Crunkleton, JoshuaRoad users fail to realize their role in congestion. This thesis aims to calculate the appropriate charges required for users of I-495 - the Capital Beltway surrounding Washington, D.C. - in order to fulfill their portion of congestion costs. By developing a model from existing data that showcases traffic characteristics causing congestion, the user charges necessary to cause drivers to realize the congestion costs that their vehicles impose on the rest of the traffic stream are determined. This study concludes that under typical traffic flow conditions for the Capital Beltway, charges ranging from $0.03 to $0.08 per passenger car equivalent (PCE) per mile during AM and PM peak periods cause drivers to realize their contribution to congestion costs. These results are lower than the $0.08 to $0.50 per-mile charges that previous research has estimated. As vehicles occupy various amounts of road space, charges on a PCE basis are most equitable.en-USThesisTransportationEngineering, Civil