Interurban

In Australia, interurban is a general term for intercity rail.

An interurban, also called a radial railway in parts of Canada, is a streetcar line running between urban areas or from urban to rural areas. The term was mostly used in North America. The lines were mainly electrified in an era when steam railroads had not yet adopted electricity to any large degree.

The first interurbans were constructed in the 1880s, but most were constructed between 1900 and 1908, with few being constructed after that point. From approximately the end of the First World War the industry was in decline, accelerated by the growth of the private automobile; the Great Depression of the 1930s drove most into closure. Only a couple survived beyond the 1960s.

To minimize cost of construction, an interurban typically ran along public right-of-way, either next to a public highway in rural areas, or within city streets in urban areas. It was somewhat less common for interurbans to have lengthy stretches of private right-of-way. Occasionally interurbans were operated along mainline steam railroads. Fares were cheaper than steam railroads and service was more frequent but typically slower. Due to the characteristics of the electric motor, interurbans could operate on steeper grades, going where steam engines could not.

With the demise of the interurban, many routes were taken over by intercity bus services. Most local intercity services have since been discontinued; buses now typically run express between cities. A few interurbans, built to rather high standards, have survived, as have several that still operate only freight service, but the vast majority are long abandoned.

Definition of "Interurban"

Real-world lines fit on a continuum between wholly urban street railways and full-fledged railroads. George W. Hilton and John F. Due, in The Electric Interurban Railways in America, define an interurban as a system which shares most or all of four characteristics:

Electric power
Passenger service as primary emphasis
Heavier, faster equipment than urban streetcars
Operated on street trackage in cities but on roadside tracks or private rights-of-way in rural areas

The definition of "interurban" is necessarily blurry. Some streetcar systems evolved into partly interurban systems with extensions or acquisitions, while other interurban lines became, effectively, light rail systems with no street running whatsoever, or became primarily freight-hauling railroads with a progressive loss of passenger service.

Another distinction is made between "interurban" and "suburban". A suburban system is oriented toward a particular city center in a single urban area, serving primarily commuters who live in the suburbs of a city. An interurban is more like a regular railroad local train service, moving people from one city center to another with no single center. However, unlike a local train, the interurban serves a smaller region and has more frequent service, and is oriented to passenger rather than freight service, although some small-load freight service was common, especially in the days before trucks (lorries).

Interurban technology

In general, interurbans operated with technology somewhere between that of a streetcar line and a full-scale railroad. The vast majority of interurbans were electrified, utilizing overhead trolley wire, pantograph, or third rail carrying 600–1500 volts DC.

Electrification

Most interurban railways in North America were electrified using low-voltage direct current systems popular with street railways.Hilton and Due, pp. 53-65. This enabled interurbans to use urban street railway systems with ease. However, these systems had difficulty in maintaining voltage over long distances. Thus, interurbans developed the practice of generating power at higher voltages and stepping down power to the 600 volts needed to power the cars at substations spaced out along the line. By 1905, 600 volts had become the industry-wide standard.

The interurbans also had to develop their own powerhouses for electricity as there were few commercial power companies in existence at the time. Some of these power houses produced high-voltage AC power that would be stepped-down and converted to DC at the substations. Because of this choice, many interurban railway companies became electric companies.

Most power was distributed to the cars using overhead trolley wires or pantographs. Some companies preferred outside third rail. Third rail was cheaper to maintain and improved conductivity, but it was more expensive to construct as it did not mitigate the construction of transmission lines and poles. Third rail was also more dangerous to trespassers and animals. Also, in the winter, third rails were difficult to keep clear of ice.

In 1904, a single-phase alternating current system became available and was distributed by Westinghouse and General Electric. But the system soon proved expensive to maintain and operate, and it increased wear and tear on equipment and track. It was a short-lived experiment and none were installed after 1910.

Another experiment in electrification came in 1907 with high-voltage DC (1200 volts). This system was allowed for easy conversion from other DC systems and was cheaper to maintain. But it was developed so late that few railways adopted it.

Gauge

Most interurbans were built to standard gauge, but there were a fair number of exceptions. Interurbans often used the tracks of existing street railways through city streets, and when those street railways were not built to standard gauge, the interurbans had to use non-standard gauges as well or face the expense of building their own trackage through urban areas. Many municipalities had ordained the use of non-standard gauges so that railroad freight cars could never be switched on the public streets.

Passenger service

Freight service

United States

In the late 1890s, electrified systems called streetcars, which had been developed by Frank Sprague, expanded rapidly. By 1900, just over 2,100 miles of track had been laid, and by 1916, at their peak, over 15,500 miles were in service. Most of the interurban track that had been laid was located in Ohio and Indiana; both states had 3,000 miles of track. In Michigan and Illinois there was another 2,000 miles of track which was interconnected. In Texas and in California thousands of miles of additional track was also laid down by different companies. In Central Virginia, interurban lines connected City Point and Hopewell with Petersburg, and Petersburg with Richmond. Another connected Richmond with Ashland.

