HCM – Sixth Edition Introducing the Planning & Preliminary Engineering Applications Guide to the HCM Today’s web briefing introduces the Planning & Preliminary.

HCM – Sixth Edition Introducing the Planning & Preliminary Engineering Applications Guide to the HCM Today’s web briefing introduces the Planning & Preliminary Engineering Applications Guide to the Highway Capacity Manual. Month Day, 2016

Instructor Note: Instructor should show their name, title, affiliation, and HCM-related background. If the presentation is via webinar, then add a photo of instructor. My name is: _______________. I will be the instructor for today’s presentation. I am a _______________ with ____________.

Briefing Series Overview
What’s New – HCM 6th Edition New Features in Freeway Analysis Chapter Freeway Reliability and Strategy Assessment Urban Streets Segment Chapter Urban Streets Facility Chapter Signalized Intersection Chapter Signalized Intersection Planning Method Roundabouts Ramp Terminals and Alternative Intersections Planning and Preliminary Engineering Applications Guide to the HCM Today’s briefing is the last in a series of ten briefings on the recently released Highway Capacity Manual (HCM) 6th Edition. It introduces a companion document to the HCM, the Planning and Preliminary Engineering Applications Guide, that provides guidance and case studies on the potential use of HCM methods in a planning and preliminary engineering context.

Learning Objectives Describe what “planning” and “preliminary engineering” mean in an HCM context Understand why the Guide was developed, its intended audience, and its general structure Identify the planning tasks to which HCM methods can potentially be applied Learn about the case studies provided in the Guide and how they demonstrate the application of HCM planning methods to a variety of planning tasks The objectives of today’s briefing are four-fold. First, you should be able to describe what “planning” and “preliminary engineering” mean in an HCM context. Second, you should understand why the guide was developed, its intended audience, and its general structure. Third, you will learn about a variety of planning tasks to which HCM methods can be applied. Finally, you will see how the Guide’s case studies demonstrate the Guide’s methods in the context of typical planning tasks.

“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 Before jumping into the presentation, it will be useful to define what planning and preliminary engineering is in an HCM context. In an HCM context, planning analyses are generally directed toward broad issues that involve analyzing a large number of facilities. The purpose of the analysis may be to identify facilities that may have existing or future operational issues and require more a detailed analysis. In this case, HCM methods are used to screen out facilities that are unlikely to have problems, allowing analysis resources to be focused on the potential problem areas. HCM planning analysis techniques are also applicable to statewide performance monitoring, where the performance of a large number of facilities needs to be summarized. Preliminary engineering analyses support moderately detailed issues, such as identifying the required number of lanes to provide a given level of service and conducting a more-detailed analysis of a limited set of alternatives. These types of analyses can also investigate the potential effects of proposed systemwide policies such as lane use control for heavy vehicles, systemwide freeway ramp metering and other intelligent transportation system applications, and the use of demand management techniques. The HCM also defines ”design” and ”operations” levels of analyses that are more detailed and beyond the scope of the Planning & Preliminary Engineering Guide; we’ll cover these briefly later in the presentation.

Presentation Overview
Need for the P&PE Applications Guide Guide Scope and Structure Part 1: Overview Part 2: Medium-Level Analysis Part 3: High-Level Analysis Part 4: Case Studies We are now ready to move onto the topic of today’s briefing: Introducing the Planning & Preliminary Engineering Applications Guide to the HCM. For convenience, I will generally refer to the document as the “Guide” from this point on. I will start with a brief overview of why the Guide is needed.

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 According to the introduction to the Guide, 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. [Replace image with an HCM 6th Edition cover when available]

Actual 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 A survey described in Naitonal Cooperative Highway Research Program Synthesis 427, Extent of Highway Capacity Manual Use in Planning, provided valuable insights on how the HCM is and is not used for planning. Less-experienced users—those who had a self-described familiarity with the HCM ranging from little to average—were less likely to see value in using the HCM for planning. This suggests that more education is needed to familiarize less-experienced professionals with the potential benefits of using the HCM in planning. When the HCM was used for planning, it was more often in the context of short-term planning (where more inputs to HCM procedures would be known with certainty) than for long-term planning. Note that at the time the survey was made, users were familiar with the HCM2000; the HCM 2010 was released a couple of months after the survey.

Users’ Desired HCM Improvements for Planning
Develop a P&PE Applications Guide (77%) Provide travel time reliability measures (63%) Extend HCM to system & corridor analyses (63%) Integrate HCM methods better with travel demand models (60%) Provide systemwide MOEs (60%) The most-desired HCM improvement among the survey respondents was to develop an applications guide showing how the HCM could be applied to typical planning and preliminary engineering tasks. As discussed in another briefing, 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 and therefore received little use and were dropped in the HCM 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.

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 provides 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.

