Kinerja Simpang Tak Bersinyal: Studi Kasus Jalan Wates KM 5 (Barat Pasar Gamping)

Abstract

Sleman Regency has a high population density, requiring adequate transportation facilities to prevent traffic congestion and excessive fuel consumption. One of the intersections that frequently experiences long vehicle queues during peak hours is located at Jl. Wates Km 5, west of Gamping Market. This study aims to evaluate the performance of the intersection and propose appropriate improvement measures. The research method refers to the Indonesian Highway Capacity Manual (MKJI) 1997. Primary data were collected through field surveys conducted over three days (Monday, Wednesday, and Saturday) during morning, midday, and evening peak hours, while secondary data on population were obtained from relevant government agencies. The analysis of the existing condition indicates a degree of saturation (DS) of 1.249, which exceeds the recommended limit specified in MKJI 1997 (DS < 0.80). To address this problem, two improvement alternatives were evaluated. The first alternative involved installing a median barrier and reducing roadside friction from a medium to a very low level, resulting in a reduction of the DS to 0.921. The second alternative combined the first measure with a 2.5-meter widening of the minor-road approach, further reducing the DS to 0.894 and decreasing the average intersection delay to 15.236 seconds. Although the final degree of saturation remains above the ideal threshold of 0.80, both alternatives significantly improve traffic flow by reducing congestion and vehicle delay at the intersection.