Intermodal Transportation Guide

Intermodal is the movement of freight in containers or trailers over two or more modes of transportation such as air, rail, truck, and ship.

While it can include any combination of these modes, the most common pairing is rail and truck, which will be the focus of this guide. In this scenario, the shipment travels by rail for most of its journey, and trucks provide drayage for the short-distance transport to and from the rail facility.

It should be noted that not all rail shipments are intermodal. There are other forms of freight rail transport (boxcars, hoppers, gondolas, etc.) that are made only for rail travel and do not convert for movement over the road.

North America boasts the largest and most efficient intermodal network in the world, valued at more than $40 billion dollars. This makes it a great option if you are a shipper whose supply chain runs through Canada, Mexico, or the United States.

In the U.S., the rail infrastructure that intermodal runs on is privately owned, operated, and maintained. This makes it unique compared to other forms of freight transportation such as ship and truck, which partly rely on public infrastructure. However, railroads are still subject to government safety and operational regulations which are overseen by the Federal Railroad Administration (FRA).

There are over 140,000 miles of freight railroad track in North America, including 6 Class 1 Railroads, 22 regional railroads, and 584 shortline railroads. Most intermodal shipments travel on Class 1 railroads, which each service different regions.

Below are the 6 Class 1 Railroads and the territories they serve.

Intermodal shipments carrying consumer goods make up 48% of rail freight in the United States. But intermodal is extremely versatile and can move most commodities. Some common examples include electronics, agricultural products, clothing, vehicles, machinery, and construction materials. It can also accommodate specialized shipments like:

• Refrigerated and frozen goods in reefers (temperature-controlled containers)
• Liquids in tank containers
• Hazardous materials (hazmat)

The process your intermodal shipment goes through will differ whether it’s moving domestically or internationally.

Domestic Intermodal

These are the steps involved in domestic intermodal transportation:

Pickup & Origin Dray

A truck driver (also known as a drayage carrier) is dispatched to pick up an empty container and take it to the shipper’s location. For domestic intermodal, the most common container size used is 53’.

An empty container must be picked up first because most drayage carriers are power-only. This means they provide a truck tractor to haul the load but not the container or chassis.

These are two common methods for a shipper to load their freight once the truck arrives at their location:

• Live Load: The shipper loads their freight into the empty container while the driver waits.

• Drop and Load: Instead of waiting, the truck driver drops off the empty container at the shipper’s location and picks up a container that’s already been loaded. While the full container is in transit, the shipper loads the new empty container for pickup. This technique is used for large-volume shippers who need to turn multiple containers of freight in the same day.

Once the freight has been picked up, the drayage carrier transports it a short distance (usually less than 50 miles) from the shipper’s location to the intermodal terminal.

Rail Transportation

When the shipment arrives at the intermodal terminal, it is transferred from truck to train, then spends most of its journey being transported to its destination by rail.

There are two techniques of loading a shipment onto a rail car, based on the type of equipment used.

• Container on Flat Car (COFC): If the freight is loaded in a shipping container, the container is removed from the chassis and placed on a flat rail car. This is the more popular option because containers can be double stacked to provide additional capacity if needed.

• Trailer on Flat Car (TOFC): In some cases, a shipment is loaded into a trailer rather than a container. In this scenario, the entire trailer is detached from the back of the truck and loaded onto a flat railcar. Trailers do not have the ability to be stacked like containers.

Destination Dray & Delivery

Once the shipment arrives at the destination intermodal ramp, a drayage carrier is dispatched to pick it up. The driver then transports the freight from the rail terminal to the receiver’s location.

International Intermodal

Intermodal can be part of your international supply chain to transport cargo to and from ports. This is the process that intermodal shipments follow from arrival at the destination port to delivery at the final location. When moving from the shipper’s location to the origin port, the process is simply reversed.

