Analisis Efektivitas Pembangunan Overpass Jalan Stasiun Medan Dalam Mengurangi Kemacetan Lalu Lintas Di Kawasan Inti Kota

Abstract

This study aims to analyze the effectiveness of the Stasiun Medan Overpass construction in reducing traffic congestion and improving traffic performance in Medan’s city center. The research employed a quasi-experimental design with a Before–After Analysis model combined with the Difference-in-Differences (DiD) approach to measure changes in key traffic performance indicators before and after the overpass construction. The data used in this study consist of primary data from direct traffic observations and user perception surveys, as well as secondary data obtained from the Medan Transportation Agency and the Central Bureau of Statistics. The results indicate that the overpass construction significantly improved traffic performance. The degree of saturation (DS) decreased from an average of 0.91 to 0.71, while the average vehicle speed increased by 7–10 km/h after the overpass became fully operational. The simple linear regression model produced the equation Ŷ = 0.998 − 0.007X with R² = 0.79, meaning that approximately 79% of the variation in DS is explained by changes in vehicle speed. The Difference-in-Differences test also confirmed that the overpass intervention significantly reduced congestion levels in the city center. From a social perspective, a survey of 120 respondents revealed that user perceptions of traffic smoothness, travel time efficiency, safety, and drop-off zone orderliness were rated high, with average scores above 4 on a 1–5 Likert scale. These findings align with the Level of Service concept (TRB, 2010), which emphasizes the balance between technical performance and user satisfaction. Therefore, the Stasiun Medan Overpass has proven effective both technically and socially, serving as an example of data-driven and user-oriented urban transportation planning aimed at improving infrastructure service quality.