HCM Applications Guidebook
The HCM explains computational methodologies in great detail, but provides little guidance on their potential application The HCM Applications Guidebook (HCMAG) was developed to meet this need for operations and design analyses Available in online HCM Volume 4 To address the need for more guidance on how to apply the HCM in the context of a larger operations or design study, the HCM Applications Guidebook was developed in This guide is available as part of the online HCM Volume 4. [Provide link to Volume 4 when the new address is determined]

HCM Applications Guidebook
The HCMAG presents six case studies demonstrating typical HCM applications to operations & design Focus is on selecting appropriate methods, gathering data, and interpreting results The HCMAG presents six case studies, each of which focuses on a common HCM operations or design application. Each case study, in turn, consists of several problems that address individual issues that might to be analyzed as part of a transportation study. Unlike the HCM, which provides example problems for the purpose of demonstrating how to perform a method’s calculations, the HCMAG’s problems focus on the process—where to obtain data, how to deal with missing data, and how to interpret and apply the results. It was thought that similar guidance providing case studies on applying the HCM to planning and preliminary engineering applications would be useful.

Objectives for a Planning Guide
NCHRP Project was funded to develop a planning counterpart to the HCMAG that would describe: Appropriate use of the HCM to a broad spectrum of planning applications Use of default values and other HCM tools Use of the HCM in scenario planning Coordinated use of HCM with planning models Use of the HCM in evaluating oversaturated conditions in a planning context National Cooperative Highway Research Program project was funded to develop a Planning & Preliminary Applications Guide to the HCM that would describe how the HCM could be applied to a wide variety of planning, preliminary engineering, and performance management applications, including but not limited to the use of default values and service volume tables; HCM use in scenario planning; HCM use with travel demand, noise, and air quality models; and the evaluation of over-capacity conditions in a planning context.

Need for the P&PE Applications Guide Guide Scope and Structure Part 1: Overview Part 2: Medium-Level Analysis Part 3: High-Level Analysis Part 4: Case Studies We will now move on to today’s second topic: the scope of the Guide and its structure.

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 segment of road is low. This is a typical characteristic of regional 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 precision.

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 (balancing data needs and computational resources with the required accuracy for an analysis.

Guide’s Relationship to the Planning Process
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.

Target Audience for the Guide
Every technical professional involved in estimating the need for, and benefits of, highway capacity, monitoring, management, and operations investments. All current HCM users Planners and travel demand modelers who may not consider themselves HCM users Many planning models use (or can use) pieces of the HCM as inputs to, or calculations within, the model Travel demand, air quality, noise modeling University students in transportation engineering and planning programs Given the broad range of planning and preliminary engineering analyses, the target audience for the Guide is equally large. It includes all current HCM users, planners and modelers who may not consider themselves HCM users, as well as university students in transportation engineering and planning programs.

Part 2: Medium-Level Analysis
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 (points, segments, facilities) Part 3: High-Level Analysis Guidance on extending the HCM to corridors, areas, and transportation systems Part 4: Case Studies 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. 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 provides sections on topics cross-referenced throughout the Guide. Part 2 is divided into sections corresponding to HCM system elements (e.g., freeway facilities or signalized intersections), plus 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 web briefing will cover each parts in detail.

Guide scope and structure Questions on these topics?
Need for the Guide Guide scope and structure Questions on these topics? Before exploring the Guide in more detail, let’s take a few minutes to answer questions on the need for the Guide and the Guide’s scope and structure. 21

Need for the P&PE Applications Guide Guide Scope and Structure Part 1: Overview Part 2: Medium-Level Analysis Part 3: High-Level Analysis Part 4: Case Studies We will now begin to explore the Guide’s contents, starting with Part 1: Overview.

B. Medium-Level (Facility-Specific) Analyses C. High-Level Analyses
Part 1 Outline A. Introduction B. Medium-Level (Facility-Specific) Analyses C. High-Level Analyses D. Working with Traffic Demand Data E. Predicting Intersection Traffic Control F. Default Values G. Service Volume Tables To avoid confusion with the HCM’s volume and numbered chapter structure, the Guide is organized by parts and lettered sections. Part 1 contains 7 sections. Section A provides an introduction to the guide. Sections B and C are the gateway to the Guide for planners and modelers. Sections D through G provide reference information used throughout the Guide. [Replace placeholder with an image of the PPEAG cover]

Section A: Introduction
Overview Scope of the Guide Definitions Applications Levels of analysis Relationship to the Guide to the project life cycle Target audience How to use the Guide Hierarchy of analysis methods Section A provides an introduction to the guide. As we’ve already covered these topics earlier in this web briefing, we will not go through them again.

Section B: Medium-Level (Facility-Specific) Analyses
Overview Project traffic and environmental impact studies Typical process Typical analysis tools Basic data needs How the HCM can support these types of analyses Applications of default values Section B is a gateway to the Guide for planners and engineers working on project traffic and environmental impact studies. It describes the general process followed in completing these studies, the typical analysis tools used, and typical data needs. It then provides a table that lists typical analysis tasks for project traffic and environmental impact studies and points the reader to the appropriate sections of the Guide where HCM-based analysis tools for performing these tasks are described and illustrated. The section concludes with an introduction to default values (i.e., standard input values to HCM methods for use when an actual value is not known) and cross-references to sections of the Guide where default values are covered in more detail.