Unload and Transfer

After arriving at the port, the container is unloaded from the ship and transferred to a rail car. The method used depends on the port’s intermodal capabilities and shipper’s needs:

• On-Dock Rail: If the port has on-dock rail facilities, the container is transferred directly from the ship to rail car instead of being transported by truck to an intermodal facility.
• Drayage: If the port doesn’t have on-dock rail, the container is picked up from the port by truck for drayage to the nearest intermodal facility or to a warehouse to be transloaded.
• Transloading: If the shipment is going to be transloaded, it will be picked up from the port by truck for drayage to a warehouse. Transloading involves unloading the contents of a 20’ or 40’ international container and reloading them into a 53’ domestic container.
  
  This is an optional step since international containers are compatible with the truck and rail equipment used in intermodal. The primary reason is to save on transportation costs by consolidating the cargo into fewer containers for the remainder of the shipment.
  
  Once the cargo has been transferred between containers, a truck picks the shipment up for transport to an intermodal facility.
  
  Before deciding to use transloading, it is important to make sure that the freight won’t exceed the weight limit once combined in the larger container. Transloading may also increase the risk of damage to the freight since it requires additional handling.

Rail Transportation

Once the container has been transferred to rail car, the rest of the move operates the same as a domestic intermodal shipment. The container spends most of its journey traveling by rail until it arrives at the destination intermodal terminal.

Destination Dray

Upon arriving at the intermodal terminal, the container is picked up by a drayage carrier who completes the delivery to the receiver’s location.

The two most up-to-date loading guides are published by the Association of American Railroads (AAR) and are considered the standard for intermodal shipments in Canada, the U.S., and Mexico. You can access both guides below:

• Intermodal Loading Guide for Products in Closed Trailers and Containers
• Rules Governing the Loading, Blocking, and Bracing of Freight in Closed Containers and Trailers in Intermodal Service

Individual rail lines may also have their own loading requirements, so it is important to check with your intermodal provider to make sure you are adhering to their rules. If you need additional assistance, many rail lines even offer training on how to properly load your container. Some examples are CSX Intermodal’s LEADs program (Load Engineering and Design Services) program and Union Pacific’s Shipment Quality Load Consulting Engineers.

Weight Limit & Distribution

The total weight limit for an intermodal shipment when moving over the road, (including container, chassis, and truck) is 80,000 lbs. To stay within the allowable range once the container is loaded onto the chassis, it is recommended that the total cargo weight remain under 43,500 lbs.

When loading the container, weight also needs to be distributed evenly, both from side to side and top to bottom. Be mindful of how the weight will be spread across each axel to ensure that it doesn’t exceed the weight limit. These are the maximum weights allowed for each axel:

• Steer Axel: 12,000 lbs.
• Drive Axel: 17,000 lbs. for single axel or 34,000 lbs. in tandem
• Trailer Axel: 17,000 lbs. for single axel or 34,000 lbs. in tandem

Securing Cargo

In addition to loading your cargo, you will need to secure it to make sure it remains stable for the duration of the trip. This is important both for the protection of your cargo and successful rail transit.

Loads that are not secured correctly can shift while moving and possibly cause derailments. Trains can also be delayed if they need to stop and reposition containers that appear to be at risk. Common signs of at-risk containers include leaning to one side and straining doors, indicating that there is excess weight concentrated there.

When loading your cargo, keep in mind that it should be:

• Properly braced to withstand consistent vibrations or sudden changes in speed or direction
• Secured so it will not shift vertically or horizontally during movement
• Positioned and secured so it doesn’t exert pressure on the doors, as they are not designed to act as a brace against shifting cargo

These are some common methods for securing cargo:

Blocking/Bracing: The purpose of blocking and bracing is to create a physical barrier that holds cargo in place during movement. Blocking prevents side to side movement and bracing keeps cargo from moving up and down. Some examples include:

• Floor Blocking: Lumber is arranged in configurations and nailed to the trailer floor to hold cargo in place.
• Cross beams: Boards are secured horizontally across the container to prevent movement forward and backward.
• Wooden Wedges: Right angle wedges are nailed to the floor of the container, with the angled edge facing the wall and the flat edge against the cargo to prevent movement.

