The New Highway Capacity Manual 6 th Edition It s Not Your Father s HCM Tom Creasey, PE, PhD Principal, Stantec Consulting Services Inc. Chair, TRB Highway Capacity and Quality of Service Committee Presented at the 2017 Southern District ITE Meeting March 27, 2017
A Brief History of the HCM 1950: focus on capacity 1965: LOS concept, bus transit chapter 1985: new research, pedestrians, bicycles 1994 & 1997 updates 2000: new research, multiple parts 2010: new research, multimodal focus, four volumes Four emerging topics chapters added after publication
We just published an update in 2010. Why another one? Need for new research Changes in driver behavior, vehicle fleet mix & capabilities, analytical methods, performance measures New research since 2010 truck analysis, managed lanes, reliability, alternative intersections, planning applications Available funding (including SHRP2)
Need for a Major Update to the HCM 2010 The interim chapters, plus other soon-to-becompleted research, needed to be integrated into the HCM Allows the use of all methods in combination Facilitates software development Software facilitates use and implementation The new material would also impact the length of the HCM Thus, a major update was needed
New Research Since HCM 2010 NCFRP 41: truck analysis NCHRP 03-96: managed lanes NCHRP 03-100: roundabouts in corridors NCHRP 03-107: work zone capacity NCHRP 03-115: HCM production NCHRP 07-22: planning guide to HCM SHRP 2 L08: travel time reliability FHWA: ATDM, roundabouts, alternative intersections
Post-2010 Emerging Topics Chapters After HCM 2010 was published, four emerging topics chapters (35 38) were released online (Volume 4) Active Traffic and Demand Management (ATDM) update (Ch. 35) Travel time reliability (Ch. 36, 37) Managed lanes (Ch. 38)
ITE Journal, February 2015 Need for an Updated Title Over the years, HCM content has expanded considerably beyond simply highway capacity Multiple performance measures Many facility types Multimodal analysis Transportation professionals and decision-makers have not always been aware of these additional features 7
Formal Title: Highway Capacity Manual Sixth Edition A Guide for Multimodal Mobility Analysis
6 th Edition Structure Same as 2010 HCM Printed HCM Online Volume 1: Concepts Volume 2: Uninterrupted Flow Volume 3: Interrupted Flow Volume 4: Applications Guide
HCM Volume 1: Concepts Printed Chapters Online Chapter (Vol. 4) 1. HCM User s Guide 2. Applications 3. Modal Characteristics 4. Traffic Operations and Capacity Concepts 5. Quality-of-Service Concepts 6. HCM and Alternative Analysis Tools 7. Interpreting HCM and Alternative Tool Results 8. HCM Primer 9. Glossary and Symbols 36. Concepts: Supplemental
HCM Volume 2: Uninterrupted Flow Printed Chapters Online Chapters (Vol. 4) 10. Freeway Facilities Core Methodology 11. Freeway Reliability Analysis 12. Basic Freeway and Multilane Highway Segments 13. Freeway Weaving Segments 14. Freeway Merge and Diverge Segments 15. Two-Lane Highways 25. Freeway Facilities: Supplemental 26. Freeway and Highway Segments: Supplemental 27. Freeway Weaving: Supplemental 28. Freeway Merges and Diverges: Supplemental
HCM Volume 3: Interrupted Flow Printed Chapters Online Chapters (Vol. 4) 16. Urban Street Facilities 17. Urban Street Reliability and ATDM 18. Urban Street Segments 19. Signalized Intersections 20. Two-Way Stop-Controlled Int. 21. All-Way Stop-Controlled Int. 22. Roundabouts 23. Ramp Terminals and Alternative Intersections 24. Off-Street Pedestrian and Bicycle Facilities 29. Urban Street Facilities: Supplemental 30. Urban Street Segments: Supp. 31. Signalized Int.: Supp. 32. Stop-Controlled Intersections: Supp. 33. Roundabouts: Supp 34. Interchange Ramp Terminals: Supp. 35. Peds & Bikes: Supp.