Medium-Level Analysis Tasks Addressed in the Guide
Project Impact and Alternatives Analysis Task Parts 2 and 3 Reference Part 4 Case Studies Input to travel demand models (if used) Estimate highway capacities and free-flow speeds Section R Case Study 3.1 Traffic assignment module within travel demand model (if used) Apply volume–delay functions for estimating congested speeds Case Study 3.2 Input to microsimulation model (if used) Estimate free-flow speeds Sections H-N None Microsimulation model validation and error checking (if used) Estimate capacity for error checking simulated bottlenecks Project impact and alternatives analyses Estimate segment speeds for air quality and noise analyses Case Studies 1.3, 2.4 Estimate auto intersection utilization (v/c ratios) Case Studies 2.2, 2.3 Estimate delay Case Study 2.4 Estimate queuing Case Studies 1.5, 2.5 Interpret results Case Studies 1, 2 Analyze travel time reliability Sections H, K Case Study 1.6 Estimate multimodal quality of service for transit, bicycles, and pedestrians Section O Case Study 2.6 Estimate truck level of service Section P Corridor analyses Section Q This table in Section B shows the types of medium-level analysis tasks where the HCM may be applicable. Tasks include preparing inputs to other tools used in the analysis, such as travel demand models, microsimulation tools, and air quality and noise models. They also include directly estimating specific operations performance measures such as volume-to-capacity ratios, delay, queueing, travel time reliability, and multimodal quality of service. The table cross-references the Part 2 and 3 sections where planning-level methods are described, and the Part 4 case studies (if any) where the methods are demonstrated.

Section C: High-Level Analyses
Overview Screening and scoping studies Roles of the HCM and the Guide Long- and short-range areawide transportation planning Typical process, tools, data needs How the HCM can support these types of analyses System performance monitoring Context Section C is a gateway to the Guide for planners and engineers working on screening and scoping studies, long- and short-range areawide transportation plans, and system performance monitoring tasks. Similar to Section B, this section provides tables describing typical analysis tasks, with cross-references to appropriate sections of the Guide providing methods and case studies.

Screening and Scoping Tasks Addressed in the Guide
Parts 2 and 3 References Part 4 Case Studies Identify potential level of service (LOS) hot spots Screen for auto LOS problems Sections H-N Case Studies 1.4, 2.4 Screen for truck LOS problems Section P None Screen for transit, bicycle, and pedestrian LOS problems Section O Case Study 2.6 Identify potential capacity problems: auto Case Studies 1.1, 1.2, 2.1, 2.2, 2.3 Preliminarily evaluate improvement alternatives Auto improvements Case Study 1.7 Truck improvements Transit, bicycle, and pedestrian improvements Screening and scoping tasks addressed in the Guide include identifying potential level of service hot spots by mode, identifying potential capacity problems for the automobile or motorized vehicle mode, and preliminary evaluating improvement alternatives by mode.

Areawide Transportation Planning Tasks Addressed in the Guide
Areawide Planning Analysis Task Part 3 Reference Part 4 Case Study Input to travel demand models Estimate highway segment capacities and free-flow speeds Section R Case Study 3.1 Traffic assignment module within the travel demand model Apply volume–delay functions to estimate congested speeds Case Study 3.2 Post-processing travel demand model outputs Obtain more accurate speed estimates for air quality analyses Case Study 3.3 Spot auto volume-to-capacity and level of service hot spots (quick screening) Estimate delay based on agency policy Estimate queuing Interpret results Analyze travel time reliability Case Study 3.4 Estimate multimodal quality of service for autos, trucks, transit, bicycles, and pedestrians None Corridor analyses Section Q Areawide transportation planning tasks addressed in the Guide include preparing HCM-compatible capacity and free-flow speed inputs to travel demand models, applying HCM-compatible volume–delay functions to estimate congested speeds, and post-processing travel demand model outputs to estimate specific operations performance measures. Using HCM-compatible methods is useful at the planning stage, as the HCM will often be used in the next step of the project life cycle to evaluate identified transportation needs in more detail. Using HCM-compatible planning methods makes it more likely that subsequent analyses that apply HCM operational methods will confirm previously identified needs and will avoid having to redo screening work to make sure that no needs were overlooked.

System Performance Monitoring Tasks Addressed in the Guide
Part 3 Reference Part 4 Case Study Estimate monitoring site capacities and free-flow speeds Section R4 Case Study 3.1 For volume-only monitoring sites Estimate speeds Section R5 Case Study 3.2 For travel time–only monitoring segments Estimate congestion Section S3 None Performance analyses Auto and truck VMT by level of service Estimate delay Case Study 3.3 Estimate queuing Analyze travel time reliability Case Study 3.4 Estimate multimodal level of service for transit, bicycles, and pedestrians Estimate truck level of service Performance monitoring of the federal-aid highway system is a requirement introduced by the MAP-21 federal highway bill. HCM analysis techniques are relevant to the MAP-21 goal areas of Congestion Reduction, System Reliability Improvement, and Freight Movement. The HCM can be used to compute the performance measures not directly monitored at a monitoring site. It can be used to spot data errors and inconsistencies. It can also be used to impute missing performance data.

Section D: 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 for upstream bottleneck metering 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 state and local transportation agencies may have already established specific traffic forecasting and analysis guidelines and policies and recommends that analysts remain consistent with those policies, where they exist. The guidance in this section can be applied in the absence of agency policies, and can also be considered when agencies update their policies.

Section E: 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.

Section F: Default Values to Reduce Data Needs
Overview When to consider default values Sources of default values Developing default values 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, in comparison to applying national default values from the HCM, the Guide, or elsewhere.

Section G: Service Volume Tables to Reduce Analysis Effort
Overview Description When to Consider Service Volume Tables Sources of Generalized Service Volume Tables HCM Florida DOT Local tables 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 considered for an analysis and provides information about three common sources of service volume tables.

