“Bringing Back-of-the-Envelope Back” Planning and Preliminary Engineering Applications Guide (PPEAG) to the HCM “Bringing Back-of-the-Envelope Back” Tom Creasey, PE, PhD Principal, Stantec Consulting Services Inc. Chair, TRB Highway Capacity and Quality of Service Committee 16th TRB National Planning Applications Conference May 15, 2017

HCM Structure Printed HCM Online Volume 1: Concepts The HCM is divided into four volumes: three printed and one online. Volume 1 houses material on concepts that all HCM users should be familiar with before applying the HCM. Volume 2 describes the methodologies for freeways and highways, while Volume 3 describes the methodologies for urban streets and off-street pedestrian and bicycle facilities. Volume 4 provides additional resources that support the material in the printed HCM. We’ll briefly go through the contents of each of these volumes in the next few slides. Later in the webinar, we’ll go over the important changes in the HCM. Volume 1: Concepts Volume 2: Uninterrupted Flow Volume 4: Applications Guide Volume 3: Interrupted Flow 2

Planning and Preliminary Engineering Applications Guide to the HCM Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual REPORT 825 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

Presentation Content Overview Scope and Structure Applications and References Part 1: Guide Overview Part 2: Medium-Level Analyses Part 3: High-Level Analyses Part 4: Case Studies Wrap-Up

Purpose of the Guide The HCM is commonly used by transportation agencies to evaluate the current or forecast operations of roadway facilities Less well known is that the HCM can also be used to cost-effectively and reliably support agencies’ planning, programming, and management decisions

More limited information has been available for planning applications Scope of the HCM The HCM has traditionally focused on describing detailed methods for estimating roadway operational performance Concepts, step-by-step computational methods, example problems More limited information has been available for planning applications Default values, generalized service volume tables, quick estimation methods Throughout its 65-year history, the HCM has focused on describing and demonstrating computational methods for evaluating roadway operations, along with explaining the theoretical concepts underlying the methods. Specific to planning, HCM chapters provide tools such as default values, service volume tables, quick estimation methods, or a combination of these. Although the HCM provides sections in each Volume 2 and 3 chapter outlining HCM methods’ potential use in operations, design, and planning & preliminary engineering applications, the HCM only provides limited guidance on how to apply its methods and tools in the context of a broader decision-making process.

Planning Applications in an HCM Context Evaluation of predicted or forecasted conditions for various facility types Application of HCM methods using combinations of actual data, default values and/or simplifying assumptions More generalized answers (e.g. “Is this sufficient?”) over wider area and/or longer time frame As part of project prioritization Incorporated in performance monitoring

Current Use of the HCM in Planning State DOTs, MPOs, local governments, and others were surveyed Less-experienced users less likely than expert users to see value in using the HCM for planning More use with short-term than long-term planning

Users’ Desired HCM Improvements for Planning Develop a P&PE Applications Guide (77%) Provide travel time reliability measures (63%) Extend HCM to system and corridor analyses (63%) Integrate HCM methods better with travel demand models (60%) Provide systemwide MOEs (60%) The most-desired HCM improvement among the NCHRP synthesis’ survey respondents was to develop an applications guide showing how the HCM could be applied to typical planning and preliminary engineering tasks. As will be discussed in the fourth webinar in the series, the HCM now provides travel time reliability measures. The HCM2000 provided some rudimentrary system and corridor methods, but they required software to be developed to make them practical (which never happened). Those methods therefore received little use and were dropped in the HCM 2010. Other desired improvements included better integration of the HCM with travel demand models and guidance on estimating systemwide measures of effectiveness such as vehicle-hours or person-miles of travel.

Potential Use of the HCM in Planning The HCM is commonly used to evaluate current or forecast roadway operations The HCM can also reliably and cost-effectively support: Planning efforts Programming decisions Performance monitoring Roadway management The Highway Capacity Manual (HCM) is commonly used by transportation agencies to evaluate the current or forecast operations of roadway facilities. Less well known is that the HCM can also be used to cost-effectively and reliably support agencies’ planning, programming, and management decisions.

NCHRP 7-22 Objectives Develop a guide on the use of the Highway Capacity Manual (HCM) for planning and preliminary engineering applications by identifying appropriate methods and applications, illustrating them with case studies. Aspects included: Appropriate use of different parts of HCM for broad spectrum of planning/preliminary engineering applications Use in scenario planning Coordination with other analytical tools Oversaturated conditions in a planning context

Levels of Planning 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 Planning and preliminary engineering covers a wide spectrum of possible levels of analysis. At the highest level (visualize a plane flying at high altitude), the area covered by the analysis is large, but the degree of detail or precision for any particular roadway segment is low. This is a typical characteristic of areawide studies and sketch planning and screening studies. Relatively few data inputs (e.g., volume, number of lanes) are used, but the number of roadways to be analyzed can be challenging, and the precision of the results is low. Medium-level analyses, such as typical HCM analyses, using a mix of measured and default values, have smaller study areas but require a greater variety of data inputs, and the analysis results have a correspondingly higher precision. Microsimulation is an example of a low-level analysis that requires a great deal of time and data, but produces the most detailed results. In general, the level of detail produced by microsimulation is unnecessary for a planning analysis, as many of the data inputs (e.g., future volumes) are not known with great accuracy.

