Cover Image

Not for Sale



View/Hide Left Panel
Click for next page ( 7


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 6
6 Exhibit 1. Contacts for State of Practice Survey. Contact Agency Location Geographic US Agency Type 1. Conan Cheung MTDB San Diego, CA West Transit Operator 2. Douglas Dalton Wisconsin DOT Milwaukee, WI Central DOT 3. Doug McLeod Florida DOT Tallahassee, FL East DOT 4. Juan Robles Colorado DOT Denver, CO Mountain DOT 5. James Okazaki Los Angeles DOT Los Angeles, CA West City 6. Carolyn Gonot Santa Clara VTA San Jose, CA West CMA/Transit 7. Jim Altenstadter PIMA AG Tucson, AZ Mountain MPO 8. John Halkias FHWA Washington, DC East Federal Bicycle LOS For shared bicycle and pedestrian paths, the pedestrian LOS is computed according to the expected number of Chapter 19 of the HCM provides bicycle LOS criteria, bicycle-pedestrian encounters per hour (see Exhibit 6). The thresholds, and estimation procedures for off-street paths criteria and thresholds are based on research by Botma [7]. and designated bicycle lanes on urban streets (summarized in A procedure is provided for estimating this based on pedes- Exhibit 3 and 4). It is based on research conducted for the trian and bicycle volumes. FHWA [4]. At signalized intersections, the pedestrian LOS is measured The HCM provides procedures for estimating mean bicy- using average delay to the pedestrians waiting to cross the cle speed and mean control delay. The mean control delay is streets (see Exhibit 7). A procedure is provided for estimating estimated based on the signal timing at each signal. The mean delay based on the pedestrian or vehicle signal timing. speed is estimated by reducing the presumed 15 mph bicycle Average crossing delay is also used to estimate pedestrian free-flow speed by the delay at each signal. LOS for unsignalized intersections. The LOS thresholds are For off-street bicycle/pedestrian paths, the HCM-adopted more conservative (less than 5 seconds of delay equals LOS A. bicycle LOS criterion is based on the frequency of encounters More than 45 seconds of delay equals LOS F). (i.e. passing and meeting events) between bicyclists and For urban streets with sidewalks, the HCM bases the pedestrians on the path. For two-way, two-lane paths, less pedestrian level of service on mean speed over the length of than 40 encounters per hour is LOS A. More than 195 the street (see Exhibit 8). The average walking speed between encounters per hour is LOS F. A procedure is provided for intersections is reduced according to the average wait time at estimating the number of encounters based on pedestrian each intersection to arrive at a mean walking speed for the and bicycle volumes. length of the urban street. Pedestrian LOS Transit Capacity and Quality of Service Manual Chapter 18 of the HCM provides pedestrian LOS criteria, thresholds, and estimation procedures for sidewalks, street TCRP Report 100: Transit Capacity and Quality of Service corners, crosswalks, and off-street paths. It is based on Manual, 2nd Edition (TCQSM) presents a two-dimensional research conducted for the FHWA [5]. LOS framework. It is a matrix covering two service quality For sidewalks, the key service criterion is space per pedes- dimensions (i.e., Availability and Comfort & Convenience) trian (inverse of density) (see Exhibit 5). A procedure is pro- for three transit system elements (i.e., Stops, Route Segments, vided for estimating this based on facility width and pedestrian and Systems) (see Exhibit 9). Each of the six cells of the ma- volumes. These are based on observations from Fruin [6]. trix provides a service measure for which levels of service are Exhibit 2. Urban Street Level of Service. Urban Street Class I II III IV Range of FFS 45-55 mph 35-45 mph 30-35 mph 25-35 mph Typical FFS 50 mph 40 mph 35 mph 30 mph LOS A >42 mph > 35 mph >30 mph >25 mph B >34-42 >28-35 >24-30 >19-25 C >27-34 >22-28 >18-24 >13-19 D >21-27 >17-22 >14-18 >9-13 E >16-21 >13-17 >10-14 >7-9 F 16 13 10 7 FFS = mid-block free-flow speed of street. Exhibit adapted from Exhibit 15-2, Highway Capacity Manual