Common planning tasks amenable to HCM methods
Questions Common planning tasks amenable to HCM methods Working with traffic volumes Predicting intersection control Default values Service volume tables Questions on these topics? This concludes our tour of Part 1 of the Guide. Before continuing on to Part 2, let’s take a few minutes to answer questions on the topics contained in Part 1. 35

Need for the P&PE Applications Guide Guide Scope and Structure Part 1: Overview Part 2: Medium-Level Analysis Part 3: High-Level Analysis Part 4: Case Studies Our exploration of the Guide now continues with Part 2: Medium-Level Analysis.

L. Signalized Intersections M. Stop-Controlled Intersections
Part 2 Outline H. Freeway Analyses I. Multilane Highways J. Two-Lane Highways K. Urban Streets L. Signalized Intersections M. Stop-Controlled Intersections N. Roundabouts O. Pedestrians, Bicyclists, and Public Transit P. Truck Level of Service Part 2 contains 9 sections and is likely to be the first point of entry to the Guide for regular users of the HCM. Each HCM chapter presenting an analysis methodology cross-references the Part 2 section in the Guide that contains the corresponding planning guidance and methods. Sections H–N each cover one of the main types of HCM roadway system elements from the perspective of motorized vehicle operations. They are structured similarly and we’ll look at them as a group in a moment. Section O provides planning methods for the pedestrian, bicycle, and public transit modes for all of the system elements for which the HCM provides methods. Finally, Section P presents a method for estimating truck level of service that fills a gap in the HCM’s analysis toolbox. [Replace placeholder with an image of the PPEAG cover]

Typical Part 2 Section Outline
Overview Applications Analysis Methods Overview Scoping and Screening Method Section Analysis Applying the HCM with Defaults Simplified HCM Facility Method Reliability (freeways, urban streets, signals) Multimodal LOS cross-reference Case study cross-reference Sections H–N have similar outlines, although not every section covers every topic listed above, and some sections cover additional topics. The first three subsections define the system element described in the section, list the potential planning and preliminary engineering applictions that the Guide’s methods can be applied to, and list the analytical methods covered in more detail in the remainder of the section. We’ll look at these methods over the next few slides. The freeway and urban street sections (and, to a lesser extent, signalized intersections) provide methods for estimating a variety of travel time reliability measures. The sections conclude with cross-references to the multimodal level of service methods for the system element in Sections O and P, and to applicable case studies in Part 4.

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

Section Analysis Using the HCM with Defaults
Applies the HCM operations method, but using default values for many inputs to reduce data requirements Requires access to HCM-implementing software Guide provides information on what input data are needed to apply the method Guide suggests default values for inputs that can be defaulted Applicable system elements: Freeways, multilane highways, two-lane highways Urban streets Regular HCM users typically have access to software that implements the HCM operations methods for various system elements. In these cases, a planning or preliminary engineering analysis can be performed by substituting default values for many or all of the inputs that are not required to be provided (such as demand volumes or number of lanes). The Guide provides tables that compare the data required for an HCM analysis using defaults (with software) and a simplified HCM analysis (by hand, by spreadsheet, or a calculation incorporated into another analysis tool). These tables also suggest default values for inputs that can be defaulted; some tables provide more suggested defaults than the HCM itself provides.

Example Data Requirements for Multilane Highways
Input Data (units) For HCM Section For Facility Method Default Value Hourly directional volume (veh/h) • Must be provided Number of directional lanes Terrain type (level, rolling, etc.) Must be provided* Lane width (ft) 12 Total lateral clearance (ft) Access points/mile 8 (rural), 16 (low-density suburban), 25 (high-density suburban) Free-flow speed (mph) Percentage heavy vehicles (%) 10 (rural), 5 (suburban)** Peak hour factor (decimal) 0.88 (rural), 0.95 (suburban) Section length (mi) Intersection performance data This table from the Guide compares the data requirements for evaluating sections of multilane highways between major intersections and for evaluating longer facilities. It lists the basic inputs that must be provided—in this case, volume, lanes, terrain type, and free-flow speed, along with suggested default values for the other inputs used by the method. Of the four required inputs, the first three should be readily available to the analyst, while the Guide provides three suggested methods (in order of descending accuracy) for estimating free-flow speed from data available to the analyst.

Most HCM operations methods require specialized software to implement
Simplified HCM Method Most HCM operations methods require specialized software to implement Many target users of the Guide won’t have access to this software Using the HCM method with defaults may require more resources than available or appropriate for the analysis The Guide presents simplified methods that are HCM-compatible, but can be performed by hand or implemented in a basic spreadsheet Multiple performance measures can be calculated Simplified methods available for all system elements Many target users of the Guide won’t have access to specialized software implementing HCM methods. Even when software is available, it may require more data collection than is feasible or appropriate for the level of analysis being conducted. Consequently, the Guide presents simplified HCM methods for each of the system elements covered in the Guide. These methods are based on HCM methods, but unlike most full HCM methods, the calculations can be performed by hand, implemented using formulas in a spreadsheet (no macro programming required), or incorporated as a calculation routine in another analysis tool. Multiple performance measures can be calculated and the analyst need only provide the data required to calculate the performance measures of interest, as opposed to the data required to calculate the full suite of measures produced by an HCM method.

