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Stand on a bridge in the Chicago suburbs of Highlands or Hinsdale that spans the three-track BNSF main line headed west out of Chicago to Aurora, Ill., during the evening rush hour, and you may see half a dozen or more sets of headlights approaching.
What you are witnessing is the nightly parade of outbound Metra commuter trains on this mostly straight, and therefore fast, stretch of track, nicknamed the racetrack. On an outside track, locals are making every station stop, while on the center track express trains bypass some of the stations. The third track sees a less intense pace of Metra trains headed in the opposite direction, including some that have reached their end-point and are now headed back inbound.
But, though this is very much a commuter train show, often you will find a freight train (and even an Amtrak long-distance train) added to the mix. This is, after all, one of the most important freight routes in and out of the U.S. freight railroading capital, Chicago.
Yes, BNSF, which inherited the line from predecessor Burlington Northern, does try to schedule its freights around the morning and evening commuter rush hours. But, in freight railroading, everything isn't always predictable, and a "hot" intermodal train has to get to its destination on time, too.
COEXISTENCE
The BNSF racetrack, which has had commuter traffic essentially going back to its beginnings, is one of the best examples of how intense commuter rail traffic can coexist with freight traffic. And it's a good example because it has almost all of the physical characteristics of the line in its favor.
Looking at the well-choreographed ballet that interweaves trains on this line, you would think that adding commuter rail to an existing freight line should be simple. But you would probably be wrong.
Any Amtrak manager at any level will tell you, it's almost impossible to maintain a tightly scheduled passenger operation on a single-track freight railroad main line with widely spaced sidings. There are just too many things that can go wrong — and too few options available to the dispatchers who manage traffic on the line. And, on many Amtrak routes, you're only talking about one or two passenger trains a day in each direction. To offer commuter service on a rail corridor, you need a number of closely spaced trains during both the morning and evening rush hours — and, if possible, additional service throughout the day.
BNSF's dispatchers on the racetrack have three tracks to work with, accompanied by frequent cross-overs that allow trains to move from one track to another at fairly fast speeds.
LOOKING TO EUROPE
Rail transit and passenger train advocates often cite European rail systems as an example of how freight trains and passenger trains can coexist — and how railroads can offer fast and efficient transportation services.
One reason European railroads manage to mix passenger (both long-distance and commuter) traffic with freight trains so well is that almost all major main lines are double track, with routes that have substantial commuter traffic often being four main tracks. The latter is extremely rare in North America. Additionally, European freight trains are usually much shorter than those found in the United States, while often having locomotives with the equivalent horsepower assigned to much longer and heavier American trains. That factor lets the European freights move faster — including having quicker acceleration when they do have to stop — and therefore fit in better with faster-moving passenger trains.
And, electric locomotives pull most of Europe's rail traffic — passenger and freight — on electrified routes. (Switzerland, with abundant hydroelectric power, is the world leader in railroad electrification, with more than 90 percent of its railroad route miles electrified.) Electric locomotives (and electric self-propelled railcars) have a substantial acceleration advantage over diesel power.
CONVERGENCE
In the past few years, interest in American passenger rail, including commuter rail, has intensified due to the convergence of a range of factors. Growing cities have found their road systems increasingly clogged. Even Interstate highways in urban areas often become parking lots when traffic exceeds capacity and a single minor accident causes mile-long backups.
Both the ever-increasing cost of oil and environmental concerns, including both pollution and greenhouse gases, have contributed to the re-examination of rail as a more efficient and cleaner means of moving people.
And passenger trains are suddenly fashionable. Just look at the number of television commercials, selling products or services unrelated to train travel, that either use modern trains as their settings or show them in the background. Even automobile ads now include high-speed train images.
Last year, several heavyweight studies and conferences have looked at America's railroad map and seen the possibilities for additional long-distance passenger routes and additional commuter services in urban areas.
To which, the major railroads, both individually and collectively, have said, "Not so fast."
THE RAILROAD PERSPECTIVE
"Piggy-backing on privately owned and operated freight railroad assets will give America a third-rate passenger system," Edward R. Hamberger, president and CEO of the Association of American Railroads (AAR), the trade group for large railroads, said in response to one of these reports.
"Successful passenger rail systems — like those in Europe and Japan — rely on publicly funded track and [that is] almost exclusively dedicated to passenger rail," the AAR president said.
To understand the AAR's position, you have to look at how America's railroads have fared in recent years.
Freight railroads saw a major upsurge in traffic toward the end of the 20th century — and suddenly found themselves short of the infrastructure they needed to handle that traffic. While railroads continue to handle a wide range of goods, two types of traffic particularly contributed to increased demands: America's increasing demand for foreign-made goods, transported in long strings of intermodal container trains, and the need for more energy, handled in long unit coal trains going to power plants.
Additional factors include the recent boom in ethanol production, which, due to its chemical characteristics, is not suited for movement in pipelines, and therefore needs to be moved in railroad tank cars or tanker trucks, with railcars being the more efficient means for hauling large quantities.
For much of the early part of the 20th century, America's railroads were either in decline or struggling to survive in a regulatory climate that made it difficult to adjust to changing economic conditions. Up through the 1970s and 1980s, major railroads abandoned or sold off lines. To economize on track maintenance costs (and property taxes), some multi-track lines had one or more tracks removed.
In a few cases new lines were built and existing lines received major upgrades — but these were clearly the exception to the overall industry trends.
So, when, after deregulation in the 1980s and unanticipated traffic growth toward the end of the 20th century, most railroads found themselves short of infrastructure — and struggling to maintain what they had, as the existing infrastructure was subjected to increased wear and tear.
In late 2007, a study commissioned by the AAR found that these railroads needed an additional $148 billion in infrastructure to meet current and anticipated demands and that railroads could only meet some of those costs, with the rest having to come from public funding.
