This synthesis report will be of interest to transportation agency planners; design, construction, and maintenance engineers; and administrators, managers, economists, and other decisionmakers involved in programming highway pavement projects. This synthesis describes current practice with regard to road user and mitigation costs in highway pavement projects. Information for the synthesis was collected by surveying U.S. and Canadian transportation agencies and by conducting a literature search of both domestic and foreign publications. This report of the Transportation Research Board provides detailed information on the various methods employed by transportation agencies to estimate user costs. The advantages and disadvantages of each are reported. Information on the various components of user costs (that is, time related, vehicle operating, safety, and environmental costs) is also included. In addition, the study reports on the various mitigation strategies available to agencies to reduce user costs. Information is also provided on how user costs and mitigation strategies have been applied to evaluate different alternatives; and how uncertainties, political considerations, and quality control contribute to the decisionmaking process.

"This [i.e. The] purpose of this guidebook is to help organizations improve the development, implementation, and management of their transportation plans and programs. By adding an element of performance measurement and monitoring to existing transportation planning processes, agencies can obtain better information about the performance of their existing programs and services. Performance-based planning provides a process and tools to identify and assess alternative programs, projects, and services with respect to overall transportation plan goals and objectives."--Ch. 1. Overview, p. 3.

Federal and state governments have played a vital role in the nation economy by facilitating the movement of people and goods through significant investments in highways. At the federal level, the Department of Transportation (DOT) Federal Highway Administration (FHWA) uses a computer model known as the Highway Economic Requirements System (HERS) to estimate the future investment required to maintain and improve the nation highways. DOT reports the results of this analysis to the Congress on a biennial basis. However, state governments make a large number of highway infrastructure investment decisions. States currently use a variety of analytic tools to make these decisions. Interest in using HERS at the state level has grown. Two states Indiana and Oregon are already using customized versions of the model, and in December 2000, FHWA began a pilot project to test its state-level version of HERS, called HERS-ST, with interested states.