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92 CHAPTER 9 Integrated Multimodal LOS Model Framework This section provides an overview of the proposed urban people can actually distinguish only two to three levels of street LOS framework and the proposed LOS modeling service. However, public agency planners and engineers need system. to be able to predict how close a facility is to an unacceptable level of service. So the six levels have been retained for agency planning purposes, rather than because people actually can 9.1 The Framework distinguish among them. The proposed multimodal LOS framework for urban Level of service is defined for each mode as shown in streets reports a single average level of service for each of four Exhibit 98. modal users of the urban street: 9.2 The Integrated LOS 1. Auto drivers, Modeling System 2. Bus passengers, 3. Bicycle riders, and The proposed LOS modeling system relies on 37 variables 4. Pedestrians. to predict the perceived degree of satisfaction experienced by travelers on the urban street. These variables consist of The individual modal levels of service are NOT combined four basic types: facility design, facility control, transit ser- into a single comprehensive level of service for the facility be- vice characteristics, and the volume of vehicle traffic on the cause this would disguise the disparities in the perceptions of facility. quality of service for the four modes. The urban street LOS for a given mode is defined as the Input Variable Interactions Among Modes average degree of satisfaction with the urban street that would be reported by a large group of travelers using that mode of Exhibit 99 lists the input variables and their major interac- travel if they had traveled the full length of the study section tions. Minor interactions are not shown in this exhibit, but of the street. The video lab research showed that the degree of are discussed below. satisfaction experienced by an individual traveler for a given The Auto LOS Model 1 uses two variables: Auto Stops Per situation varies widely across individuals. Consequently, this Mile, and Presence of Left-Turn Lanes. framework focuses on predicting the average degree of satis- faction of a large group of people exposed to the same urban The presence of a left-turn lane is a facility design feature. street experience. Due to fatigue effects, travelers actually The stops per mile are directly influenced by the intersec- traveling the full length of the facility would forget key aspects tion control type and the settings of the traffic signal. High of their experience and report a different level of service than auto and transit volumes can increase the probability of would several travelers traveling short lengths of the facility. stopping. Pedestrian and bicycle volumes at intersections This framework takes the LOS perceptions of travelers on reduce the saturation flow rate, which reduces speed and short sections of urban street and compiles them into an es- increases stops. timate of LOS for the full length of the street. The six-letter grade A-F LOS structure of the HCM has The Auto LOS Model 2 uses two variables: Percent of been preserved. Many of the statistical results suggest that Posted Speed Limit, and Median Type.

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93 Exhibit 98. Definition of LOS by Mode. Level of Auto Transit Bicycle Pedestrian Service A Best Performance Very Satisfied Best Performance Best Performance B C D E F Worst Performance Very Dissatisfied Worst Performance Worst Performance Exhibit 99. Interaction of Modal LOS Model Inputs. Inputs to LOS Models Facility Facility Transit Auto Transit Bicycle Pedestrian Design Control Service Volume Volume Volume Volume Auto LOS Model #1 Auto Stops (or Delay) XXX XXX XXX XXX XXX Left Turn Lanes XXX Auto LOS Model #2 Mean Speed XXX XXX XXX XXX XXX Median Type XXX Transit LOS Model Pedestrian LOS XXX XXX XXX XXX XXX Bus Headway XXX Bus Speed XXX XXX XXX XXX XXX Bus Schedule Adherence XXX XXX XXX XXX XXX Passenger Load XXX Bus Stop Amenities XXX Bicycle LOS Models Bike-Pedestrian Conflicts* XXX XXX XXX Driveway Conflicts/Mile XXX Vehicles Per Hour XXX XXX Vehicle Through Lanes XXX Auto Speed XXX XXX XXX XXX Percent Heavy Vehicles XXX XXX Pavement Condition XXX XXX XXX Width of Outside Lane XXX On-Street Parking Occupancy XXX XXX Cross Street Width XXX Pedestrian LOS Models Pedestrian Density XXX XXX Pedestrian-Bike Conflicts* XXX XXX XXX Width of Shoulder XXX Width of Outside Lane XXX On-Street Parking Occupancy XXX Presence of Trees XXX Sidewalk Width XXX Distance To Travel Lane XXX Vehicles Per Hour XXX XXX Vehicle Through Lanes XXX Average Vehicle Speed XXX XXX XXX XXX XXX XXX Right Turns On Red XXX XXX XXX XXX Cross Street Speed XXX XXX Cross Street Vehicles/Hour XXX XXX Cross Street Lanes XXX Crossing Delay XXX Right-Turn Channelization XXX Block Length XXX Signal Cycle Length XXX XXX XXX XXX Signal Green Time XXX XXX XXX XXX "XXX" indicates that input variable is influenced by that factor. * Ped/bike conflicts come into play only for paths outside of roadway but within right-of-way of street.