In the early 1900s, interurban transportation was very popular in both rural areas and cities. Although slower in speed than steam driven passenger trains, the interurban system made up for speed by increased frequency of service. After 1910, the popularity of the Ford Model T automobile began to diminish the interurban passenger load, and during the 1920s, many interurban systems were declared bankrupt. As a result of this shift in transportation methods, the small and unprofitable lines were discontinued. By the 1930s, the interurbans began to disappear, although some of their rail lines were taken over for the use of freight drawn by steam engines. Most were replaced with buses. By the 1960s, very few lines remained; the Pacific Electric Railway in California was abandoned in 1961, and the Chicago North Shore and Milwaukee Railroad near Chicago in 1963.

Remaining lines

Few historic interurban lines are still operated in their original form, although a number of more recently-constructed transit lines could be considered interurbans by Hilton and Due's standards above.

The Philadelphia and Western Railroad is now SEPTA's Norristown High Speed Line, and has many characteristics of a rapid transit system, including full grade separation and high platforms. The Chicago South Shore and South Bend Railroad is now NICTD's South Shore Line, and still includes a street running section in Michigan City, Indiana, but has many characteristics of a commuter rail operation, including sharing the trackage of the Metra Electric Line (formerly the Illinois Central Railroad) into downtown Chicago.

In Los Angeles, the LACMTA Blue Line uses much trackage that was the Pacific Electric's route between Los Angeles and Long Beach. There is street trackage at both the Long Beach and Los Angeles ends of the line, and a short subway section at the Los Angeles terminus.

Other lines that have some characteristics of an interurban include:

The Green Line "D" Branch in Boston, a streetcar line on a grade-separated right-of-way formerly belonging to the Boston and Albany Railroad, a steam railroad
The Ashmont-Mattapan High Speed Line in Boston, a streetcar line on a right-of-way formerly belonging to the Dorchester and Milton Branch Railroad, a steam railroad
The IRT Dyre Avenue Line in New York City, a rapid transit line on a section of the former New York, Westchester and Boston Railway, an interurban

The Iowa Traction Railroad (former Mason City and Clear Lake Railway) still operates electric freight service. Several others, such as the Cedar Rapids and Iowa City Railway and Central California Traction Company now operate as diesel locomotive powered freight lines. The Chicago South Shore and South Bend Railroad operates freight service along the passenger South Shore Line.

Other portions of interurbans remain in service as parts of regular freight-hauling railroads; for instance, portions of the Sacramento Northern Railway were operated by the Union Pacific Railroad. The longest surviving portion of the Sacramento Northern is now owned by the Sierra Northern Railroad.

Canada

The first interurban line in the world opened in 1887 and ran between St. Catharines and Thorold, Ontario, Canada. Not only was this the first interurban line in the world, but it was also one of the first commercially successful implementations of electric streetcar in the world.

In Southern Ontario, intercity streetcar lines were called radial railways, because their routes generally radiated from a central city. The longest routes from Toronto included one running to Lake Simcoe and another to Guelph. A portion of one of these lines is preserved and plays host to a working museum of streetcars and other transit vehicles at the Halton County Radial Railway in Rockwood. A notable feature of Toronto's radial railways was that because the city streetcar tracks of the Toronto Railway Company (later taken over by the Toronto Transportation Commission) were built to a wider gauge (which is still used to this day), radial cars from the outlying areas could not pass the city limits, requiring passengers to change trains.

Some of the closer sections of Toronto's radial railways were assimilated into the city's streetcar network, and with the city's expansion, some communities once linked by radial railway now have relatively central stations on the Toronto subway. On a regional level, GO Transit's commuter railway network is designed on a similar radial principle, though it uses much heavier-capacity mainline trains.

There were also significant radial systems operating from Hamilton, St. Catharines, Windsor, and throughout the Grand River Valley, the last of which may see a revival should Grand River Transit obtain funding to build a light railway between Waterloo, Kitchener, and eventually Cambridge, running partially on the tracks of the former Grand River Railway. Hamilton and the Niagara Region are also investigating the possibility of reviving former interurban railway routes as modern light rail.

Europe

In Europe, lines that fit the interurban definition were rare historically. More common were either wholly urban, street-running tram systems or light rail systems operating wholly on dedicated rights of way. See tram-train for information about modern European systems running on the streets in cities but on railway lines outside them.

Notes

References

External links

Interurbans: The technology of economical local transport in the United States
Dave's Electric Railroads, a collection of electric railroad, interurban, and streetcar photography from many eras
Principle (sic) Interurban Car builders of the U.S
Roster of Preserved North American Electric Railway Cars
The Last Interurbans

Interurbans

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