Relative Detail of HCM-Based Analysis Methods Measuring a performance measure directly in the field usually (but not always) results in more accurate analysis results than estimating the measure indirectly using an HCM-based method or other analysis tool, but also requires more resources in terms of time and money. When it is impractical to measure performance in the field, the Guide takes the perspective that an HCM analysis using field-measured inputs is most accurate, followed by an HCM analysis using a mix of default values and field-measured inputs, followed by the alternative analysis methods described in the Guide.

Focus of the Guide Multi- facility Single facility, point The Guide focuses on mid- and high-level analysis methods that either apply the HCM directly or are “HCM-based”—applying simplifications to a method described in the HCM to make it more usable in a planning context by balancing the method’s data needs and computational resources with the level of accuracy needed for the analysis.

Guide’s Relationship to the Project Life Cycle A roadway project goes through many stages from concept to construction to operation. Initially, the potential need for a project is identified through a long- or short-range areawide or corridor-based plan. Later, if selected for further development and if funding is available, a project will move into the project initiation and project clearance stages, and facility-specific project and environmental plans will be developed. Once the project moves into final design, it moves out of the realm of planning and preliminary engineering. However, once the project is constructed and in operation, it becomes part of the overall transportation system and a subject for system performance monitoring. As performance monitoring covers large areas at low levels of precision, planning and preliminary engineering techniques for estimating roadway operations performance measures again become applicable.

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

Organization of the Guide Part 1: Overview (Sections A–G) Entry point to the guide for non-HCM users Menus directing readers to guidebook sections addressing different planning applications Topics referenced throughout the manual Working with traffic demand data Predicting future intersection traffic control Using default values to reduce data needs Using service volume tables to reduce computational effort

Organization of the Guide Part 2: Medium-Level Analysis (Sections H–P) Entry point to the guide for HCM users HCM 6th Edition refers readers to specific guidebook sections Organized by HCM system element Freeways, two-lane highways, urban streets, etc. Plus bicycles, pedestrians, transit, and truck (freight) modes Typical subsections Scoping and screening method HCM method with defaults Alternate or extended HCM method

Organization of the Guide Part 3: High-Level Analysis (Sections Q–S) Extensions of the HCM to larger study areas Corridors Areas and systems Systemwide performance monitoring

Organization of the Guide Part 4: Case Studies (Sections T–V) In-depth examples of applying the Guide’s methods Freeway master plan Arterial bus rapid transit analysis Long-range transportation plan

Applications and References within the PPEAG Organized by planning application instead of method Reference tables associating applications tasks with related sections and case studies Application areas Screening and Scoping Area-wide Transportation Planning Project Impact and Alternatives Analysis System Performance Monitoring

Medium-Level Analysis Tasks Addressed in the Guide Project Impact and Alternatives Analysis Task Reference Sections in Part 3 Related Case Studies in Part 4 Input to travel demand models (if used) Estimate capacities and free-flow speeds R 3.1 Traffic assignment in TDMs (if used) Estimate congested speeds 3.2 Input to microsimulation model (if used) Estimate free-flow speeds H-N None Microsimulation model (if used) validation and error checking Estimate capacity for error-checking simulated bottlenecks Project Impact and Alternatives Analyses Estimate segment speeds for AQ and noise analyses 1.3, 2.4 Estimate auto intersection utilization (v/c ratios) 2.2, 2.3 Estimate delay 2.4 Estimate queuing 1.5, 2.5 Interpret results 1, 2 Analyze travel time reliability H, K 1.6 Estimate quality of service for transit, bicycles and pedestrians O 2.6 Estimate truck level of service P Corridor Analysis Q

Working with Traffic Demand Data Overview Selecting an analysis hour Converting daily volumes to shorter timeframes Seasonal adjustments to traffic volumes Rounding traffic volumes Observed volumes vs. actual demand Constraining demand due to upstream bottlenecks Converting link volumes to turning movements Section D describes methods for working with traffic volume data, both actual counts and estimates produced by travel demand models. This section recognizes that transportation agencies may have already established specific traffic forecasting and analysis policies. In these cases, the Guide recommends that analysts remain consistent with those policies. The guidance provided in this section can be applied in the absence of agency policies, and can also be considered when agencies update their policies.