HCM Volume 4: Applications Guide Available online at hcm.trb.org Open to all, including those who don t have a personal copy of the HCM Must sign up for a free user account to get access 13
Growth in HCM Content Number of Pages Volume 4 466 960 1224 1188 1238 432 512 160 1950 1965 1985 2000 2010 HCM 6 14
Okay, so another HCM Why even use the Manual? Simulation is more accurate and therefore better, right? Methods in the HCM have become too complex. Methods in the HCM are too limited. The Manual has become too large Who has time to read all of that?
Why we should be using the HCM (or using it more frequently) HCM methods thoroughly researched, tested, validated, and peer reviewed on a national scale Range of applications planning, preliminary engineering, design, operations, performance monitoring Guidance on calibrating methods to fit local conditions Some things you cannot do (or do easily) using simulation
HCM 6 th Edition Features Freeway Facilities Method Reliability Multimodal Analysis of Urban Streets Managed Lanes/Active Traffic Demand Management (ATDM) Ramp Terminals and Alternative Intersections Work Zones Planning & Preliminary Engineering Applications Guide
Freeway System Components Off Basic Weave Basic On Off Basic On Historically, these have been evaluated independently Basic Freeway Segments, Weaving Sections, Ramp Merge/Diverge Inability to account for impacts of one element on others
Freeway Facilities Method Segment Type Basic On Basic Off Basic Weave Basic On Off Basic Segment LOS Density* Analysis Period 1 2 3 4 5 6 7 8 9 10 11 A < 11 #1 17:00-17:15 26 31 28 30 27 28 28 34 34 32 29 B > 11-18 #2 17:15-17:30 28 35 32 34 29 32 32 39 39 37 34 C > 18-26 #3 17:30-17:45 30 38 35 36 33 35 37 45 45 44 38 D > 26-35 #4 17:45-18:00 27 32 29 31 27 26 27 33 33 32 28 E > 35-45 #5 18:00-18:15 22 25 23 24 21 19 22 25 25 24 22 F > 45 Section Queue propagation upstream *pc/mi/ln Seg. 1 Seg. 2 Seg. 3 Seg. 4 Seg. 5 Seg. 6 Seg. 7 Seg. 8 Seg. 9 Seg. 10 Seg. 11 Facility Total Length (mi) 1.0 0.3 0.4 0.3 1.0 0.5 1.0 0.2 0.1 0.2 1.0 6.0 Average Travel Time (min) 1.0 0.3 0.4 0.3 1.0 0.6 1.0 0.2 0.1 0.2 1.0 6.3 VMTD (veh-miles / interval) 5,789 1,798 2,733 1,798 5,969 3,322 6,239 1,473 465 1,473 6,464 37,523 VMTV (veh-miles / interval) 5,789 1,798 2,733 1,798 5,969 3,322 6,239 1,473 465 1,473 6,464 37,523 PMTD (p-miles / interval) 5,789 1,798 2,733 1,798 5,969 3,322 6,239 1,473 465 1,473 6,464 37,523 PMTV (p-miles / interval) 5,789 1,798 2,733 1,798 5,969 3,322 6,239 1,473 465 1,473 6,464 37,523 VHT (travel / interval (hrs)) 96.7 33.6 46.4 32.1 100.3 68.9 106.2 28.0 8.8 26.8 111.2 659.1 VHD (delay / interval (hrs)) 0.3 3.6 0.9 2.1 0.8 13.5 2.3 3.4 1.1 2.3 3.4 33.7 Space Mean Speed (mph) 59.8 53.5 58.9 56.0 59.5 48.2 58.7 52.7 52.7 54.9 58.1 56.9 Reported Density (pc/mi/ln) 26.4 27.4 29.3 28.1 27.3 28.2 29.0 29.4 35.3 29.8 30.3 28.4 Max D/C 0.77 0.87 0.87 0.87 0.83 0.77 0.89 0.99 0.99 0.99 0.92 0.99 Max V/C 0.77 0.87 0.87 0.87 0.83 0.77 0.89 0.99 0.99 0.99 0.92 0.99
Reliability Final Rule on National Performance Management Measures (Federal Register, January 18, 2017) Requirement to include a Travel Time Reliability measure in system management and performance monitoring Ability to predict?
