Multimodal Optimization of Urban Freeway Corridors

Book excerpt: The findings of the study are two-fold: the results of what forms of multi-modal travel are used by other states and the results of the case study. Many states employ or are planning high occupancy vehicle (HOV) lanes (of all forms/types, but primarily of the concurrent flow variety) for use in urban freeway settings. High occupancy/toll (HOT) lanes were in the planning stages according to about half of the survey respondents while bus rapid transit (BRT) was being considered by two-thirds of the departments responding. Light rail transit (LRT) was only listed in 33% of the responses as being currently in use. HOT Lanes, Exclusive-Use Lanes, By-pass/Separation Lanes, Dual Facilities, and LRT had the highest number of responses for not being used as a multi-modal application within a freeway corridor. The SR 51 case study relied on existing data, modeled situations, and cost estimates to determine the most cost effective choice for multi-modal travel. Existing volume data was provided by Arizona Department of Transportation's Freeway Management System (FMS) and supplemented by a microsimulation study previously conducted for the Arizona Department of Transportation concerning the operations of the existing HOV lanes. Cost data was coalesced from literature review material and transportation data sources exclusive to Arizona. The computations factored in traffic flows under different freeway scenarios depicting different forms of multi-modal travel that would be reasonable for the SR 51 freeway. The results, ranked from most cost-effective to least cost-effective, are as follows (Note: "GP" refers to general purpose lane, and the ranges of cost values are due to different calculation methods for the projected volume by mode): (1) HOT Lane ($0.012 to $0.027 per person-mile) (2) Fourth GP Lane ($0.019 to $0.042 per person-mile) (3) HOV (w/BRT) Lane ($0.026 to $0.057 per person-mile) (existing condition) (4) Exclusive BRT Lane ($0.066 to $0.147 per person-mile) (5) Light Rail Transit ($0.161 to $0.358 per person-mile).