OCR for page 6
7 Exhibit 3. HCM Bicycle LOS Exhibit 6. HCM Pedestrian LOS for Bicycle Lanes on Urban Streets. Criteria for Paths. LOS Average Bicycle Speed LOS Encounters/hour A > 14 mph A 38 B >9-14 B >38-60 C >7-9 C >60-103 D >5-7 D >103-144 E 4-5 E >144-180 F 180 Adapted from Exhibit 19-5 of the Highway Capacity Adapted from Exhibit 18-8 of the Highway Capacity Manual. Manual Exhibit 4. HCM Bicycle LOS Exhibit 7. HCM Pedestrian LOS at Signals. at Signals. LOS Average Control Delay LOS Average Crossing Delay A < 10 secs A < 10 secs B 10-20 B 10-20 C >20-30 C >20-30 D >30-40 D >30-40 E >40-60 E >40-60 F >60 F >60 Adapted from Exhibit 19-4 of the Highway Adapted from Exhibit 18-9 of the Highway Capacity Capacity Manual. Manual. Exhibit 5. HCM Pedestrian Exhibit 8. HCM Pedestrian LOS LOS Criteria for Sidewalks. for Urban Streets. LOS Space/Pedestrian LOS Mean Walking Speed A >60 S.F. A > 4.36 fps B >40-60 B >3.84-4.36 C >24-40 C >3.28-3.84 D >15-24 D >2.72-3.28 E >8-15 E >1.90-2.72 F 8 F < 1.90 fps S.F. = square feet. Adapted from fps = feet per second. Adapted from Exhibit 18-14 Exhibit 18-3 of the Highway Capacity of the Highway Capacity Manual. Manual developed; the TCQSM 1st Edition (TCRP Web-Only Docu- For transit route segments and corridors, the hours of ser- ment 6) also provided one or more other performance meas- vice each day (i.e., the number of hours per day when service ures also thought to be important to consider. Lower-level is available at least hourly) is the LOS criterion (see Exhibit measures (e.g., stop level) are also applicable at higher levels 11). For route segments and corridors where stops are made, (i.e., the route segment or system levels). service frequency would also be evaluated at the individual The TCQSM distinguishes between demand-responsive stops (depending on routing and scheduling patterns, not all transit and fixed-route transit service. The LOS criteria for buses may stop at every stop). fixed-route transit service are covered in this review. At the system level, the service coverage area as a per- centage of the transit supportive area is the LOS criterion. The transit supportive area is defined as the area with a Availability Measures of Level of Service minimum density of four jobs per gross acre or three For transit stops the frequency of service is the LOS crite- dwellings per gross acre, based on work by Pushkarev and rion (see Exhibit 10). Zupan [8]. The transit service coverage area is that area Exhibit 9. TCQSM Two-Dimensional LOS Framework. LOS Dimension Transit Stop Route Segment System Availability Frequency Hours of Service Coverage Comfort & Convenience Load Factor Reliability Time Differences Adapted from Exhibit 3-1, Transit Capacity and Quality of Service Manual

OCR for page 6
8 Exhibit 10. TCQSM Service The on-time performance measure applies to all services Frequency LOS. with a published timetable, and its LOS thresholds are all in 5% increments, with the LOS E/F threshold set at 75%. The LOS Vehicles Per Hour A >6 headway adherence measure now applies to all services B 5 to 6 scheduled to a headway or operating at headways of 10 min- C 3 to 4 utes or less (thus, both measures could apply to some routes). D 2 E 1 The measure definition allows for variable headways during F <1 the peak hour, and the LOS thresholds correspond to the Adapted from Exhibit 27-1 of the probability that no more than a certain percentage of transit Highway Capacity Manual. vehicles would be more than one-half headway off schedule. For the system level, the LOS criterion is door-to-door Exhibit 11. TCQSM Hours "travel time difference" between driving a car and taking of Service LOS. transit. If transit takes 60 minutes longer than driving, it is LOS Hours Per Day LOS F for transit. If they are equal, or transit is faster, it is LOS A 19-24 A for transit. B 17-18 In addition to the LOS measures presented in the Quality C 14-16 D 12-13 of Service section of the TCQSM, the Stop, Station, and Ter- E 4-11 minal Capacity section presents a series of pedestrian levels of F 0-3 service for elements of passenger facilities, such as walkways Adapted from Exhibit 27-4 of the and stairways, based on work by Fruin (same reference as pre- Highway Capacity Manual. vious). These levels of service are presented more for design purposes (e.g., sizing a station element to provide a certain within the transit supportive area that lies within one- level of service) than for evaluating existing facilities. These quarter air mile of a stop. Greater than 90% is LOS A. Less levels of service are similar to, but have different thresholds than 50% is LOS F. Exhibit 13. TCQSM Reliability LOS for Infrequent Urban Scheduled Comfort & Convenience Measures of LOS Transit Service. For transit stops, the TCQSM "comfort and convenience" LOS On-Time Percentage measure of level of service is based on passenger load (see A 95.0-100.0% Exhibit 12). For typical bus services operating on urban B 90.0-94.9% streets, where most passengers would be seated, LOS A-C is C 85.0-89.9% D 80.0-84.9% based on the load factor (i.e., total number of passengers E 75.0-79.9% divided by the number of seats), while LOS D-F is based on F <75% the average area per person available for standees. This meas- Applies to scheduled service of fewer than six ure originated in the 1985 HCM. vehicles per hour. Adapted from Exhibit 3-29 of the TCQSM. For route segments and corridors, the comfort and con- venience level of service measure is "on-time performance" Exhibit 14. TCQSM Reliability LOS and headway adherence. For scheduled service of fewer than for Frequent Urban Scheduled six vehicles per hour, Exhibit 13 is used. Transit Service. For scheduled service of six vehicles per hour or greater the reliability LOS is according to Exhibit 14. LOS Coefficient of Variation A 0.00-0.21 B 0.22-0.30 C 0.31-0.39 Exhibit 12. TCQSM Passenger Load LOS for Bus. D 0.40-0.52 E 0.53-0.74 LOS Standing Passenger Load Factor F 0.75 Area (ft2/p) A >10.8 0.00-0.50 Applies to scheduled service of six or more vehicles B 8.2-10.8 0.51-0.75 per hour. C 5.5-8.1 0.76-1.00 The coefficient of variation is the ratio of the standard D 3.9-5.4 1.01-1.25 deviation of headway deviations divided by the mean E 2.2-3.8 1.26-1.50 scheduled headway. Headway deviations are measured as the actual headway minus the F 1.50 scheduled headway. Adapted from Exhibit 3-26 of the TCQSM. Adapted from Exhibit 3-30 of the TCQSM.