More on Reliability Historically, HCM methods have reflected average or typical scenarios Much more variability in real world
Freeway Reliability Analysis Applies Freeway Facilities method repeatedly to develop a travel time distribution Incorporates demand variation, weather, incident, work zone, and special event effects Produces a variety of useful reliability-related performance measures Similar method for Urban Streets Freeway method also evaluates effects of ATDM strategies FREEVAL Computational Engine
Managed Lanes/Active Traffic and Demand Management (ATDM) Strategies HOT/HOV Lanes Reversible Express Lanes Bus Lanes Speed Harmonization Temporary Shoulder Use Ramp Metering
Freeway Facilities Method Applied to Managed Lanes and Other ATDM Strategies Analysis Period Managed Lanes 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 #1 17:00-17:15 12 12 12 12 12 12 12 12 12 12 16 10 10 10 10 1 #2 17:15-17:30 12 12 12 12 12 12 12 12 12 12 16 12 12 12 12 1 #3 17:30-17:45 12 12 12 12 12 12 12 12 12 12 16 11 11 11 11 1 #4 17:45-18:00 11 11 11 11 11 11 11 11 11 11 15 9 9 9 9 1 Analysis Direction Analysis Period General Purpose Lanes 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 #1 17:00-17:15 18 18 16 22 27 24 24 31 29 31 24 24 24 30 45 43 #2 17:15-17:30 24 25 23 27 26 27 27 35 54 45 29 29 29 27 43 40 #3 17:30-17:45 22 22 20 28 37 30 35 54 61 45 30 30 30 28 44 41 #4 17:45-18:00 18 18 16 20 21 19 19 24 26 29 23 23 23 33 41 38 LOS Density* A < 11 B > 11-18 C > 18-26 D > 26-35 E > 35-45 F > 45 *pc/mi/ln
Urban Streets Method Multimodal LOS for autos, bicyclists, pedestrians and bus riders Urban street evaluated as a facility New method for evaluating spillback Includes intersections with interchange ramp terminals (Diamond, ParClo, SPUI, and DCD/DDI) Adjustment factors for N Work area length Drivew ay work zones, midsegment blockage Bay length Median width and downstream Drivew ay spillback Entry taper length Subject direction of travel Speed limit Urban street reliability Width of each lane
Urban Street Segments & Facilities Service measure changed to Average Travel Speed (from ATS as % of FFS) Better spillback method Improved Pedestrian and Bicycle LOS methods Can include roundabouts at ends Segment volumebalancing
Ramp Terminals and Alternative Intersections The former Interchange Ramp Terminals chapter has been expanded to include a greater variety of distributed intersections Two or more intersections with close spacing and displaced or distributed traffic movements that are operationally interdependent and are best analyzed as a single unit 28
Image Source: Kittelson & Associates Ramp Terminals New Interchange Configuration Diverging diamond interchange (DDI) Crossover at each terminal 29
Street Signalized Intersections Chapter 31 provides an improved planning method with reduced input data requirements and simplified calculations General Information Analyst Agency or Company Date Performed Analysis Time Period Intersection Geometry Image Source: Kittelson & Associates PLANNING-LEVEL ANALYSIS: INPUT WORKSHEET Site Information Intersection Jurisdiction Analysis Year Show North = Through = Right = Left = Through + Right Street = Left + Through = Left + Right = Left + Through + Right Volume and Signal Input Required Data Volume (veh/h) Number of lanes Lane use (exclusive or shared) Optional Data 1 Heavy vehicles (%) On-street parking presence (no, yes) Pedestrian activity (none, low, med., high, extreme) Left-turn operation and phase sequence 2 Effective green time (s) 3,4 Progression quality (good, random, poor) 4 EB WB NB SB LT TH RT LT TH RT LT TH RT LT TH RT Peak hour factor Cycle length (s) Base saturation flow rate (pc/h/ln) Notes 1. Optional input data (guidance is provided for estimating these data if they are not known). 2. Combinations addressed: (a) protected operation with left-turn phase, (b) permitted operation no left-turn...phase, (c) protected operation split phasing, (d) protected-permitted operation with left-turn phase 3. Data required for Part I analysis if "protected-permitted operation with left-turn phase" is present. 4. Data required for Part II analysis.