In many countries around the world, railroad infrastructure is seen as an investment in the economy, just as are highways and airports. In most of those countries, the major railroads are either government owned or operated or run by government-supported corporations.
In the United States, however, railroads were always private industries. And, they have fought fiercely to remain that way. In fact, for most of the 20th century, most larger railroads would have rejected public funding for fear that accepting such funds would diminish their decision-making ability.
That view changed rather abruptly in the past decade, as these railroads found themselves having trouble meeting customer demands. But, with a lack of a unified transportation policy that sees railroads as part of an integrated transportation system, federal money mostly came in the form of a few grants here and there.
THE STATES STEP IN
It was the states that ended up stepping in. In states ranging from California to North Carolina and Pennsylvania to Florida, states began focusing on the development and expansion of rail corridors. (New York and New Jersey have long been leaders in rail transit of all types.)
What these states wanted was to be able to run more passenger trains — on tracks that already had freight traffic, and sometimes a few long-distance Amtrak trains.
Though there has never been an absolute distinction between intercity trains and commuter trains, many of these projects blurred the distinction even further.
Commuter trains have normally been identified by a few characteristics: closely spaced station stops; cars with multiple large doors to facilitate quick loading and unloading at stops; and densely spaced seating, which put the emphasis on maximizing passenger loads, rather than passenger comfort and amenities.
But, if you run hourly service in a corridor that includes several major cities, are these commuter trains or intercity trains? Certainly some passengers will use them to commute to work, as well as for other travel.
How did the states get the freight railroads to accept these trains? They invested heavily in infrastructure.
Lines were double-tracked. Sidings or cross-overs between tracks were added. Signal systems were added or improved. Grade crossings were either upgraded to more safely handle fast-moving trains or were closed.
In some cases, the role of the passenger train operator being a tenant on the freight train line was reversed. The commuter systems bought the rail line and took over track maintenance and dispatching, while allowing the freight railroad to continue to run trains on the line. In this case, the freight railroad found itself relieved of paying property taxes on the now more valuable infrastructure, only paying use fees for the trains that it did operate.
CITIES LOOK INWARD
All over America, in cities with massive traffic congestion — and that now includes almost all bigger cities — people from mayors to transit advocates suddenly became aware of unused or underutilized rail corridors. If the corridor is largely intact but currently totally unused, the community is ahead of the game.
If there are still tracks there, connected to part of the national rail network, that's another plus. In most cases, it's much easier to rebuild existing track than to have to start from scratch. If you have usable track, even if it is in bad shape, you can bring in track machines and supplies, such as new rail and gravel ballast — by rail.
But, often, the urban and suburban rail corridors are still being used by a freight railroad, even if, in some cases, the volume of freight traffic is so low that the line sees at most one freight train per day. If that's the case, time separation of commuter and freight operations is possible. That means that the line can be used by electrified light rail vehicles or non-FRA-compliant diesel equipment. (The Federal Railway Administration (FRA) sets the standards for what types of passenger equipment are allowed to mix with freight traffic.)
Several U.S. transit systems currently use time separations, with freight trains only venturing onto the line after the transit system has shut down for the night. Two different operations in the San Diego area — the San Diego Trolley and the Oceanside-Escandido Sprinter service — fit into this category.
But, if there is still a substantial amount of freight traffic on the route, bringing in commuter rail becomes much more complicated. Most freight railroads are amenable to commuter operations, as long as they don't substantially interfere with freight operations and as long as the freight railroad is adequately compensated. That compensation may include track and signal upgrades paid by the transit system — upgrades that also help move freight trains.
For the transit system, the most important question is whether the line is already double track or can easily be converted to double or even track. Not only does double track allow bi-directional operation at the same time, but it also allows one train to overtake another, including a disabled train. Yes, all of those actions are possible on a single-track line, but they have to take place at specific siding locations and are usually much more time consuming.
Operating speed is another important question. For higher speeds, the FRA requires that the line be signaled.
LIABILITY
But, ultimately, one of the biggest questions is one of liability. Any accident on a rail line carrying passengers can be devastating. Who pays if the freight railroad is found to be at fault?
Massachusetts is currently trying to implement commuter rail between Worcester and Boston on tracks currently owned by CSX, but so far the plan is at an impasse due to the liability question. CSX is willing to sell the state the right of way, but only on the condition that it be allowed to continue to operate some freight trains — and that it be absolved of liability if a freight train injures passengers.
Massachusetts legislators are struggling with the issue. While they concede that the likelihood of a major accident is remote, they also recognize that if such an accident happened, it could potentially leave the state facing huge bills.
WHAT DO FREIGHT RAILROADS WANT?
Assuming that questions of liability can be resolved, what do freight railroads want in order to let a commuter operation use its tracks?
They want to come out ahead on infrastructure. Most of the improvements needed to run commuter trains — signals, double or triple tracking, improved grade crossings — also help the railroad's freight trains operate safer and faster.
THE BOTTOM LINE
One of the reasons that most freight railroads are unwilling to say much about possible commuter rail operations on their lines, other than that such an operation should not have any negative effects on existing freight operations, is that every rail corridor is different — as is each proposed commuter rail operation.
Rail lines have different amounts and types of traffic. If a line has a substantial number of rail-served industries, switching those industries consumes a large amount of track time, requiring that these local freights work off a main line track, other than the one used for through traffic and potential commuter trains.
If your city or metropolitan area has one or more freight rail corridors that coincide with commuting patterns, consider yourself lucky. But, don't assume that putting commuter trains on these lines is going to be easy.
Journalist Ernest H. Robl is the author of more than 50 magazine articles on railroad and rail transit topics.
author: By Ernest H. Robl