Toward Sustainable Transit Operations and Performance Enhancement Using Archived Automatic Vehicle Location Data
Portland, Oregon's transit agency, TriMet, provided a year's worth of archived stop-level Bus Dispatch System (BDS) AVL data for a model that optimizes the rider vs. access costs for each passenger. This study was conducted along TriMet's Route 19, which is a 7.7 mile bus route that had 46 scheduled stops. The average stop spacing along this route was approximately 900 ft, with 18 minute headways and an AM peak mean passenger load of 37 passengers.
Based on the optimization model, the authors concluded that by spacing the stops between 1,300 and 1,400 ft apart, TriMet's Route 19 could save over 5 minutes per trip after eliminating or consolidating 14 scheduled bus stops. The time savings are generated from the reduction in acceleration/deceleration time needed when leaving or entering a stop. In the long run, this would save over 1,500 hours of operation each year, resulting in nearly $100,000 in cost savings on a single route. By reducing trip times, TriMet could add twelve more trips per day on Route 19 and reduce mean headways to 15 minutes with the same fleet size.