In recent years, costs of highway facilities have generally been considered to be the responsibility of highway users. Although the private sector has recently been called upon to assume more cost responsibility, highways are primarily financed from tax revenues and user tolls. A continuing task related to assessment of highway user fees is determination of the appropriate level of taxation for each class of highway user. Cost allocation in various forms has traditionally been a tool to achieve an equitable assignment of user responsibility. This highway cost allocation study is the sixth in a recent series begun in the early 1980s by the Transportation Cabinet and the Kentucky Transportation Center (formerly the Kentucky Transportation Research Program). Its primary objective is to determine the level of revenue contribution and cost responsibility for each class of highway user.

The base year for the study is fiscal year (FY) 1993, which is the most recent time period for which revenue and cost data are available. Highway use or travel activity is generally reported on a calendar-year basis, and 1992 has been used because it is the most recent year for which complete data are available. A basic premise of the study is that only the state-maintained system of highways should be of interest to those attempting to recoup costs (by assigning them to the appropriate highway user) expended to construct and maintain the system. In 1992, the state-maintained highway system comprised approximately 28,000 miles of the 70,000 miles of roads and streets in Kentucky while accommodating approximately 91 percent of all travel in the state. All revenue and cost data reported herein reflect estimates of monies associated with managing only the state-maintained mileage.

Highway user classes, with which revenue and cost responsibility were associated, totaled 17 and included motorcycles, cars, buses, and 14 registered or declared weight classes of trucks. Primary sources of revenue allocated to the various classes of highway users include fuel taxes, registration or license fees, usage taxes, road tolls, other motor carrier taxes, other Federal taxes, and miscellaneous taxes and fees. Primary expenditure categories include construction, maintenance and operation, administration, and enforcement. Construction expenditures were further subdivided into preliminary design and engineering, rights of way, utilities, grading and drainage, pavements and shoulders, and bridges.

Results from the analysis indicate that cost responsibility is borne most heavily by passenger cars and motorcycles (45.22 percent). Heavy trucks, those with gross weights of 62,000 pounds or more, were responsible for 26.28 percent of the cost. Pickups and other vehicles registered in the 6,000-pound category were responsible for 19.80 percent of the cost. Cost responsibility borne by all other groups totaled 8. 70 percent. Annual cost responsibilities in dollars and percentages for grouped classes of vehicles are shown in the following tabulation.

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The contents of this report reflect the views of the authors who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky or the Kentucky Transportation Cabinet. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names and trade names is for identification purposes and is not to be considered an endorsement.