Asset Management Strategy to Meet Long-Term Transit Fleet Needs of State Departments of Transportation

State departments of transportation (DOTs) that provide the bulk of matching funds to local transit agencies for the purchase of new buses are duly concerned about the escalating costs of new buses and the lack of sufficient funds to keep up with bus replacement. An asset management strategy is presented for state DOTs to meet their long-term fleet needs. It is a two-stage process: (a) allocating capital dollars for the dual purpose of purchasing new buses and rebuilding existing buses (taking into consideration the needs of all the constituent transit agencies) and (b) distributing funds among the agencies in an equitable manner. The proposed management strategy includes two optimization models. Model 1 attempts to maximize the weighted fleet life of all the buses that are being purchased and rebuilt for a given peer group, within the constraints of a fixed budget. Model 2 is designed to maximize the remaining life of the entire peer group composed of the existing buses as well as those being replaced or rebuilt. The need for every single bus that is eligible for replacement is addressed in the model through either replacement or rebuilding. A comprehensive case study depicting a 7-year planning cycle for the entire fleet of medium-sized buses in the state of Michigan is used to demonstrate the strategy. A plan for evaluating the strategy is also presented and demonstrated. Results show that the strategy is viable and that it can be used for the designated purpose with fleet data that are currently available to the transit agencies. Even though the strategy is demonstrated with medium-sized buses, it will function efficiently with buses of different sizes and with a different number of agencies.