Example Data Requirements for the Simplified Signalized Intersection Method
Performance Measure Input Data (units) Cap Del LOS MMLOS Que Default Value Number of turn lanes • Must be provided Other geometry HCM Exhibit 19-11 Signal timing HCM Exhibits and 19-17 Peak hour factor (decimal) 0.90 (total entering volume <1,000 veh/h), 0.92 (otherwise) Percentage heavy vehicles (%) 3% Parking activity None Pedestrian activity Volumes by movement (veh/h) Analysis period length (h) 0.25 h This table from the Guide compares the data requirements for estimating different performance measures for signalized intersections using the Guide’s simplified method. In contrast, the table of data requirements for the full HCM operations method is more than a page long. Of the required data, only one or two items must be provided by the analyst (number of turn lanes and turning movement volumes), while the remaining inputs can be defaulted if the corresponding data are not available to the analyst. In the case of the signalized intersection method, the Guide provides step-by-step calculations for estimating capacity, delay, auto level of service, multimodal level of service, and queue lengths. The calculations can be implemented in a spreadsheet, or performed by hand using the worksheets provided in the Guide. The goal of the simplified methods is to provide reasonably accurate results with much less data collection and compuational effort. Cap = capacity, Del = delay, LOS = motorized vehicle level of service, MMLOS = multimodal level of service, Que = queue length

Other Topics: Sections H–N
Freeways Method adaptations for advanced freeway management practices Urban streets Method extension to over-capacity conditions Many target users of the Guide won’t have access to specialized software implementing HCM methods. Even when software is available, it may require more data collection than is feasible or appropriate for the level of analysis being conducted. Consequently, the Guide presents simplified HCM methods for each of the system elements covered in the Guide. These methods are based on HCM methods, but unlike most full HCM methods, the calculations can be performed by hand, implemented using formulas in a spreadsheet (no macro programming required), or incorporated as a calculation routine in another analysis tool. Multiple performance measures can be calculated and the analyst need only provide the data required to calculate the performance measures of interest, as opposed to the data required to calculate the full suite of measures produced by an HCM method.

Section O: Pedestrians, Bicyclists, and Public Transit
Freeways Multilane and Two-Lane Highways Urban Streets Signalized Intersections Stop-Controlled Intersections Roundabouts Off-Street Pathways Section O presents planning methods for evaluating pedestrian, bicycle, and/or transit performance (typically LOS) for the system elements covered in Sections H–N, plus off-street pathways. In some cases, methods for estimating additional performance measures, such as speed, delay, or capacity, are also provided. Not every mode is addressed in every subsection, either because the combination isn’t applicable (for example, pedestrians on freeways) or because the HCM does not yet provide a method (or an extendable method) for that combination (for example, bicycle LOS at roundabouts).

Section P: 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 above.

Need for the P&PE Applications Guide Guide Scope and Structure Part 1: Overview Part 2: Medium-Level Analysis Part 3: High-Level Analysis Part 4: Case Studies Our exploration of the Guide now continues with Part 3: High-Level Analysis.

Q. Corridor Quick Estimation Screenline Analysis R. Areas and Systems
Part 3 Outline Q. Corridor Quick Estimation Screenline Analysis R. Areas and Systems S. Roadway System Monitoring Part 3 contains 3 sections that extend HCM methods to the analysis of corridors, areas, and systems. [Replace placeholder with an image of the PPEAG cover]

Section Q: Corridor Quick Estimation Screenline Analysis
Quick method for assessing corridor capacity More-detailed assessments would use Section R (area) techniques or facility-specific methods from Part 2 The performance of a freeway–arterial corridor system and its components are often estimated through a travel demand and analysis forecasting process combined with either a microscopic or macroscopic traffic operations model. This process requires a variety of inputs and outputs which the HCM can provide, including capacity, queues, delay, travel speeds, and level of service. Section Q provides a quick, high-level method for assessing corridor capacity. A more-detailed, but still planning-level assessment can be conducted using either the area techniques discussed in Section R or the facility-specific methods from Part 2.

Section R: Areas and Systems
Area- and systemwide analysis is typically performed in a travel demand modeling environment Section R provides guidance on: Using HCM procedures to generate the key performance analysis inputs required by typical demand models Post-processing demand model output to generate additional performance measures Although the HCM is not typically used directly for area- and systemwide analysis, it can be applied during a travel demand modeling process to both develop more-accurate capacity inputs to the model and to generate additional performance measures not directly output by the model. Section R provides guidance on both these aspects of area- and systemwide analysis.

Section S: Roadway System Monitoring
Guidance on identifying and diagnosing travel-time reliability and capacity problems Method assumes that the agency has access to archived average travel times by road segment and time of day The travel time index, the ratio of actual to free-flow travel time, is a useful indicator of congestion problem spots Florida DOT Section S provides guidance on calculating a roadway segment’s travel time index from archived travel time data and interpreting the results in terms of whether a roadway link is likely, possibly, or unlikely to be congested.

