Intermodal traffic rose 20.3 percent in the third quarter from a year earlier, driven by a 28.1 percent rise in import-powered international loadings, according to the Intermodal Association of North America.
In all, IANA said railroads carried 3.603 million revenue loads of containers and trailers in the July-September period, up from 2.995 million in the 2009 quarter.
Domestic volume that competes with trucking grew 11.7 percent to 1.591 million units, most of which was the large-capacity 53-foot containers that have become the standard domestic intermodal box size along with some trailers. International shipment of 2.012 million marine containers is mostly in 40-foot units, but includes 20- and 45-foot boxes.
By The Numbers: U.S. Intermodal Shipments.
While the growth in domestic intermodal means it continues to outpace the economy and take transportation market share away from all-highway moves, IANA said international volume was so strong that it hindered restocking the North American domestic container fleet. Imports dominate the international traffic, and this year has often seen ship lines quickly unload their marine boxes so they could send empties back to Asia to reload.
Railroads and other firms that provide domestic containers had ordered more built at factories in Asia, but those 53-footers had to come back in on the same containerships that were usually full of marine containers carrying consumer goods.
“While many domestic container fleet operators have placed orders for new containers, containership capacity constraints have prevented many of these orders from being filled,” IANA said. “As a result, there are fewer domestic containers available to handle surging demand.”
The trade group said that could also be why intermodal trailer volume grew 8.5 percent in the quarter. Rail loadings of the more efficient, stackable containers increased 13 percent, but trailer traffic strengthened during the time that additional domestic containers were slow to come into the North American fleet.
The third quarter included what have been the highest-volume weeks so far this year, and industry officials say traffic remained around peak-season levels throughout October.
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