From the rail perspective, 3Gi is a reverse of the conventional landbridge service run from the west coast.  

The Reverse Landbridge Service

In the intermodal context, a landbridge, or land bridge service refers to the overland rail portion of an ocean container shipment. The most common application in the USA is an Asian container import landing at a west coast port, where it is loaded on rail to its final destination on the west coast (mini landbridge), or to an inland destination (micro landbridge). The reverse landbridge is a service in the opposite direction, from the east coast or the gulf coast to an inland mid-country market. They serve the reverse role of the current trans-continental landbride for containers to/from Asia, except on a smaller scale.   Instead of calling on east coast ports, containers are shipped through the Panama Canal to the east coast and then shipped by rail or truck to points west  The challenge is in the cost competitiveness of the rail reverse mini landbridge, given the close proximity of the markets to the ports.

There are two unique aspects to the reverse landbridge, that sets it apart from its west coast cousin, other than the directional difference.

1. Trans-Panama All-Water Services - The promise of greater lift capacity after the Panama Canal's expansion and the rise of all water routes to the east and gulf coasts, provide the eastern railroads with added mid-country reach, allowing them a competitive platform with the western railroads.     
2. Short Haul Dis-economies - Reverse landbridges from the east and gulf coasts service "mid-country" markets which have traditionally been served by truck, due to the relative short haul.  Whereas, traditional intermodal services are most economical over long hauls, for which the long distances from the west coast to markets on the east coast and the American heartland, are ideal.  
   

New Intermodal Investments in Support of the Reverse Landbridge

A recent set of investments made by eastern and and central railroads form the foundation for the development of 3Gi reverse lanbdridge services.  These include  the Heartland and Crescent corridors (Norfolk Southern) as well as the Southeast Triangle (CSX).

 Examples of Reverse Landbridge Services from the East Coast and Gulf Coast

Aggregate Densities to Compensate for Short-Haul Dis-economies

Concentrate reverse landbridge services between efficient ports and large markets.  Aggregate services from the most efficient ports where a higher ratio of goods can transition between international containers and domestic shipments in shorter timeframes.  And limit operations at the market end to a single logistics park so as to increase service velocity, reduce local shuttle costs, and improve equipment utilization efficiencies. 

Utilize New Technologies to Maximize Throughput at Load Centers

Utilizing superior technologies that result in significant throughput increases (2 to 3 times) per acre over more traditional operations.  Moving from rubber tire gantry (RTG) and straddle crane technologies to wide-load gantry cranes or rail-mounted gantry (RMG) cranes is also critical.  RTG systems support building a single-unit train-to-truck, whereas RMG can straddle up to six rail lines, two or three truck feeder lanes, and up to 10 rows of stacked boxes.  These new automated technologies maximize movements between each mode, eliminating the need for chassis and hostlers, reducing operating costs, improving safety, reducing the acres needed, and increasing throughput.

Migration of Automation Standards and Protocols from Marine Terminals to Intermodal Yards

The large marine terminals are increasingly using highly automated protocols and standards to allow them a more efficient operation, including the ability to operate 24/7, a reduction in operating costs, and a more productive use of land for storing/stacking boxes.  Automation is achieved by using robotic gantry systems which utilize automated “container picking” and “container put-away” logic. These same standards should be applied at the intermodal load centers on either ends of the reverse land bridge service.