Planning methods for HCM system elements Multimodal planning methods
Questions Planning methods for HCM system elements Multimodal planning methods Truck level of service Corridors, areas, and systems Performance monitoring Questions on these topics? This concludes our tour of the planning methods provided in Parts 2 and 3 of the Guide. Before moving on to the final portion of today’s presentation, let’s take a few minutes to answer questions on the topics contained in Parts 2 and 3. 52

Need for the P&PE Applications Guide Guide Scope and Structure Part 1: Overview Part 2: Medium-Level Analysis Part 3: High-Level Analysis Part 4: Case Studies This web briefing now concludes with a tour of the case studies provided in Part 4 of the Guide.

T. Case Study 1: Freeway Master Plan
Part 4 Outline T. Case Study 1: Freeway Master Plan U. Case Study 2: Arterial Bus Rapid Transit Analysis V. Case Study 3: Long-Range Transportation Plan Analysis Part 4 contains 3 case studies that illustrate the application of many of the methods presented in Parts 2 and 3 of the Guide. The case studies cover the analysis of a 70-mile section of freeway, a proposed new bus rapid transit route (with exclusive bus lanes) along a series of urban streets, and the application of HCM methods to a long-range transportation plan. [Replace placeholder with an image of the PPEAG cover]

Section T: Case Study 1—Freeway Master Plan
Master plan covers a 70-mile stretch of U.S. 101 in San Luis Obispo County, California Mostly four-lane freeway, with a six-lane section over a hill, and some multilane highway sections Objective of the planning analysis is to identify current and future problem areas and to prioritize projects for future capital programming Seven example problems Case Study 1 provides seven example problems that demonstrate how HCM planning techniques can be applied to the analysis of a 70-mile stretch of U.S. 101 along California’s central coast. The facility is primarily a four-lane freeway, but some portions are classified as multilane highways due to the presence of at-grade intersections and climbing lanes are provided where the roadway climbs a 7% grade over a hill.

Section T: Case Study 1—Example Problem 1
Facility is split into supersections on the basis of similar demand volumes, terrain, facility type, and number of lanes Nine supersections ranging from 3 to 13 miles in length Service volumes for LOS D and E calculated using local heavy vehicle percentages and traffic peaking characteristics Supersections operating at LOS D or worse identified Example Problem 1 demonstrates how the study area is divided into nine supersections on the basis of similar demand volumes, terrain, facility type (freeway or multilane highway), and number of lanes. It identifies the required data for the analysis and demonstrates how to identify the maximum service volume for a given LOS, using local values for heavy vehicle percentage, driver population, and traffic peaking characteristics. The demand volumes for each section are compared to the service volume and the three supersections where the service volume is exceeded are flagged for more detailed analysis. The remaining example problems focus on one of these supersections, Supersection C, a five-mile stretch of rural freeway connecting the cities of San Luis Obispo and Pismo Beach.

Supersection C is split into 7 sections between ramps Each section’s per-lane capacity is determined Per-lane demand volumes are compared to per-lane capacity Bottlenecks where demand exceeds capacity meter demand to the downstream section Bottlenecks can be flagged for further analysis (e.g., analyzing mitigation options) Example Problem 2 demonstrates how to identify ”hot spots” along the facility where demand exceeds capacity. The supersection is split into sections, with section boundaries occuring at on- and off-ramps. The per-lane capacity of each section is then determined. Starting with the mainline demand entering the supersection, per-lane demand volumes are compared to each segment’s per-lane capacity. If demand exceeds capacity, a bottleneck is identified, and demand to the next downstream section is metered by the section’s capacity.

Speeds and travel times are determined for each section within the supersection The only input required for estimating speed is the demand-to-capacity ratio Travel times also require knowing the section length Average speed and overall travel time can be determined for the supersection as a whole Results can be tabulated or shown in a contour diagram Example Problem 3 illustrates speed and travel time calculations. The only input required to estimate speed is the demand-to-capacity ratio, which was determined in the previous example problem. Average speed and overall travel time can be determined by time period for the supersection as a whole, and the results can be tabulated or shown in a contour diagram similar to the one illustrated here. In this case, Section C2 is a bottleneck during the peak 15 minutes of the peak hour, while Section C4 is a bottleneck during the entire peak hour and meters traffic to downstream sections, which have relatively consistent operations throughout the peak hour.

LOS is determined for each section Freeway LOS is based on density Density = demand / speed Demand must be adjusted from vehicles per hour to passenger cars per hour to account for the effects of trucks in the traffic stream Supersection generally operates at LOS E or F throughout the peak hour Example Problem 4 illustrates the calculation of freeway LOS, which is based on vehicle density in passenger car equivalents per mile per lane. Density is equal to demand divided by speed, both of which have already been calculated, although demand must be converted from vehicles per hour to passenger car equivalents per hour to account for the effect of trucks in the traffic stream. Once this conversion is made, determing LOS is a straightforward excercise involving one calculation and the use of a lookup table that matches density to LOS. The result confirms the initial screening analysis finding that the supersection operates at LOS E or worse.

Queues are estimated for each section If the queue length exceeds the section length, the section is considered to be 100% in queue Queues are not propagated upstream in the planning method More detailed analysis is required if a section is 100% in queue Example Problem 5 demonstrates queue estimation. All of the information needed to estimate queue length—demand, capacity, and density—have been determined in previous examples. The planning method does not propagate queues upstream; therefore, once the queue length exceeds the section length, the section is considered to be 100% in queue and flagged for more detailed analysis.

