Diesel taxes and truck-related user fees contribute more than a third of the total revenues that are dedicated to the federal Highway Trust Fund. The Commission believes that this proportion should be at least maintained for general surface transportation investment purposes and that some increment to that funding level should be considered to pay for freight-related infrastructure. The Commission also believes that to the extent that port-related fees are used, it would be appropriate to dedicate resulting revenues to a more targeted intermodal freight investment fund. Further, the Commission suggests that the existing studies on the relative impact of freight on the highway system (i.e., cost allocation studies) be updated and critically evaluated to inform future freight-oriented taxation and user charge system decisions.
Based on the evaluation in this chapter, several possible freight-related revenue sources are worthy of consideration, but their relationship to system use and total revenue potential varies widely. In each case, administrative costs and legal issues should be weighed against revenue-raising potential. In some cases, taxes or fees would be suitable to investment in a single mode; for example, weight-distance taxes are most closely aligned with the impact of trucks on roads but are probably more expensive administratively than the current package of truck-related taxes. They also present potential compliance challenges. Other sources lend themselves to multi-modal investment, such as freight waybill taxes, but are not closely related to system use and again have administrative, implementation, and compliance weaknesses. Still other approaches, such as customs fees or container taxes, are best suited to targeted improvements at or in the vicinity of ports of entry, but they fail to reach enough of the freight highway users to be useful as a broad-based source of revenue and are particularly ill suited as means of addressing most rural freight needs.
While the Commission has attempted to provide a qualitative assessment of the alternative freight-related revenue mechanisms, further quantification and analysis, exact legal research, and political analysis are needed for policy makers to make a final determination on each mechanism's ultimate value as part of a comprehensive surface transportation funding package.
In light of the various considerations raised in this chapter, and with the possible exception of a customs duties surtax or a container tax that could be used to fund an intermodal/ border crossing program, the best way to increase funds from freight in the short term is by increasing the fees that the trucking industry currently pays into the federal Highway Trust Fund and in the medium term by moving to a vehicle miles traveled fee structure. (As noted in Chapter 6, such a system could be structured to charge by the number of miles traveled, axle weight, and specific roadway segment.)
As described in Chapter 8, this requires three actions. First, Congress should increase and, where relevant, index for inflation the current fees, including the diesel tax, truck tire taxes, and the Heavy Vehicle Use Tax paid by freight movers-with a portion of these fees being available only for freight-related investments. Second, Congress should commission a research study to assess the need for a modest shift toward freight-related users paying a higher share of total surface transportation infrastructure costs, particularly those imposed on the highway network. Finally, Congress should take steps in the near term to prepare for a transition to a VMT fee system for both trucks and passenger vehicles.