At the start of 2011, we worked with Edmonton’s Disabled Adult Transit Service (DATS), a dial-a-ride service that provides year-round, door-to-door transportation to over 900,000 individuals who have significant physical and/or cognitive disabilities restricting the use of conventional modes of transportation. The success and reputation of this program has generated greater awareness of DATS, and with an estimated 18% activity limitation of the Edmonton population1, there is an expected long-term demand for this service. DATS uses a third party contractor to carry customers that they are unable to fit into their schedules. To better serve their clients, DATS needs to identify the different vehicle models and quantities of each model that would allow them to operate effectively and minimize unmet demand.
Our strategy was to evaluate demand and the performance of DATS’ current vehicle mix, taking into consideration seat-type usage, transport times and destinations, and vehicle run assignments. In our analysis of the data provided, we examined peak months, weekdays, and hours to determine how DATS treated demand. There was a prioritization for contractors to transport ambulatory clients over DATS, resulting in contractors carrying an average of 57% of total daily customers on the sample days evaluated. We found that the constraint was not the capacity of DATS’ vehicles as there were sufficient unoccupied spaces for all time windows. However, when evaluating each individual run, there exists better seat-type configurations that could recapture customers contracted out. We calculated the maximum passengers per seat-type in each vehicle run and looked at various scenarios during peak intervals where DATS had the potential to recover passengers and runs from its contractors. We evaluated and ranked different vehicle models for DATS. Based on our analysis and consideration of DATS’ needs, we recommended the purchase of two types of vehicles: the 6 wheelchair-8 flip model and the 8 passenger-4 wheelchair-2 flip model. Compared to their existing fleet mix, a test fleet ratio of 75% of the first and 25% of the second model produced preliminary results indicating DATS’ vehicles, using less runs, were able to transport more ambulatory clients and a higher number of total passengers overall.