This thesis compares actual and perceived travel times and presents a model for predicting traffic flows when there is a network disruption. The goal of this research is to demonstrate the necessity of accounting for possible differences in travel time perception and actual travel times, and also to show trends in how the route choices change based on the transformation of the perceived travel times. A pilot test was done to determine actual travel time perceptions, and the results provided the foundation for the tests presented in this thesis and the model framework. The model is separated into three phases: equilibrium assignment, link travel time transform, and logit assignment. The transform of the link travel times is best represented by an inverse cumulative Normal distribution, and the corresponding values provide quantifiable measure of the severity of a traffic network disruption. The methodology is presented and applied to two test networks to demonstrate the resulting route choice patterns. Both networks are tested for three severity levels and three levels of demand. / text