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Transit 101: Commuter Rail

Transit 101 is an occasional series that will focus on the history and technology of modern-day public transit systems. The current topic is a primer on the various modes of rail transit.

Part I: Streetcars and Interurbans
Part II: Heavy Rail and Light Rail
Part III: Commuter Rail
Part IV: Intercity Rail and High-Speed Rail

Metra gallery coaches being pulled by a diesel locomotive (Photo: Keeleysam /

The past two installments of the Transit 101 series have focused on transit systems that primarily operate on dedicated tracks (either on their own rights-of-way or on shared rights-of-way with street traffic) that provide frequent transit service within a metropolitan area. Commuter rail differs from these modes in a number of aspects. The American Public Transit Association defines commuter rail as follows:

Commuter Rail is a mode of transit service (also called metropolitan rail, regional rail, or suburban rail) characterized by an electric or diesel propelled railway for urban passenger train service consisting of local short distance travel operating between a central city and adjacent suburbs. Service must be operated on a regular basis by or under contract with a transit operator for the purpose of transporting passengers within urbanized areas, or between urbanized areas and outlying areas. Such rail service, using either locomotive hauled or self-propelled railroad passenger cars, is generally characterized by multi-trip tickets, specific station to station fares, railroad employment practices and usually only one or two stations in the central business district. Intercity rail service is excluded, except for that portion of such service that is operated by or under contract with a public transit agency for predominantly commuter services. Most service is provided on routes of current or former freight railroads.

A Brief History

Photo: Mike Crowe

Wikipedia has a comprehensive article about the history of rail travel in general. Precedents for rail technology date back to the Diolkos Wagonway in ancient Greece, in which wagon wheels fit into a grooved “track” in the road. The earliest true railroads in Europe date to the Middle Ages, in which vehicles were manually pushed along wooden rails. In the late 1700’s, iron was used to plate the wooden rails. By the mid-1800’s, the iron-plated wood rails began to be superseded by rails made entirely of iron and then steel.

Rail transportation, which so far had been reliant on manual labor provided by humans or animals, experienced a revolution in 1804 when the first steam-powered locomotive was demonstrated by Richard Trevithick in Merthyr Tydfil, United Kingdom. Despite some initial technical difficulties, the advent of the passenger railroad helped spur the Industrial Revolution in the UK and around the world, and permanently changed the way people lived and traveled. Prior to the development of the railroad, most people commuted only as far as they were willing to travel by foot or on horseback, and generally spent their lives near their place of birth. The railroad made it possible, for the first time in history, for large numbers of people to travel vast distances at speeds that had previously been unheard-of.

In the United States, the railroads made it possible for the young nation to rapidly expand to the west, and contributed directly to the growth of many major American cities. Chicago is the nation’s greatest example of railroad-fueled urban growth, as the city’s strategic location on a low subcontinental divide between the Great Lakes and Mississippi River watersheds made it the nation’s largest inland transportation hub. In the mid 1800’s, Chicago was a motley collection of log cabins in a swamp on the edge of Lake Michigan. By the 1890’s, Chicago was considered likely to surpass New York City as the nation’s largest. (New York at this time consisted only of Manhattan and parts of the Bronx; some historians argue that the rise of Chicago and its threat to New York’s dominance led directly to their decision to annex Brooklyn, Queens, and Staten Island to form the five boroughs in 1898.)

Throughout the country and beyond, intercity railroads soon began offering “commuter” service to nearby towns and cities. Communities grew up along the commuter rail lines and become America’s first bedroom suburbs, allowing workers to work in the city center but live in a more “rural” location with its real and perceived benefits. Many of these railroad suburbs now exist as wealthy communities with their own downtown business districts centered around the commuter rail station; examples include Highland Park and Lake Forest outside of Chicago, White Plains outside of New York, and Berwyn outside of Philadelphia.

Cincinnati had its own commuter rail lines serving the suburbs and nearby cities. In 1933, many of them consolidated their downtown terminals at Cincinnati Union Terminal, but by the late 1930’s, highway construction and the rise of the automobile was already taking its toll. Passenger rail service in Cincinnati declined throughout the 1940’s and 1950’s. Cincinnati retains some intercity rail service in the form of Amtrak’s Cardinal, but commuter rail has been long extinct. In addition to Union Terminal, former railroad depots in Glendale and Silverton are among the only present-day reminders of its existence.

Union Terminal, prior to the demolition of the concourse. (Photo: Jack Klumpe / The Cincinnati Post)

Elsewhere in the country, commuter rail systems in major cities saw ownership and operation transferred from mainline railroads to public mass transit agencies. The Long Island Rail Road (LIRR), the nation’s oldest railroad still operating under its original name and charter, is now a division of the Metropolitan Transportation Authority (MTA). The commuter lines of the former New York Central Railroad are now another MTA division, the Metro-North Railroad. In Philadelphia, the commuter lines once operated by the Pennsylvania Railroad and the Reading Railroad now fall under the umbrella of the Southeastern Pennsylvania Transportation Authority (SEPTA). Chicago’s commuter rail lines, with the exception of the South Shore Line, are now operated by Metra.

In more recent years, some cities have launched new commuter rail systems. These systems range from a single line, such as Portland’s West Side Express Service, to a comprehensive system such as Metrolink in Los Angeles.

Here in Cincinnati, the 2002 Metro Moves plan proposed commuter rail service from Union Terminal to Lawrenceburg, Hamilton, and Milford. A modified version of the Milford line now forms a portion of the Eastern Corridor, but as of this writing, progress remains stalled amid questions of its route and mode of service.

