Performance Analysis of the "Zoning" Strategies for ADA Paratransit Services

ADA paratransit systems are dial-a-ride services providing public transportation to disabled customers. In large metropolitan areas, these services might adopt zoning strategies to simplify their management. The objective of this research is to provide a more in-depth evaluation and comparison between centralized and decentralized zoning strategies for the city of Houston, Texas, by developing a simulation model to evaluate the effect of zoning strategies on the productivity and service quality for the ADA paratransit service. Three decentralized zoning strategies are compared to a centralized no-zoning strategy. Results show that the decentralized "Four-zone" strategy, as opposed to the centralized no zoning strategy, needs a fleet larger by 17 percent, its empty trip miles are larger by 11 percent, values for the passenger trips per vehicle revenue hour are lower and its average waiting time is 3.7 percent lower.