It's been a boon for the Class I freight railroads, which have taken market share from trucking companies that have ceded the majority of the length of a typical intermodal haul. Last year, a record 13.5 million containers and trailers were transported intermodally in the U.S. with the help of rail, according to the Association of American Railroads, and intermodal is now the single-largest source (22 percent) of the freight rail industry's revenue, offsetting a steep decline in coal shipping.
"It's one of our strategic focus areas, and it has been for a number of years," said Erik Hansen, vice president of intermodal for Kansas City Southern. "We try to leverage growth of this particular segment in order to grow the company overall."
Fredrik Eliasson, executive vice president and chief financial officer of CSX, Kansas City Southern's competitor to the east, expects first-quarter increases in intermodal to help offset declines in coal and slower growth in crude-by-rail, contributing to double-digit earnings growth for 2015.
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"We have just about gotten back to where we were in 2007 before the recession," said Edward Hamberger, chief executive of the Association of American Railroads, referring to the railroad industry's recent return to overall peak volumes. "The fastest-growing piece of the business is intermodal."
But railroads aren't the only transport companies focusing heavily on the segment. Trucking and marketing companies including J.B. Hunt, Hub Group and Swift Transportation have also brought resources to bear.
Privately held Schneider, one of the largest trucking companies in the U.S., works with railroad operators from BNSF to Kansas City Southern to CSX. The company has been increasing loading lanes at terminals and focusing on new regions like the Southeast, where expansion is fastest. It's also been buying up more containers and truck chassis.
"Intermodal is one of the fastest-growing segments for Schneider," said Bill Matheson, president of Schneider Intermodal. "We believe the intermodal marketplace will grow 8 percent in 2015."