This research examines a new methodology for prospectively estimating the
willingness of travelers to use a toll road by combining travel time saved with the
income of the prospective customer base. The purpose of the research is to facilitate
network level planning by allowing some reasonable predictions of acceptable toll rates
from readily available data and estimation techniques. Methods of estimating user
benefit resulted in simulated distributions of value of user time. Values of time are
linked to census tract income data for the user population to produce value of time as a
percentage of income as an indicator. As relevant literature acknowledges the tendency
toward increased toll road usage at higher income levels, it is hypothesized that linking
estimates of value of time directly to household income would produce a more useful
indicator of the travel market than do conventional indicators. Techniques for
prospectively estimating the travelshed of a toll road are compared with the actual
travelshed, as reflected in user home census tracts, as a means of evaluating the efficacy
of those techniques in estimating the market area of a prospective toll road.
Results show that considering value of time as a percentage of census tract
median income provides an improved portrayal of the toll road market, as usage of the
toll road increases with increasing income. Using census tract median income as the
income parameter has shortcomings, in that it produces anomalous results at very low
population levels. Of the two methods of estimating the travelshed, the visual estimation
approach was not satisfactory, leaving the analyst to use select link analyses instead
