W) have offered a way to bypass the choke points like Chicago, using slogans like “Faster through Peoria” (used by the Peoria and Eastern, a New York Central subsidiary) and “The Peoria Gateway”.
TP&W was the object of a ferocious court battle (all the way to the big boys, THE supreme court) between the Santa Fe and the Pennsylvania, each trying to control it. Santa Fe ended up with it, giving it haulage from California past Chicago all the way into Pennsylvania (remember, longer hauls mean $$$). ATSF could not seem to make a go of it, and the TP&Wbecame independent again, though not until ATSF had taken all their newer locos and left them with ATSF GP20 junkers. The TP&W did well for a number of years, and then came under the control of the New York, Susquehanna and Western (NYS&W), AKA the Susie Q — and as of a couple of years ago, RailAmerica. Who knows what tomorrow holds for the TP&W? Like all bridge lines, it is inherently risky to operate, but has its advantages and allure. The book “How Railroads Work and What They Do” is an excellent primer on the entire subject, and is a “must-own” and “must-read” for any serious railfan.