Dunnage: This describes materials that are used to fill spaces between cargo units to both protect them and hold them in place. Some examples include airbags, rubber matting, plywood, and honeycomb panels.

Pallet/ Unit Securing: This securing method holds individual units in a shipment together, such as boxes on a pallet. Some materials that can be used to do this are stretch film, metal or plastic strapping, and cardboard corner or edge protectors.

Like all modes of transportation, you need to balance the pros and cons of intermodal to decide if it is the right fit for your business.

Benefits

Cost Savings
One of the biggest incentives for shippers to use intermodal is the possibility for cost savings. When shipping distances of 500 miles or more, intermodal can be less expensive than OTR trucking traveling the same distance. In fact, shippers who switch from trucking to intermodal for long-distance shipments save an average of 10-40%.

The savings come from economies of scale. A train can carry a ton of freight more than 470 miles by rail, which is 4x more fuel efficient than a truck. The increased fuel efficiency makes for lower operational costs, which results in a lower cost per mile when traveling more than 500 miles. However, intermodal is not ideal for shipments traveling shorter distances because the cost of drayage would negate the cost per mile savings of rail.

Reliable Capacity
A single train can carry hundreds of containers and is rarely low on capacity, which makes intermodal a good option for volume shippers. Containers can even be double stacked on rail cars for shippers who need more space.

Intermodal’s ability to move large volumes of freight also makes it a good alternative for shippers who are short on truck capacity. This scenario may become even more common in the future, as trucking capacity is expected to become tighter with the growing shortage of truck drivers. In 2021, the American Trucking Association reported the industry had a shortage of 80,000 drivers and predicted that number will double by 2030.

Sustainability
With increased fuel efficiency, intermodal is a more environmentally sustainable mode of transportation. It also cuts down on the number of vehicles on the road, since a single train can carry the equivalent of 280 truckloads.

Disadvantages

Accessibility
Freight pickup and delivery locations must be within 100 miles of an intermodal ramp to maintain the cost savings benefit of shipping by rail, which limits the number of shippers who can take advantage of intermodal.

Most ramps are located near densely populated cities where the shipping demand is higher, leaving many rurally located shippers out of range. To view the closest intermodal facility near you, reference this map on the Intermodal Association of North America(IANA) website.

Limited Flexibility
If your shipment requires flexibility or is time-sensitive, then intermodal may not be the best form of transportation for you. Shipping routes are physically limited to areas where track is laid and the transportation timeline is determined by the railroad’s schedule instead of your business operations.

It’s also impossible to reroute a rail shipment once it’s in transit. This creates inconvenience and possible delay if a shipper’s delivery location changes or there is rail congestion.

Speed
Since intermodal involves moving freight between multiple modes of transportation, the complexity can result in longer transit times. There are multiple factors that may cause a delay during the process:

• Equipment Shortages: Truck chassis (for drayage) and containers are essential to intermodal. Sometimes, this equipment may not be readily available in periods of high demand. When this happens, shipments must be put on hold until these assets become available.
• Driver Availability: Drivers are needed to perform drayage to and from the rail facilities. If the drayage company is short on drivers, you may have to wait until one is available to move your load.
• Route Interchanges: Depending on the route your shipment is taking, it may run through an interchange. These areas, where the train is transferred from one track to another, require additional time to make sure the train remains in position while being redirected.
• Derailments: The catastrophic derailments shown on the news are not the norm. In fact, most derailments that occur are as small as a single wheel becoming misaligned with the track. These minor derailments are not a major cause of concern but still require that the train be delayed while it is repositioned correctly.

Weight Capacity
To remain in compliance with government weight regulations, Both dry vans and trucks carrying intermodal containers must not go over 80,0000 lbs. However, an intermodal container and chassis are about 2,500 lbs. heavier than a dry van attachment so it can carry less weight in freight overall.

