The lesson from the 2019 Infrastructure Week is that throwing money at the problem is not enough. Panel discussions, speeches, and presentations this week did not dwell on the proposed multi trillion dollar funding amount but focused rightly on what the goals and objectives of a federal investment program should be. The major theme of the week has been creating a cohesive vision to help justify the need and target funding to the most worthwhile projects.

When Americans imagine investing in transportation infrastructure, they mostly think of fixing potholes, improving old bridges, and unsnarling bottlenecks on the roads they use to commute and conduct their daily lives. But the freight network is not as often part of the infrastructure discussion. Simple analysis show that serious investment in freight, particularly for the freight that does not travel on highways, could accomplish several national goals and could be the basis for a substantial and responsible investment program.

Trucks carry the vast majority of freight by value, and the largest proportion of freight measured by ton-miles (Table 1). A significant amount of freight is also moved by air and through movements on multiple modes, but most freight starts and ends with a single freight mode. It is often siloed with high value goods traveling by truck, and lower value goods like grain and coal, traveling by rail and barge. Trucking is an immensely valuable part of the national economy, but in many cases there is no other option for shippers and the network has become overly reliant on the least efficient mode.

Table 1: Freight movement in the United States, select modes

Source: Freight Facts and Figures 2017, Bureau of Transportation Statistics

Shifting a small portion of the overall truck freight could have several benefits to the transportation network. Trucking accounts for nearly 7 percent of all US greenhouse gas emissions, and rail and waterway shipping are vastly more efficient. A standard semi truck, on average, can move a ton of freight about 145 miles for each gallon of diesel fuel (standard trucks can carry up to 40 tons of freight in a load, and many carry less than that). The railroad network can take that same ton 477 miles per gallon per ton, with a single rail car carrying 100 tons of freight. And the inland barge system averages 647 miles per gallon per ton, which can carry dozens of shipping containers weighing hundreds of tons. Moving a modest 10 percent of the truck traffic on to barges and trains could save more than 10 million tons of carbon emissions annually, equivalent to cutting about 0.15 percent from total US emissions.

Further, trucks cause a disproportional amount of wear and tear on roadways and also create significant congestion. Around 10 percent of the vehicles on the Interstate Highway System are trucks, which take up significant roadway space and need more time to accelerate in traffic. Due to their disproportionate burden on roadway life, highway engineers ignore other vehicles and only account for trucking when determining the life of pavement. Declines in truck traffic can lengthen roadway life, improve traffic flow, and improve safety.

Freight rail and inland waterways need not only transport low value, bulk goods. Freight railroads have long carried high value goods, recently adding capacity to move more intermodal containers. Inland waterways in Europe, particularly the Rhine River, carry barges packed with shipping containers full of high value goods. Major transportation waterways like the Ohio River, the Illinois River, and the Mississippi River cut through the industrial heartland, connecting manufacturing centers throughout the country that could benefit from low cost, efficient transportation options.

Of course, shippers will move their goods on the system that drives the most value, and diversion requires service that is competitive with trucking. This requires significant upfront investment in modernizing the entire inland waterway network. The freight railroads have done a remarkable job on the infrastructure within their network, but federal investment could encourage the revival or improvement of branch lines and intermodal connectors that facilitate access to and from shipment centers.

But investment in waterways and freight rail are not comparable to the funding given to highway networks. The federal-aid highway network, the backbone of the trucking network, receives more than $40 billion in federal investment annually. Meanwhile, the inland waterways and portions of the freight rail system have fallen into disrepair. The 25,000 miles of inland waterways that connect economic centers on the Mississippi River system, the Great Lakes, and other parts of the country receive about $110 million annually from the federal government. More than half of the 239 locks are beyond their 50 year life span, and the average delay per lock is now over two hours. The decline in reliability accounts for some of the drop in traffic: the system lost a staggering 46 percent of its ton-miles between 1988 and 2016.

The freight rail system is owned and operated by the private sector and is in much better shape, particularly on the busiest corridors which are more economically lucrative. However, railroads continue to shed unprofitable lines, either by abandoning service or selling them to smaller railroads. Today, the route mileage of US railroads is less than half of what it was in the 1970s. While some of those lines were redundant, shippers that connected to them lost a viable and inexpensive alternative. While shipments for intermodal and other high value goods have been increasing, boxcar and other non-bulk carload categories have declined. The federal government provides limited eligibility in a few of its small discretionary investment grant programs for freight rail and intermodal connectors.

Trucking is and always will be an important aspect of the freight network, and the system that supports it deserves continued and smart investment. But putting federal infrastructure investment toward inland waterway and rail freight, perhaps coupled with regulatory reforms, could make alternatives to trucking more competitive. Increasing water and rail modal share diversifies this overly singular sector, enabling a safer, more resilient, and more efficient transportation system for the country.

Chris Oster, O’Bryant Fellow at the Eno Center for Transportation, contributed to this article.

The views expressed above are those of the author and do not necessarily reflect the views of the Eno Center for Transportation.