Predicting Intersection Traffic Control Overview Manual on Uniform Traffic Control Devices (MUTCD) Estimating 8th- and 4th- highest hour volumes Applying MUTCD warrants Graphical method Identifies likely future intersection control for use in a planning analysis Analyzing the operation of an urban street using the HCM requires some knowledge of the type of traffic control used at the intersections along the street. In a planning or preliminary engineering analysis, these decisions may not have been made yet, or the purpose of the analysis may be to determine the likely form of traffic control to be used in the future. Section E provides methods for predicting what the intersection traffic control may be, given estimates of the major and minor street traffic volumes and the directional distribution. This section recognizes that state and local policies may specify the conditions under which particular types of intersection traffic control should or should not be considered, and states that these policies should supersede the guidance presented in Section E.

Default Values to Reduce Data Needs Overview When to consider default values Sources of default values Developing local default values Field Measurements Use Defaults ? A common complaint about HCM methods, particularly in a planning context, is that they require too much data. Default values are a means of reducing an HCM method’s data-collection requirements, while still producing reasonable analysis results. Section F describes the circumstances when an analyst might consider using default values, describes sources of default values, and describes the process for developing local default values. The use of local default values can often improve the accuracy of HCM planning analyses, relative to applying national default values from the HCM, the Guide, or elsewhere.

Service Volume Tables to Reduce Analysis Effort Maximum daily or hourly volume on a roadway facility that achieves a particular level of serviceWhen to consider service volume tables Sources of generalized service volume tables HCM Florida DOT Local tables K- D- Four-Lane Streets Six-Lane Streets Factor LOS C LOS D LOS E Posted Speed Limit = 45 mph 0.09 0.55 16,500 33,600 36,800 25,400 51,700 55,300 0.60 15,100 30,800 33,700 23,400 47,400 50,700 0.10 14,900 30,200 33,100 23,000 46,500 49,700 13,600 27,700 30,300 21,000 42,700 45,600 0.11 13,500 27,500 30,100 20,900 42,300 45,200 12,400 25,200 27,600 19,100 38,800 41,500 A typical planning application of the HCM is to estimate the level of service of a large number of roadway links, as part of a screening evaluation or as part of an agency’s roadway system monitoring program. Service volume tables can simplify this task. Generalized service volume tables present the maximum daily or hourly volume on a roadway facility that achieves a particular level of service. They are called “generalized” tables, because they are constructed by applying standard default values to HCM methods and are applied to a large number of facilities of a given type (e.g., four-lane freeways). It is also possible to create local service volume tables that are more representative of the conditions in a smaller area, using appropriate local default values. Section G describes when service volume tables might be appropriate for an analysis and provides information about three common sources of service volume tables.

Construction of Service Volume Tables HCM Method Representative (default) input values Vary input volumes until service measure threshold is crossed

Construction of Service Volume Tables (cont.) Basic Freeway Segments – Input Values K D % Trucks Ramp Density PHF Terrain Length

Construction of Service Volume Tables (cont.) Example: 6-Lane Freeway, ADT = 85,000  LOS D

Peak-Hour Peak-Direction (veh/h/ln) AADT (2-way veh/day/ln) Scoping and Screening Applying generalized service volume tables Developing service volumes Applicable system elements Freeways Multilane highways Two-lane highways Urban streets Scoping and screening methods involve either the application of existing service volume tables, or determining the maximum volume that can be served at a given level of service. The Guide provides service volume tables for freeways, multilane highways, two-lane highways, and urban streets. Area Type Terrain Peak-Hour Peak-Direction (veh/h/ln) AADT (2-way veh/day/ln) LOS A-C LOS D LOS E (capacity) Urban Level 1,550 1,890 2,150 14,400 17,500 19,900 Rolling 1,480 1,810 2,050 13,700 16,700 19,000 Rural 1,460 1,770 2,010 12,100 14,800 16,800 1,310 1,600 1,820 11,000 13,400 15,200

The HCM doesn’t provide a truck LOS measure Truck Level of Service The HCM doesn’t provide a truck LOS measure NCFRP Report 31 does, and it has been incorporated into the Guide Truck LOS is based on the degree to which a roadway provides ideal truck conditions Usable by trucks with legal size and weight loads No at-grade railroad crossings Provides reliable truck travel at truck free-flow speeds Low cost (i.e., no tolls) The HCM does not yet provide a truck LOS measure. However, such a measure has been developed through research and is presented in National Cooperative Freight Research Program Report 31, Incorporating Truck Analysis Into the Highway Capacity Manual. The Guide describes the data requirements and calculation steps for the method, which can be implemented by hand or in a spreadsheet. Truck LOS is based on the degree to which a roadway provides ideal truck conditions, as defined in the slide.