Characteristics of Commuter Rail

As opposed to the other modes of rail travel we have discussed so far, commuter trains fall under the jurisdiction of the Federal Railroad Administration, and often operate on the same tracks used by mainline passenger and freight trains. Commuter rail lines may be operated by a public transit agency, or a contract carrier such as Amtrak or other railroad such as Union Pacific. (As a side note, some rapid transit systems also operate under FRA jurisdiction because of track connections to mainline railroads or other factors. Examples include the PATH system, the Staten Island Railway, and the NJ Transit River Line. However, these are rare exceptions.)

Aside from FRA jurisdiction, a number of factors make commuter rail distinct from other modes of rail transit we have discussed so far:

Frequency of Service: Whereas streetcar and rapid transit service (either light rail or heavy rail) generally operate based on headways, or number of trains per hour, commuter rail generally operates on a fixed schedule that is published on a timetable. For example, a passenger can head into a subway station and, depending on the system and the time of day, generally wait anywhere from three to fifteen minutes for a train at most. Commuter trains may be scheduled every hour or more, necessitating the passenger to consult the schedule and make an effort to be at the station in time for the 6:35 train, for example.

A portion of the timetable for Metra's Union Pacific North Line

Long Island Railroad electric multiple-unit train (Photo: Adam Moreira / Wikimedia Commons)

Some commuter rail lines in the Northeast have service frequencies that approach that of a rapid transit line, but these generally occur where multiple rail lines share a single trunk line before branching to their respective destinations. Examples of this type of frequent service include the Long Island Rail Road between Penn Station and Jamaica Station in New York, and along the Center City Commuter Connection, a tunnel through downtown Philadelphia opened in 1984 to connect the two major divisions of that city’s commuter rail system.

Rolling Stock: As with other forms of rail transit, rolling stock varies widely depending on the particular system. In the New York City region, Metro-North and the Long Island Rail Road operate electric multiple-unit (EMU) trains using a third rail power supply, making them essentially larger versions of subway trains. SEPTA in Philadelphia runs EMU trains under overhead catenary, while NJ Transit covers the gamut from EMUs to passenger coaches pulled by electric or diesel locomotives. Most commuter trains outside the Northeast consist of passenger coaches hauled by diesel locomotives.

The Chicago and North Western Railroad pioneered the concept of push-pull operation, in which the locomotive is controlled from a cab car at the opposite end of the train. In pull mode, the train is simply pulled by the locomotive. In push mode, the train operates “backwards”, being pushed from behind by the locomotive, which is controlled from the cab car at the “rear” of the train. This eliminated the need for complicated switching maneuvers at the downtown terminal.

The interior of a bilevel coach on NJ Transit's Northeast Corridor Line

The Chicago and North Western also was one of the first railroads to develop the gallery car, which features multiple levels of seating. Today, commuter railroads may use single-level railcars (particularly where vertical tunnel clearances may be a limiting factor), gallery cars, or bilevel cars. Innovations such as push-pull operation and bilevel railcars have spread throughout the world and are now considered standard practice.

Lengths of commuter trains can very widely, ranging from the single-car Princeton Dinky shuttle train to trains consisting of a dozen or more passenger cars plus one or more locomotives.

On-Board Amenities: Commuter trains typically feature improved passenger amenities compared to light rail or heavy rail transit. These amenities include more comfortable seating, luggage racks, and on-board washroom facilities. Other amenities such as wifi access and power outlets for laptop computers may be found. Consumption of alcohol is also permitted on many commuter rail systems, and Metro-North’s New Haven Line even has a bar car. For over a hundred years, the Long Island Rail Road has been operating the Cannonball, a premium express train between New York City and the Hamptons that features in-seat beverage and snack service during the summer months.

Service Patterns: As opposed to rapid transit service, which generally passes through the central business district of a city en route from one terminal to another, commuter trains usually begin in the suburbs and terminate downtown. A notable exception to this characterization is the SEPTA Regional Rail system in Philadelphia, in which trains usually run from one suburban terminal to another via a downtown tunnel built in 1984. A train beginning its trip at Chestnut Hill East may continue on to Elwyn via 30th Street Station, Suburban Station, and Market East Station in downtown Philadelphia.

Market East Station in downtown Philadelphia

Fares and Fare Collection: As a general rule, fares on rapid transit systems tend to be a flat fare, paid upon entering the station. (Some rapid transit systems, notably the Washington Metro, employ a zone-based fare system more akin to that of a commuter railroad.) Commuter railroad fares are distance-based, with destinations usually grouped into fare zones. Shorter trips require lower fares, and vice-versa. There may also be a surcharge for travel in the peak-direction during rush hours. Tickets are typically purchased in the station from an agent or via a vending machine, and collected on board by the train crew. Whereas a subway train may be operated by one or two crew members, a commuter train is operated by an engineer, a conductor, and up to several assistant conductors depending on the passenger load.

Distances Traveled: Distances of typical commuter rail lines range from only a few miles in the case of SEPTA’s Chestnut Hill West line, to up to almost a hundred miles in the case of the South Shore Line and LIRR’s services to eastern Long Island.

The following video shows the ride on SEPTA’s R7 Trenton line between the North Philadelphia and 30th Street Stations:

Aside from the now-stalled Eastern Corridor project, there are currently no active proposals for commuter rail in the Greater Cincinnati region. The most likely destinations for commuter rail service in Cincinnati include Lawrenceburg, Milford, Hamilton, and Dayton. Other nearby cities such as Columbus, Indianapolis, Louisville, and Lexington are at the upper end of feasible distances for commuter rail travel, but may see future connections to Cincinnati via intercity rail and high-speed rail, which we will discuss in the next and final installment of this series.