Measures of the section’s reliability are estimated Compute vehicle miles traveled (VMT) Compute vehicle hours traveled (VHT) Compute average facility speed = VMT / VHT Identify maximum facility demand-to-capacity ratio Compute the recurring delay rate Estimate the incident delay rate Estimate the mean travel time index Estimate the 95th percentile index Estimate percent trips under 45 mph Example Problem 6 demonstrates the calculation of three measures of facility reliability. All of the input data required in this example have already been provided or calculated in previous examples. The example presents nine steps, each involving either one facilitywide calculation or one calculation per section, for estimating the mean and 95th percentile travel time indices and the percentage of trips through the section with an average speed under 45 mph.

The effect of adding an auxiliary lane to the bottleneck section is evaluated Calculations in Examples 2–5 are repeated Auxiliary lane removes the bottleneck in Section C-4, but sends more demand downstream LOS is F in either scenario, but facility speed, density, queuing, and maximum demand-to-capacity ratio improve with the auxiliary lane Example Problem 7 demonstrates how a potential mitigation option can be evaluated at a planning level, as well as how two scenarios can be compared when both operate at LOS F. In this example, an auxiliary lane is added to the bottleneck section to add capacity. It turns out the lane would address the lack of capacity in Section C-4, but the additional demand that can now be served in this section cannot be entirely served by the next three downstream sections, resulting in an increase in the number of over-capacity sections. The facility as a whole operates at LOS F in either scenario, but facility speed, density, queuing, and maximum demand-to-capacity ratio are substantially improved with the auxiliary lane, indicating overall freeway operations would be improved by the mitigation option. Maximum d/c Ratio by Scenario C-1 C-2 C-3 C-4 C-5 C-6 C-7 Speed (mph) Do Nothing 0.82 1.04 0.94 1.28 0.89 0.96 42.0 Add Lane 0.74 0.97 1.09 0.93 53.6

Section U: Case Study 2—Arterial Bus Rapid Transit
Planning study for a proposed 14-mile BRT line through Oakland, California 110 signalized intersections Demonstrates urban street and multimodal planning methods One travel lane in each direction would be removed to create exclusive bus lanes Case Study 2 provides six example problems that demonstrate how HCM planning techniques can be applied to a multimodal urban street analysis. A 14-mile bus rapid transit project is proposed that would remove one travel lane in each direction to create exclusive bus lanes. The objective of the planning study is to evaluate the effect of the proposed project on automobile, bus, pedestrian, and bicycle operations.

Section U: Case Study 2—Example Problem 1
Facility is split into 10 supersections on the basis of similar demand volumes, speed limit, median presence, and number of lanes LOS D service volume calculated using national default values Available peak hour count data converted to daily volumes Six supersections that would operate worse than LOS D with the project are identified Remaining examples focus on one of these supersections Example Problem 1 demonstrates how the study area is divided into ten supersections on the basis of similar demand volumes, speed limit, median type, and number of lanes. It identifies the required data for the analysis and demonstrates how to identify the maximum service volume for a given LOS. As the agency’s operations standard is LOS E, LOS D is used as the service volume to ensure that all potentially problematic sections are included in the screening. Each supersection’s daily volume is compared to the LOS D service volume, and six supersections are identified where the daily volume would exceed the LOS D service volume with the project in place.

Section U: Case Study 2—Example Problems 2 & 3
Determine left-turn phasing Identify lane groups Develop equivalent through- passenger-car volumes Calculate critical lane group volumes Compute intersection volume-to-capacity ratio The remaining example problems in Case Study 2 focus on one of the six supersections identified as having potential operational problems if one lane is taken away for an exclusive bus lane. Example Problem 2 goes through the process of evaluating the volume-to-capacity ratio of an intersection with protected left-turn phasing (i.e., an intersection where left turns are made during an exclusive phase indicated by a green left-turn arrow). The calculation sequence is presented in detail. The calculations can be performed by hand for a single intersection, but if multiple intersections are to be evaluated, implementing the method in a spreadsheet may be more efficient. Example Problem 3 is similar to Example Problem 2, but evaluates an intersection with permitted left-turn phasing.

Determine intersection approach capacity Determine delay by appoach Determine auto speeds and LOS Determine bus speeds Example Problem 4 demonstrates the calculation of average auto speed and LOS by direction, as well as average bus speeds. An evaluation of intersection approach capacities for the entire six-intersection section finds that one intersection is expected to operate over capacity, while another is expected to operate near capacity. The analysis finds that the exclusive bus lanes will allow buses to travel faster than autos in both directions during the afternoon peak hour. Downstream Intersection 48th 49th 51st Claremont 55th Speed limit, Spl (mph) 30 User adjustment, UserAdj (mph) 5 Segment length, L (ft) 655 468 478 269 798 Running time, tR (s) 12.8 9.1 9.3 5.2 15.6 Control delay, d (s) 18.6 22.7 140.5 7.2 52.7 Volume-to-capacity ratio, X 0.59 0.82 1.20 0.47 0.99 Segment travel time, Tt (s) 31.4 31.8 149.8 12.4 68.3 Segment speed, ST,seg 14.2 10.0 2.2 14.8 8.0 LOS D F

Estimate average and 95th percentile queues by major street approach Identify potential queuing “hot spots” where queues may back into adjacent intersections or block major driveways. Example Problem 5 demonstrates the process of estimating average and 95th percentile queues and interpreting the results. This type of evaluation can be used to identify potential “hot spots” where intersection or driveway blockage may be an issue that will need to be looked at in greater detail.