Travel Time Reliability New FHWA Final Rule on National Performance Management Measures and Assessing Performance of the National Highway System Includes Travel Time Reliability Historically, HCM methods have reflected average or “typical” scenarios Much more variability in “real world”

HCM Reliability Analysis Applies Freeway Facilities and Urban Streets methods repeatedly with adjusted demands, capacities, lanes, and free-flow speeds 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

PPEAG Reliability Method Simplification of HCM Operational Method Two measures 95th percentile Travel Time Index (Planning Time Index, or TTI95 Pct. Trips < 45 mph Estimated as function of: Free-flow speed Peak hour speed Peak hour V/C ratio

Case Studies Freeway Master Plan Arterial Bus Rapid Transit V/C screening of critical segments Prediction of speeds/travel times Queuing estimation System MOEs Arterial Bus Rapid Transit Multimodal Urban Street planning methods Planning-level signalized intersection analysis Trade-offs among various multimodal improvements Recognizing the breadth of the Guide’s target audience, the Guide has been structured so that it can been approached in different ways. Importantly, the Guide is designed as a reference work that is not intended to be read cover to cover. Non-HCM users access the Guide via Part 1, while HCM users are referred to appropriate parts of the Guide directly from the HCM 6th Edition. These gateways then refer readers to appropriate sections in Parts 1–4 for more information and examples. In addition to providing an overview of the Guide, Part 1 addresses topics cross-referenced throughout the Guide. Part 2 is divided into sections corresponding to HCM system elements (e.g., freeway facilities or signalized intersections), and also provides sections on multimodal analysis and truck level of service. Part 3 provides guidance on extending the HCM to larger study areas, including corridors, areas, and entire transportation systems. Finally, Part 4 provides three case studies demonstrating many of the methods provided in the Guide. The remainder of this webinar will cover each of these parts in detail.

Case Studies Long Range Transportation Plan FFS, Capacities for Model Input HCM-based Volume-Delay Functions Generalized Service Volume Tables Predicting Reliability Recognizing the breadth of the Guide’s target audience, the Guide has been structured so that it can been approached in different ways. Importantly, the Guide is designed as a reference work that is not intended to be read cover to cover. Non-HCM users access the Guide via Part 1, while HCM users are referred to appropriate parts of the Guide directly from the HCM 6th Edition. These gateways then refer readers to appropriate sections in Parts 1–4 for more information and examples. In addition to providing an overview of the Guide, Part 1 addresses topics cross-referenced throughout the Guide. Part 2 is divided into sections corresponding to HCM system elements (e.g., freeway facilities or signalized intersections), and also provides sections on multimodal analysis and truck level of service. Part 3 provides guidance on extending the HCM to larger study areas, including corridors, areas, and entire transportation systems. Finally, Part 4 provides three case studies demonstrating many of the methods provided in the Guide. The remainder of this webinar will cover each of these parts in detail.

The Guide can be downloaded from HCM Volume 4 Resources The Guide can be downloaded from HCM Volume 4 www.hcmvolume4.org Free, one-time registration required Guide also can be downloaded at http://www.trb.org/Publications Five spreadsheet computational engines provided on Volume 4 to help implement some of the Guide’s methods The Guide can be downloaded from the Applications Guides section of online HCM Volume 4, which is free to access by all, including those who don’t have a personal copy of the HCM. A free, one-time registration is required. In addition to providing access to the Guide itself, the same web page currently provides five spreadsheet-based computational engines that help implement some of the Guide’s methods. In addition, additional outreach and training materials supporting the Guide are currently in development and will be posted on Volume 4 as they completed during 2017. Printed copies of the guide (NCHRP Report 825) can be ordered from the Transportation Research Board.

Summary The Guide provides a resource for both HCM users and planning professionals to: Conduct quick back-of-the-envelope evaluations where neither a full HCM analysis nor simulation is necessary Maintain consistency with the HCM throughout the project development process Incorporate HCM methods into planning tools Develop inputs used by planning models Improve the accuracy and consistency of computations performed by planning models Post-process model outputs to generate additional performance measures To wrap up, the Guide is a resource for both transportation engineers and transportation planners, including those who may not consider themselves to be HCM users. It provides methods for conducting quick back-of-the-envelope evaluations for analyses that do not require the level of precision provided by a full HCM operations analysis or by simulation. Because these methods are based on full HCM methods, the methods’ results will be consistent with those obtained from full HCM operations analyses performed later in the project development process, to the extent that the same assumptions are used. The Guide also provides guidance on incorporating HCM methods into planning tools, including developing input values used by planning models, improving the accuracy and consistency of computations performed by planning models, and post-processing model outputs to develop additional performance measures.

Future TRB Webinars on the PPEAG Part 1, Contents Tuesday, May 30, 2017 from 2:00-3:30PM ET Part 2, Applications Wednesday, June 28, 2017 from 2:00-3:30PM ET For more information: http://www.trb.org/Calendar

Questions? This concludes the webinar presentation. We now invite the audience to ask questions about the material that was covered. 40