When factoring in the weight of the tractor, this means that a dry van can carry about 45,000 lbs. of cargo while an intermodal container can carry no more than 43,500 lbs.

When to Use Intermodal

Here are some quick guidelines to follow when deciding if intermodal transportation is right for your freight:

• The shipment is traveling 500 miles or more: If your freight is moving more than 500 miles, using intermodal could cut down on your overall transportation costs.
• Your pickup and delivery locations are within 100 miles of an intermodal facility: If either location is more than 100 miles away, the drayage costs will negate savings from using rail transportation.
• You need consistent capacity to ship large volumes: Shippers of all sizes can benefit from intermodal. But If you are a high-volume shipper, it can be especially helpful due to the large capacity available. Trains can carry multiple truckloads worth of freight in one trip and rarely run out of space.
• The overall weight of the shipment is 43,500 lbs. or less: 43,500 lbs. is the most that your freight can weigh to meet government requirements after factoring in the weight of the other equipment.
• You have a flexible pickup and delivery window: Since intermodal shipping time can be unpredictable, a flexible schedule won’t put you at risk of missing a deadline in case of delay.

Domestic Intermodal vs. OTR Trucking

In the logistics world, OTR trucking and intermodal are often compared because they are the most common ways to transport freight domestically. While it’s true that they can both move freight over land for long distances, each has their strengths and weaknesses depending on your needs. This blog details how to weigh the pros and cons of each for your business.

Intermodal Provider Asset Classifications

All intermodal providers are capable of coordinating and managing the movement of intermodal cargo but not all of them own transportation assets. These are the three most common asset classifications for intermodal companies:

Asset Based:
Asset based providers own all the non-rail assets involved in an intermodal move. This includes the containers used to transport customers’ freight and the chassis and tractors involved in drayage. But no intermodal provider can be 100% asset based. The rail portion of transport means they must rely on resources owned by private rail companies like rail terminals, tracks, and trains for part of the service.

Asset-Lite:
Asset-lite providers own some of their own containers and dray equipment, but it’s not always enough to cover all the freight they are moving. When there is more demand than they have capacity to handle, an asset-lite provider must lease chassis and containers and work with outside drayage providers. This additional equipment is typically obtained from the railroad or private providers.

Non-Asset:
Non-asset intermodal providers don’t own any of their own equipment. To move their customers’ freight, they must rely on other sources for containers and chassis and work with trucking partners for drayage. Like asset-lite providers, non-asset companies get their equipment from both railroads and private providers.

While these are important distinctions to be aware of, the asset classification of an intermodal company shouldn’t be a make-or-break factor when choosing a provider. In the next section, we cover all the important points you should consider.

Here are a few suggestions to get started:

• Evaluate your current transportation strategy. Where do you see opportunities to replace another transportation mode with intermodal? Pay special attention to your OTR trucking lanes where freight is traveling 500 miles or more. These are usually ideal situations to explore intermodal as an alternative.
• Confirm opportunities that offer the greatest benefit. For every opportunity you identify, make sure it aligns with the optimal conditions for intermodal transportation. You can find these in the When to Use Intermodal section of this blog.
• Research intermodal providers. After you have identified opportunities in your supply chain, you need to research potential intermodal providers to work with. You can use our tips in the How to Choose an Intermodal Provider section to narrow down your list while researching.
• Contact the top providers on your list. Once you’ve done your research, contact the providers you are most interested in. Often, you can find a contact page on the company’s website to submit a message or a phone number to call. Once the conversation is started, you can ask any questions you have and review your intermodal strategy. If you need help identifying intermodal opportunities in your supply chain, a good provider can walk you through the process and provide their recommendations.
• Request quotes. Once you have identified the lanes you want quoted, send requests to the providers you most want to work with. Find the basic information needed for a quote here. When the quotes are returned, compare the rates against each other and your current transportation solution to ensure the switch makes sense.