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94 The Median Type is a facility design feature. On-Street Parking Occupancy is determined by the park- The percent of posted speed limit that traffic is able to travel ing controls, available off-street parking, and the density of the full length of the street is directly influenced by the in- land uses in the area. Facility design determines whether a tersection control type and the settings of the traffic signal. parking lane is provided and whether or not parking is pro- High auto and transit volumes can reduce the mean speed. hibited during peak hours. Pedestrian and bicycle volumes at intersections reduce the Cross Street Width is determined by the facility design. saturation flow rate, which reduces mean auto speed. The Pedestrian LOS Model uses the following variables: The Transit LOS Model uses 6 variables: Pedestrian LOS, Pedestrian Density, Bicycle-Pedestrian Conflicts (if facility is Bus Headway, Bus Speed, Bus On-Time Performance, Pas- shared), Width of Shoulder, Width of Outside Lane, On- senger Load, and Bus Stop Amenities. Street Parking Occupancy, Presence of Trees, Sidewalk Width, Distance To Travel Lane, Vehicles Per Hour, Vehicle The pedestrian LOS is determined by the facility design, in- Through Lanes, Average Vehicle Speed, Right-Turns on Red, tersection controls, the volume of auto and transit traffic, Cross Street Speed, Cross Street Vehicles/Hour, Cross Street and the pedestrian volume (pedestrian volumes influence Lanes, Crossing Delay, Right-Turn Channelization, Block signal timing, which affects signal delay for pedestrians, Length, Signal Cycle Length, Signal Green Time which affects pedestrian LOS). The bus headway is determined by the transit service Pedestrian Density (Computed according to HCM). provider, which is related to the passenger loads. Bicycle-Pedestrian Conflicts (only if bicycles share the Bus speed is determined by the facility controls (signal set- pedestrian facility). tings), the amount of auto and transit traffic, and the num- Width of Shoulder is a design feature. ber of boarding passengers at each stop. Bicycles in the Width of Outside Lane is a design feature travel lanes may delay buses. Heavy pedestrian volumes at On-Street Parking Occupancy is determined by the park- intersections (or mid-block) may delay buses. ing controls, available off-street parking, and the density of Bus on-time performance is determined by the service land uses in the area. Facility design determines whether a provider (e.g., number of back up buses, and maintenance parking lane is provided and whether or not parking is pro- to prevent breakdowns). It is also influenced by the auto, hibited during peak hours. bicycle, and pedestrian volumes on the street. Presence of Trees is a design feature. Passenger load is determined by the density of development Sidewalk Width is a design feature. in the area, the relative convenience of other modes of travel, Distance to Travel Lane is a design feature. and the bus headways provided by the transit operator. Vehicles Per Hour is determined by the auto, truck, and Bus stop amenities are a design feature of the facility. transit volumes. Vehicle Through Lanes is a design feature of the facility. The Bicycle LOS Model uses the following variables: Drive- Average Vehicle Speed is determined by the facility design, way Conflicts/Mile, Vehicles Per Hour, Vehicle Through the facility control (speed limit), and the auto, bus, bicycle, Lanes, Speed Limit, Percent Heavy Vehicles, Pavement and pedestrian volumes on the facility, to the extent that Condition, Width of Outside Lane, On-Street Parking Occu- bicycles and pedestrians share (or cross) the traveled way pancy, and Cross Street Width. used by motor vehicles. Right-Turns on Red are determined by the facility control Bicycle-Pedestrian Conflicts (only if bicycles share the (are they allowed?). They are influenced by the auto and pedestrian facility). transit volumes. Heavy pedestrian volumes may reduce the Driveway Conflicts/Mile are a design feature. ability of autos or buses to turn right on red. Vehicles Per Hour is determined by the auto, truck, and Cross Street Speed is determined by the design and control transit volumes. of the cross street. It is influenced by cross-street volumes. Vehicle Through Lanes is a design feature of the facility. Heavy pedestrian or bicycle volumes may reduce the cross Speed Limit is a control feature of the facility. It is influ- street speed. enced by the facility design. Cross Street Vehicles/Hour is determined by the auto and Percent Heavy Vehicles is influenced by the auto, truck, transit volume. and transit volumes. Cross Street Lanes is a design feature. It is influenced by the Pavement Condition is a facility maintenance feature. It is auto and transit volumes. influenced by auto, truck, and transit volumes and the Crossing Delay is determined by the intersection control pavement design. (signal timing), which in turn is influenced by auto, bus, Width Of Outside Lane is a design feature. and pedestrian volumes.