Evaluation of before-and-after pedestrian, bicycle, and transit LOS Before 7–14 foot sidewalks Two travel lanes and one parking lane each direction 6 local buses per hour After One travel lane, one bus lane, and one 5-foot bicycle lane in each direction Remaining 3 feet used to help create a 5-foot landscape area 5 BRT buses (one stop in section) and 4 local buses per hour Example Problem 6 demonstrates the calculation of pedestrian, bicycle, and transit LOS. As part of the BRT project, modifications will be made to the street to create a more bicycle- and pedestrian-friendly environment. The parking lane will be removed and converted into a bicycle lane and a landscape buffer area. An exclusive bus lane will be created from one of the two travel lanes in each direction. Overall bus service through the corridor will increase, although most stops will actually see a decrease in service, with the number of buses per hour dropping from 6 to 4. The one stop in the section that will be served by the new BRT route will have 9 buses per hour, up from the current 6.

Pedestrian LOS improves from mostly LOS B to LOS A Greater separation from most of the motorized traffic (bus lane and buffer area) improves the LOS Bicycle LOS improves from mostly LOS E to LOS A Bicycle lane, plus low volumes in the adjacent bus lane greatly improves the LOS Bus LOS stays at LOS C at local stops Less-frequent service offset by improved bus speeds Bus LOS improves to LOS B at BRT stop Improved frequency and speed improves the LOS The results of the analysis shows that the proposed project improves service quality for the pedestrian and bicycle modes, and maintains or improves overall bus LOS. The next stage of the planning process would then need to look at the potential trade-offs needed at the intersections where insufficient motorized vehicle capacity would be provided under the initial plan.

Section V: Case Study 3—Long-Range Transportation Plan
Developing free-flow speeds and roadway capacities for transportation model input HCM-based volume‒delay functions Predicting density, queues, and delay Predicting reliability Case Study 3 provides four example problems that demonstrate how HCM planning techniques can be applied to develop improved inputs to regional travel demand models and how they can be used to post-process model outputs to generate additional useful performance measures.

Section V: Case Study 3—Example Problem 1
Create categoriza- tion scheme for lookup table Functional class Land use Terrain Ramps Identify free-flow speed Identify capacity Facility Type Area Type Free-Flow Speed (mph) Capacity (veh/ln) Freeway Downtown 55 1,800 Urban 60 Suburban 65 1,900 Rural 70 Principal Highway Rural Multilane 1,700 Rural Two-lane 1,300 Minor Highway 45 1,500 Arterial 25 700 35 600 Collector 30 Example Problem 1 shows how an analyst can develop a lookup table that provides an HCM-based free-flow speed and capacity for different combinations of facility type and other factors of interest (e.g., area type, terrain, specialized facility types). Each link in the travel demand model is then assigned a free-flow speed and capacity from the lookup table on the basis of the link’s particular combination of chararacterstics.

Section V: Case Study 3—Example Problem 2
Develop speed–flow curve calibration (A and B) parameters by facility type Determine a link’s demand-to-capacity ratio Apply the appropriate speed–flow curve for the link to estimate average speed Example Problem 2 shows how HCM-based speed–flow curves can be developed and incorporated into a regional travel demand model. This process can also be used to post-process model output, when more accurate speed estimates are desired as inputs into air quality and noise models. Link ID Facility Type Lanes Demand (veh/h) Capacity (veh/h) Free-Flow Speed (mph) BPR A BPR B d/c Ratio Speed (mph) A001 Urban freeway 4 8,220 7,200 60 0.17 7 1.14 42.0 A002 Urban arterial 3 1,740 2,100 35 2.19 2 0.83 14.0 A003 Urban collector 1,170 1,200 30 1.89 0.98 10.9 A004 Rural freeway 2,790 3,800 70 0.31 0.73 67.6 A005 Rural principal highway 1,490 3,400 55 0.18 8 0.44 55.0 A006 Rural minor highway 1 250 1,300 45 0.38 9 0.19 45.0

Section V: Case Study 3—Example Problems 3 & 4
Link density and (for freeways) link LOS Vehicle-hours in queue by link Vehicle hours of delay by link Average annual travel time index by link Systemwide average annual travel time index 95th percentile TTI Percent of trips under 45 mph Example Problems 3 & 4 demonstrate how travel demand model output can be post-processed to generate additional useful measures of operational performance. Example Problem 3 demonstrates the calculation of density, queueing, and delay, while Example Problem 4 demonstrates the calculation of measures of travel time reliability.

Freeway master planning Urban street and multimodal analysis
Questions Freeway master planning Urban street and multimodal analysis Long-range transportation planning Questions on these topics? This concludes the overview of the three case studies provided in the Guide. I will now take the remaining time to answer questions on the case studies, as well as answer questions on earlier portions of the web briefing. 74

HCM – Sixth Edition Introducing the Planning & Preliminary Engineering Applications Guide to the HCM Today’s web briefing introduces the Planning & Preliminary.

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HCM – Sixth Edition Introducing the Planning & Preliminary Engineering Applications Guide to the HCM Today’s web briefing introduces the Planning & Preliminary.

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