Modeling Bus Lane Priorities in a Motorcycle Environment Using SATURN

Bus lanes and median bus ways such as those in Curitiba, Brazil, and Bogotá, Colombia, are attracting a great deal of attention worldwide. For many Asian developing cities, there is an interest in how successfully bus lanes and bus rapid transit will function, given that traffic conditions in such cities typically are different from those found in Latin America. This paper addresses this issue for Asian cities whose traffic is dominated by motorcycles, concentrating particularly on Hanoi, Vietnam. With the use of a SATURN mesoscopic simulation model for Hanoi (with 322 junctions and 1,108 links), different bus lane–bus way designs are compared in regard to their effects on travel time savings. Results show that the level of motorcycle violations has an important impact on the success of bus lane schemes and that there is no significant speed improvement on bus lanes if enforcement is weak. Bus ways can achieve much higher bus speeds than can bus lanes, but general traffic speeds are likely to reduce them significantly if there is no mode switching from private modes to buses. In such circumstances the potential extra delay due to a poorly designed bus way is greater than that due to a poorly designed bus lane. The route-switching flexibility of motorcycles also has considerable effects on the performance of bus lanes and bus ways.