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Definition: Heavy Rail
Heavy rail refers to traditional high platform subway and
elevated rapid transit lines. Principal characteristics are operation over
rights of way that are completely segregated from other uses, with the track
placed in subway tunnels, on elevated structures, or on fenced surface rights of
way, free of grade crossings with roads. Trains consist of anywhere from two to
12 cars, each with its own motors, and drawing power from a third rail (or in
some cases from overhead wire). Boarding is from high platforms that are even
with the floor level of the car, allowing large numbers of people to enter and
leave rapidly. Before World War II, true heavy rail rapid transit systems
existed only in Boston, New York, Philadelphia, and Chicago. Since the war, new
systems have been opened in Cleveland, Baltimore, Washington, the San
Francisco-Oakland region, Los Angeles, Atlanta, and Miami, plus Montreal and
Toronto in Canada.
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An experimental modern rapid transit train running on an elevated line in New York. |
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Heavy rail systems are extremely expensive to build due to
the need to build tunnels, elevated structures, or other fully segregated rights
of way and to accommodate more gentle curves and grades than are needed for
light rail or streetcars. Given the high costs and the recent huge overruns of
the Los Angeles rapid transit construction, funding of new heavy rail systems in
the United States has become much less likely.
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