Work Zones New Freeway method for evaluating work zones effects on capacity Urban Streets method provides adjustments to saturation flow rates for mid-block segments and at signalized intersections Procedure for predicting segment queue spillback Work zone activity a key variable in travel time reliability estimation N 1 2 3 Work zone
Application of the Highway Capacity Manual (HCM) The HCM is commonly used by transportation agencies to evaluate current or projected operations The HCM also can reliably and cost-effectively support: Planning efforts Programming decisions Performance monitoring Roadway management Bringing the back of the envelope back
Planning and Preliminary Engineering Applications Guide to the HCM NCHRP Research Project 7-22 Research Team Kittelson & Associates, Inc. Richard Dowling (PI) Paul Ryus ITRE/North Carolina State University Bastian Schroeder Stantec Tom Creasey University of Idaho Michael Kyte REPORT 825 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual 2017 Webinar
Planning in an HCM Context Planning analyses are generally directed toward broad issues Initial problem identification, long-range analyses, statewide performance monitoring Preliminary engineering analyses support moderately detailed issues Planning decisions on roadway design concept and scope, alternatives analyses, and proposed systemwide policies 34
Audiences for the Guide Regular HCM users Planning or preliminary engineering level analyses with limited available data Questions requiring a quick, reasonable answer Planners who may not be aware of the HCM or consider themselves HCM users, but who can nevertheless use it for portions of their work Coordinated use of the HCM with planning models and tools Integration of HCM methods and defaults into planning tools System performance monitoring
Levels of Analysis High level Large analysis area Low detail Medium level Focus on a single roadway facility, segment, or intersection Greater detail Low level Highly focused and highly detailed 36
37 Relative Detail of HCM-Based Analysis Methods
Guide Outline Part 1: Overview Gateway to the Guide for non-hcm users Information cross-referenced throughout the Guide Part 2: Medium-Level Analysis Gateway to the Guide for current HCM users Planning tools for HCM system elements Part 3: High-Level Analysis Guidance on extending the HCM to corridors, areas, and transportation systems Part 4: Case Studies 38
Applications LRTP, TIP development Corridor studies; screening of alternatives Small area transportation plans Travel demand modeling Generalized service volume tables Congestion management plans System performance monitoring, including travel time reliability Predicting traffic control Default values for transportation analyses 39
Case Studies 1. Freeway Master Plan V/C screening of critical segments Prediction of speeds/travel times Queuing estimation System MOEs 2. Arterial Bus Rapid Transit Multimodal Urban Street planning methods Planning-level signalized intersection analysis Trade-offs among various multimodal improvements 40
Case Studies 3. Long Range Transportation Plan FFS, Capacities for Model Input HCM-based Volume-Delay Functions Generalized Service Volume Tables Predicting Reliability 41
Summary Planners have been using Highway Capacity Manual methods in their applications for many years Guidance on using the HCM for planning has been limited through previous editions The Planning & Preliminary Engineering Applications Guide was written specifically for planners The result is planners now have a more robust tool set than ever before for all types of applications 42
Summary HCM 6 th Edition provides more robust tool set than ever before Multimodal analyses Managed lanes Travel time reliability forecasting Roundabouts (based on latest U.S. research) Work zones and ATDM strategies Methods thoroughly researched, tested and peer reviewed
Summary (cont.) HCM 6 th Edition supports variety of applications Planning applications Macroscopic traffic analyses ranging from planning to detailed operations Performance monitoring Guidance on use with simulation Some applications, such as forecasting travel time reliability, cannot be practically performed with simulation
Summary (cont.) HCM 6th Edition and its resources help support the modern practitioner o Concepts and guidance for practitioners o Computational engines for freeway and urban street analysis Applications guides demonstrating how HCM can be applied to actual projects Online Volume 4 with background and supplemental information
Thank you! Tom.Creasey@stantec.com (859)422-1861 Acknowledgements NCHRP 3-115, Production of a Major Update to the 2010 Highway Capacity Manual NCHRP 7-22, Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual