U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
This edition of the Traffic Monitoring Guide (TMG) is intended to provide the most up to date guidance to State highway agencies in the policies, standards, procedures, and equipment typically used in a traffic monitoring program. The TMG presents recommendations to help improve and advance current programs with a view towards the future of traffic monitoring and with consideration for recent transportation legislation resulting from MAP-21. The needs for traffic data at both the Federal and State levels will continue to require that States have a well-designed traffic monitoring program to support all business areas. Traffic data and information is needed to assess current and past performance and to predict future performance. Improved traffic data, including data on ramps, is needed for reporting in the Highway Performance Monitoring System (HPMS) and there are now opportunities to utilize traffic data from Intelligent Transportation Systems (ITS) to support coordination of planning and operations functions at the Federal and State levels.
Improvements in traffic data collection technology since the publication of the TMG in 2001, has allowed States to improve their data collection processes and to streamline QA/QC procedures, thereby replacing manual procedures with new automated ones. New technology also now enables States to collect data on non-motorized travel including bicycle and pedestrian traffic. This new capability is addressed in more detail in Chapter 4. The use of non-motorized travel data and information supports analysis regarding the impact to the transportation network (from a volume and safety perspective), resulting from the use of bicycles as an alternative method for travel compared to the traditional motor vehicle. The new technologies and procedures for traffic monitoring presented in this Guide are supplemented (in the appendices) with practical examples from actual State experiences in improving traffic monitoring programs.
The guidance presented in the TMG should be used to help States manage and improve their traffic monitoring programs, with consideration for overall business needs for traffic data and information. Chapter 2 explains the importance of having a well-designed traffic monitoring program to support typical business needs. This Guide is written to assist both experienced traffic data collection personnel and those who are less-experienced, or who are new to traffic data collection. Quick references to topics are available in the Index and may also be found in the Table of Contents. Other reference material that may benefit traffic data collection personnel and traffic program managers is found in Appendix M, References.
This edition of the TMG also includes new data formats as an option for reporting traffic data. These new formats are known as the Per Vehicle Formats for reporting volume, speed, vehicle classification, and vehicle weight data. Data formats are also provided for reporting non-motorized data for those States with capabilities to collect this type of data. This edition of the TMG has been developed with considerable input from State traffic data program managers and the vendors who design and build traffic data collection equipment. This approach has resulted in a guidance document that FHWA anticipates will continue to be beneficial to States in improving their business processes, technology, and equipment used to successfully manage their traffic monitoring programs.
The scope of State traffic monitoring programs has grown over the last decade to now include the capability to collect speed data, which is critical for analysis in supporting State highway safety programs. While the collection of volume, classification, and weight data continues to be the foundation of a State’s traffic monitoring program, the addition of speed data greatly enhances the capabilities of the traffic programs to meet additional business needs, particularly in the area of improving performance measures related to safety. New requirements for performance monitoring based on MAP-21 legislation will also be supported by the guidance presented in this Guide. Traffic data from the States continues to be required to meet the reporting requirements of the Federal Highway Administration (FHWA) under United States Code of Federal Regulations (CFR) title 23, 420.105(b), which requires States to provide data that supports FHWA’s reporting responsibilities to Congress and to the public. Traffic data reported under this Federal regulation is submitted as part of the annual Highway Performance Monitoring System (HPMS) report from each State.
Traffic data is typically used to support highway agency activities including design, maintenance, operations, safety, environmental analysis, finance, engineering economics, and performance management. Each State has its own traffic data collection needs, priorities, budgets, geographic and organization constraints. These differences cause agencies to select different equipment for data collection, use different data collection plans, and emphasize different data reporting outputs. This Guide is intended to provide guidance to highway agencies in some of the successful approaches in data collection, analysis, and reporting based on best practice examples, which are highlighted in the appendices.
The organization of the material presented in this Guide begins with explaining the theory, technology, and concepts typically used in a traffic monitoring program (Chapter 1). The Guide also highlights the business needs for traffic monitoring programs (Chapter 2) and provides comprehensive guidance on the methodologies used for motorized (Chapter 3) and non-motorized traffic monitoring practices (Chapter 4). The importance of traffic data in supporting transportation management and operations activities is also discussed in Chapter 5, with HPMS reporting requirements for traffic data explained in Chapter 6. The final chapter (Chapter 7) defines the record formats used for submitting traffic data for both motorized and non-motorized data, along with a table explaining the deadlines for submitting traffic data to the FHWA Office of Highway Policy Information.
Several appendices are also included as part of the Guide to provide a glossary of terms, list of acronyms, Frequently Asked Questions (FAQs), and best practice examples from States and the private sector in designing statewide traffic monitoring programs, establishing data QA/QC criteria, and setting up and calibrating data collection equipment. Other appendices include guidance on the use of traffic data for pavement design purposes, guidance on length-based classification, and the QC checks performed on the traffic data by the Travel Monitoring Analysis System (TMAS) software. This Guide also includes an appendix of References and an Index for quick location of a particular topic related to traffic monitoring.
The chapters and appendices in this Guide include the following:
Chapter 1 – Traffic Monitoring Theory, Technology, and Concepts – This chapter discusses the terminologies used in traffic monitoring and defines the types of traffic counts conducted (i.e., continuous, short duration), explains factor computations, and defines data products derived from the collection of traffic data.
Chapter 2 – Traffic Monitoring Program – Business Planning and Design – This chapter explains how data business planning can be used to support and improve the design of a traffic monitoring program in accordance with the Code of Federal Regulations.
Chapter 3 – Traffic Monitoring Methodologies – This chapter is the most comprehensive chapter in the TMG. It provides guidance on the following:
Chapter 4 – Traffic Monitoring for Non-Motorized Traffic – This chapter provides basic guidance on non-motorized traffic volume monitoring. The term non-motorized pertains to bicycles, pedestrians, and other non-motorized road and trail users. The chapter highlights the challenges in collecting non-motorized data compared with traditional collection of motorized traffic data. It also provides several examples of the types of data collection equipment available and describes procedures that can be used to collect this type of data.
Chapter 5 – Transportation Management and Operations – This chapter provides guidance and examples on coordinating activities for transportation management and operations functions within State DOTs. The specific types of functions covered include:
Chapter 6 – HPMS Requirements for Traffic Data – This chapter provides guidance to State DOTs in meeting the reporting requirements for the Highway Performance Monitoring System (HPMS). Traffic data represents a significant portion (25%) of the HPMS data reported to FHWA annually. Much of this data is provided from a State’s traffic monitoring program. The traffic data items reported in HPMS are identified and the uses of this data are also explained in this chapter.
Chapter 7 – Traffic Monitoring Formats – This chapter defines the data record formats and data submittal frequency to be used for reporting volume, speed, vehicle classification, and weight data for motorized data and also describes the data formats for reporting non-motorized data. It includes new formats now available, known as Per Vehicle Formats, as an alternative method for submitting traffic data to FHWA. The traffic data formats described in this chapter are in addition to the traffic data which is required to be submitted annually to FHWA as part of the HPMS submittal.
Appendices: There are also several appendices included in the TMG to provide additional guidance to the user. Of particular significance, this edition of the TMG includes best practice examples in traffic monitoring in appendices D, E, F, and L.
The appendices in the TMG include the following:
Appendix A – Glossary of Terms
Appendix B – Acronyms
Appendix C –Vehicle Types
Appendix D – Compendium of Designing Statewide Traffic Monitoring
Appendix E – Compendium of Data Quality Control Criteria
Appendix F – Compendium of Equipment Calibration Procedures, Current Practices, and New Procedures
Appendix G – North Carolina Department of Transportation Clustering Methodology for NC Traffic Data Inputs for MEPDG
Appendix H – Traffic Data for Pavement Design
Appendix I – Frequently Asked Questions (FAQs)
Appendix J – TMAS 2.0 QC Checks
Appendix K – Length Based Class Memo
Appendix L – Additional State Traffic Monitoring Program Examples
Appendix M – References
Appendix N – An Index is also included in the TMG to assist users with quickly locating information on a particular topic
