because rail uses far less fuel and manpower
per ton-mile. Note, too, that the prospects for
increasing carrying capacity using sophisti-
cated information technology are greater for
rail than for highways because rail systems are
inherently less complex than road systems and
access to rail is easier to model and to control.
dal transportation in particular goes further
replete with what economists call "externali-
ties" the costs of congestion, pollution and
energy insecurity that are borne by third par-
ties rather than by the buyers and sellers of
the shipping services. A single intermodal
freight train can displace as many as 300 in-
tercity trucks from the highways, and reduce
fuel consumption by 75 percent in the pro-
cess. One study (admittedly, commissioned
by the railroad's trade association) estimates
that if 25 percent of freight volume were
shifted from trucks to rail by 2026, commut-
ers could save an average of 41 hours a year in
time spent in traffic. And, of course, since
railroads are far more fuel-efficient than
trucks, the shift would reduce both local air
pollution and greenhouse gas emissions.
Domestic intermodal rail traffic has quadru-
best hope of expanding future shipping ca-
pacity without pouring hundreds of billions
of dollars into highways. But a variety of fac-
tors now constrain it.
over) effective maximum capacity because
tonnage had increased so rapidly in the previ-
ous decade. Railroads have responded by ac-
celerating investment in double-track lines,
modern signal systems and rail beds capable
of supporting faster speeds. But they are still
behind the demand curve.
But the junctions or terminals at the ends of
the corridors (usually in urban areas) are
highly congested and thus act as bottlenecks.
Often, the simplest way to increase corridor
capacity would be to double-stack standard-
ized containers on the rail cars. But on the
older rail networks especially those in the
eastern half of the country double-stacking
will not be possible until tunnels are enlarged
and bridges are raised to accommodate taller
trains.
investing with this goal in mind. But the sums
involved are daunting: the American Society
of Civil Engineers estimates that some $200
billion in improvements will be needed to
meet demand for rail services over the next
quarter-century. And in the post-financial-
meltdown era of tight credit, that amount of