Oregon Highway Cost Allocation Study

At a Glance



Oregon Department of Administrative Services

Related Projects

For each legislative session since 2001, ECONorthwest has conducted the Oregon Highway Cost Allocation Study (HCAS) of the Oregon Office of Economic Analysis. The study determines whether light and heavy vehicles are paying their fair shares of highway user fees, as required by the Oregon Constitution. A Study Review Team, consisting of academic experts and interested parties, oversees the project. Each study includes several issue papers on topics relevant to highway costs and funding. ECONorthwest developed and refined the model, which allocates budgeted expenditures in the upcoming biennium, in dozens of categories, to vehicles by 2,000-pound weight class. It also attributes forecasted revenues to the same vehicle classes and compares each class’s share of revenues to its share of allocated expenditures. The study’s findings are presented to legislative committees during the legislative session.

ECONorthwest also conducted an additional study in which shares of costs were determined by the shares of fees that would be paid by each vehicle class under an efficient pricing scheme. In an efficient pricing scheme, variable fees are calculated based on the wear and tear a vehicle imposes on roads and bridges given its weight, configuration, and characteristics of the road, on the congestion costs it imposes on other users given the time and place it is traveling, the emissions it produces, and its share of administrative costs not funded through other sources.

ECONorthwest recently completed the 2023 HCAS.

Completed Tasks:

  • Built a new highway cost allocation model and applied it to the 2023-25 biennium.
  • Modified the national NAPHCAS (NAPCOM for HCAS) model to better work with Oregon-specific data and to better integrate with the Oregon model.
  • Model enhancements to increase the transparency of data pre-processing and improved user features. Comprehensive technical documentation and a user guide were developed for the enhanced HCAS model.
  • Model enhancements incorporate weigh-in-motion data and adaptation to the new National Pavement Cost Model. Comprehensive technical documentation and user guide were updated for the enhanced HCAS model.

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Oregon Highway Cost Allocation Study