Performance Evaluation of Signalized Intersection- A Case study of Prithivi Chowk, Pokhara

Abstract

Prithivi Chowk, a heavily trafficked signalized intersection in Pokhara, Nepal, currently relies on manual traffic control, leading to significant issues during peak hours. This study employs the Highway Capacity Manual (HCM) methodology to evaluate the intersection's performance, aiming to address congestion and recommend improvements. Data collected from July 10-12, 2023, during peak hours, indicated traffic volumes of 6369.5 PCU/h in the morning and 6275.5 PCU/h in the evening, demonstrating over-saturation. The analysis included 12 vehicular and 4 pedestrian directions, with peak hour factors of 0.942 and 0.954, respectively.Initial assessments of three lane configurations and signal phasing plans revealed all phase plans exceeded capacity, resulting in a Level of Service (LOS) 'F'. Subsequent evaluations involved geometric enhancements, such as adding lanes. Increasing lanes in the Eastbound Through, Northbound Right Turn, and Westbound Right Turn directions significantly improved performance, achieving LOS 'D' in the third iteration of Phase Plan I. Optimal signal timings were designed using the Webster method, resulting in cycle lengths of 123 seconds for the morning peak and 116 seconds for the evening peak. The study highlights critical challenges and proposes targeted measures to enhance traffic flow at Prithivi Chowk, offering valuable contributions to transportation engineering and urban planning in Nepal. These findings emphasize the need for systematic traffic management improvements to mitigate congestion and enhance intersection performance.