I-66 Multimodal Study Final Report - Virginia Department of ...

Multimodal PackagesTransit Accessibility – Transit accessibility was measured as the number of households andjobs with access to bus service in the study area. Given the high level of transit service inthe study area this measure did not change very much between alternatives.Nonmotorized Travel – Nonmotorized travel was measured by looking at the number ofnonmotorized trips generated by the model for the defined study area. This measureincluded walk access transit trips for both the production end and the attraction end in thedefined study area.Level of Service MappingFor each multimodal package, level of service (LOS) maps were generated to illustrate the effectof the transportation improvements within each package on network and modal performance.LOS maps were produced for the highway facilities, arterials, transit service, and bicycle facilities(on- and off-road) in the study area. An overview of the methodologies used for producingthe LOS maps and transit evaluations are detailed below.Freeway FacilitiesFor I-66, the LOS was calculated using procedures outlined in the 2000 Highway CapacityManual (HCM). This included mainline segments, weave segments, and merge and divergesegments. The traffic volume output from the travel demand forecast model was postprocessedbased on the procedures outlined in National Cooperative Highway ResearchProgram (NCHRP) Technical Report 255 “Highway Traffic Data for Urbanized Area ProjectPlanning and Design.” Freeway LOS maps were generated representing the followingscenarios: Eastbound and westbound peak hour (morning and evening) existing conditions; Eastbound and westbound peak hour (morning and evening) CLRP+ Baseline; and Eastbound and westbound peak hour (morning and evening) for Package 1 through 4.For all freeway LOS maps, I-66 conditions are displayed for eastbound and westbound togetheron each map.Arterial RoadwaysArterial level of service was calculated based on the volume to capacity ratio calculated by theregional travel demand forecasting model on four major east/west arterial corridors in thestudy area. The volume to capacity ratios were then equated to a specific LOS based on criteriaoutline in the 1985 HCM. Arterial LOS maps were generated representing the followingscenarios: Eastbound and westbound peak hour (morning and evening) existing conditions; Eastbound and westbound peak hour (morning and evening) CLRP+ Baseline; and Eastbound and westbound peak hour (morning and evening) for Package 1 through 4.3-8 I-66 Multimodal Study