Intermodal transportation, specifically rail intermodal, has emerged as the fastest-growing major rail traffic segment over the past 25 years. This method involves the movement of shipping containers and truck trailers by rail, revolutionizing the transportation industry. It’s fascinating to consider that many of the products found on retailer shelves have likely journeyed on an intermodal train. Freight railroads, in collaboration with other transportation providers, play a significant role in carrying nearly 61 tons of freight per American each year, showcasing the extensive reach and impact of intermodal transportation.
In 2022, U.S. rail intermodal volume reached a staggering 13.5 million units, making it the most significant contributor to revenue for major U.S. railroads, surpassing all other rail traffic segments. Reflecting its importance in international trade, approximately half of rail intermodal volume comprises imports or exports. Rail intermodal is characterized by the long-haul movement of shipping containers and truck trailers by rail, which is further complemented by a truck or water movement at one or both ends. This mode of transportation combines the best attributes of different modes to achieve efficiency and cost-effectiveness. It serves as a reliable means of transporting a wide range of goods that Americans utilize daily, from products on retailer shelves to industrial and agricultural items like auto parts and grain.
U.S. railroads have established the world’s most advanced intermodal network, with Chicago and Los Angeles/Long Beach emerging as the top U.S. metropolitan areas for intermodal volume. The success of major intermodal markets relies on their large populations and extensive highway feeder systems. Understanding that effective intermodal corridors necessitate sufficient line haul and terminal capacity to maintain smooth train operations and avoid congestion or delays, U.S. railroads have invested substantial resources to create an unparalleled intermodal network. They have maximized existing capacity and allocated tens of billions of dollars toward new infrastructure and equipment specifically designed for intermodal operations, including state-of-the-art intermodal yards.
The investments made by freight railroads in their intermodal networks have produced a positive cyclical effect. The surge in intermodal growth has prompted further investment by freight railroads to accommodate the increasing demands of customers. A significant contributing factor to this growth is the rise in container usage. Containers accounted for 47% of intermodal volume in 1990, 69% in 2000, and a remarkable 92% in 2019. Unlike trailers, containers can be “double stacked,” allowing for optimal use of space and ensuring sufficient traffic density to keep rail intermodal cost competitive with all-truck movements. Over the years, freight railroads have invested in elevated railroad tunnels to accommodate the stacking of containers, further enhancing the efficiency and capabilities of intermodal transportation.