Evaluation of travel speed of conventional buses and bus rapid transit service in Ahmedabad city, India using geo-informatics

Abstract

• GPS data logged by transit vehicles was used to determine travel speed. • Assessed spatio-temporal variability in travel speed of conventional buses and BRTS. • Identified congestion hot spots using Getis-Ord G i * statistics. • BRTS in Ahmedabad city was found 4 km/h faster than the conventional buses. • Travel Speed of BRTS declined to 13 km/h during peak-hours in inner city. Bus Rapid Transit Service (BRTS) attempts to overcome the limitations of conventional bus service with lane separation and higher operational frequency. The policy-makers are frequently required to quantitatively evaluate the improvement in quality of transportation offered by BRTS with respect to that of conventional buses to not only expand the network in newer areas within the city, but also to implement the same in other similar cities. This paper demonstrates an approach based on the Global Positioning Systems (GPS) data logged by transit vehicles in assessing the performance of conventional buses and BRTS in Ahmedabad city, India. The link travel speed derived from GPS data provides an insight into the spatio-temporal variability in conventional buses and BRTS. The congestion hot spots indicating high and low values of travel speed in conventional buses and BRTS were identified using the hot spot analysis (Getis-Ord G i * statistics). The study shows that the BRTS network did provide higher travel speed at lower variability over conventional buses in the study area. However, BRTS provided no improvement in travel speed in the densely populated inner city regions during peak hours, offering little advantage of lane separation. The study also shows the utility of voluminous GPS data logged by transit vehicles that is otherwise lying dormant with transit operators for identifying traffic hot spots within the city.