Alemayehu, Ambo (PhD)Meseret, Yeshitila2020-11-272023-11-112020-11-272023-11-112017-11http://etd.aau.edu.et/handle/12345678/23657Metropolitan areas have long had a history of experiencing vehicular traffic congestion particularly during peak hours for different reasons. One overlooked factor among such contributory reasons is the disorganized utilization of similar lanes by a mix of light automobiles with one or two passengers on one hand and high occupancy vehicles with well over four passengers on the other hand. High occupancy vehicles are usually public transportation motors that continuously make frequent stops to pick up and deliver passengers from/to multiple destinations along a certain corridor. Therefore, the blending of vehicles that make a non-stop through movement with such high occupancy vehicles naturally results in a poor lane utilization and reduced level of service. Addis Ababa is no stranger to this phenomenon as over one fourth of vehicular traffic on most multilane highways comprises of high occupancy vehicles. The problem is magnified as traffic management schemes that are non-infrastructural in nature are hardly exercised. This research focused on quantifying to what extent level of service on multilane highways could be improved by dedicating a single lane to high occupancy vehicles. Accordingly, a specific route was carefully chosen as a case study and the currently existing level of service was determined. In order to investigate the possible room for improvement, straight through lanes both in the middle and curb side were assigned to high occupancy vehicles one after the other and the new level of service for each lane was determined with the aid of a simulating software. Results indicated that dedicating outer through lanes to high occupancy vehicles on the chosen case study can result in better lane utilization and improved level of service from D to C as evident from the registered shorter travel time as well as increased average speed.en-USHOV lanetraffic managementtraffic flowperformance evaluationsimulationThesis