The objective of this research is to estimate and compare the highway infrastructure cost responsibility and revenue contribution of highway users in North Carolina. The study adopted the FHWA 13 vehicle classification system and analyzed data on highway infrastructure expenditures and federal and state revenue for the years 2014-2017.
The results of this research indicate that lightweight vehicles, including motorcycles and passenger cars, contribute more to the revenue than their share of cost responsibility. Specifically, it was found that motorcycles, passenger cars, and FHWA class 3 vehicles overpay by 30%, 26%, and 8%, respectively. On the other hand, single-unit trucks with four or more axles (FHWA class 7) and all multi-unit trucks classes (FHWA classes 8-13) underpay by 37%-92% for highway infrastructure compared to the damage they cause. In summary, lightweight vehicles are currently subsidizing the cost responsibility of most trucks on North Carolina’s highway system.
The results of this study reveal that NCDOT should explore ways to increase the share of revenue contributions from trucks to improve equity in revenue generation. Several revenue scenarios were analyzed as part of this study, such as increasing the rates of current sources of revenue as well as investigating new sources, such as mileage-based user fees and dedicating state sales tax revenue to transportation. Although most of the revenue scenarios explored as part of this research are implementable and
reasonable when compared to the tax and fee structures in other states, none of these scenarios was found to lead to substantial equity improvements. Future research should focus on a detailed exploration of tax and fee structures that can significantly enhance equity in NC’s transportation infrastructure revenue generation process.
