NONE 20260608110845432 wseas/wseas content-registration-form+ja@crossref.org content-registration-form Engineering World 2692-5079 Uneb Gazder Department of Civil Engineering, College of Engineering University of Bahrain Sakhir 32028 BAHRAIN Transportation sector poses a major threat to the sustainable development strategies due to its diverse externalities in the form of emissions and fuel consumption heightened due to congestion, and loss of life and property due to road accidents. Roundabouts are very effective intersections in terms of efficiency and Level of Service (LOS). However, the application of roundabout has a compromise between the safety aspects of single lane roundabouts and capacity of multilane roundabouts. The aim of this research is to evaluate the impact of innovative turbo roundabout design on enhancement of the sustainability of transportation networks. To achieve this objective, three different roundabouts in Bahrain were studied and converted to turbo roundabouts based on volume distributions. Design processes were done using TORUS 5.1 and then imported to PTV VISSIM for the operational comparison with multi-lane roundabouts in terms of delays and LOS. In addition, capacities were calculated of multi-lane roundabouts based on equations in HCM 2010 (Highway Capacity Manual) and the capacities of turbo roundabout based on Gap Acceptance Model (Tanner’s Model) and the differences were shown. 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