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13 methodologies incorporate the effects of intersections on av- 3. Lane additions leading up to or lane drops leading away erage pedestrian and bicycle speeds, but do not consider from intersections; other potential factors (such as interference). 4. The effects of grades between intersections; Safety and Economic Factors: Safety and economic factors 5. Any capacity constraints between intersections (such as a are not included in any of the LOS methodologies. narrow bridge); Comparable Modal LOS: The HCM uses the same service 6. Mid-block medians and two-way left-turn lanes; measure, speed, to predict traveler LOS on urban streets for 7. Turning movements that exceed 20 percent of the total auto, bicycle, and pedestrians. Transit does not use speed volume on the street; for LOS at the urban street level. However the LOS thresholds 8. Queues at one intersection backing up to and interfering for each mode were selected by committee and are not backed with the operation of an upstream intersection; and up by research indicating comparability of LOS values across 9. Cross-street congestion blocking through traffic. modes. Modal Interactions: The HCM incorporates many but not Transit TCQSM Critique all of the potential cross-modal influences on level of service. Exhibit 21 highlights the key LOS criteria for each mode. Exhibit 23 critiques the intermodal relationships in the Exhibit 22 then shows how the various modes can affect each Transit Capacity and Quality of Service Manual. of these key LOS criteria. National Multimodal Application: The TCQSM is de- The HCM takes into account the effects of pedestrians, bi- signed to be applied nationally for transit only. cycles, and transit on auto delay at signalized intersections. Level of Service from a Traveler's Perspective: The The signalized intersection delay in turn affects the estimated TCQSM LOS measures are based on surveys that identified mean speed of through traffic on the urban street. The mean service factors important to traveler perceptions. The LOS speed is the LOS criterion for an urban street in the HCM. E/F thresholds were set based on a project team/project panel Higher auto volumes indirectly affect bicycle and pedes- consensus of undesirable service from a passenger stand- trian LOS in the HCM method by affecting the signal timing point; the other thresholds ideally represent points where a at the intersections. Longer cycle lengths and longer red times noticeable change in service quality occurs (e.g., when no would increase bicycle and pedestrian delay and reduce their more seats are left), and otherwise represent even ranges of level of service on the street. the service measure between LOS A and LOS F. Higher auto volumes would indirectly affect transit relia- Applicable to Urban Streets: The TCQSM is oriented to bility by increasing the probability of congestion, but the the transit service features, not the street facility. LOS meas- HCM provides no method for estimating this effect. Thus the ures are provided for stops, routes, and the system as a whole. effect of auto volumes on transit LOS cannot currently be The measures must be adapted for use on a specific street accounted for using the available HCM procedures. facility. The effects of pedestrians on bicycle level of service and the Considers All Factors Within Right of Way: The TCQSM effects of bicycles on pedestrian level of service are accounted does not currently provide a methodology for taking into for in the analysis of off-street facilities, but not for on-street account the effects of street facility characteristics on transit facilities in the HCM. LOS. Walk and drive accessibility are currently not included Higher transit volumes, by reducing capacity and increas- in bus stop level of service. No methodology is currently ing congestion, can adversely affect bicycle and pedestrian available for estimating the effect of traffic congestion and LOS in the HCM method by affecting the cycle length and red signal operation on transit service reliability. times at signalized intersections. Safety and Economic Factors: Safety and economic factors LOS Reflects All Movements: The HCM focuses on pre- are not included in the LOS methodology. dicting urban street LOS only for the through movement for Comparable Modal LOS: The TCQSM focuses on transit. auto, bicycle, and pedestrian. The transit LOS includes any The selected service measures are specific to transit and are service on the street and at each stop. not comparable with those for other modes. Averaging LOS Across Modes: The HCM does not aver- Modal Interactions: The TCQSM incorporates many but age LOS across modes. not all of the potential cross-modal influences on level of HCM Limitations: The HCM lists nine conditions (p. 15-1) service. Exhibit 23 shows how the various modes can affect that are not accounted for in the current urban streets method- the key LOS criteria for transit. ology for auto LOS: LOS Reflects All Movements: The transit LOS includes any service on the street and at each stop. 1. Presence or lack of on-street parking; Averaging LOS Across Modes: The TCQSM does not 2. Driveway density or access control; average LOS across modes.