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Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations

This report is an archived publication and may contain dated technical, contact, and link information
Publication Number: FHWA-HRT-10-073
Date: November 2010

Roadway Geometry and Inventory Trade Study for IntelliDriveSM Applications Applications



The U.S. DOT IntelliDrive initiative seeks to improve transportation safety and mobility while reducing the environmental impact of surface transportation through the use of networked wireless communication among vehicles, infrastructure, and travelers' personal communication devices.

Many potential IntelliDrive applications require accurate positioning and temporally current information on roadway geometry and specific roadway features, including curve locations, locations of signalized or signed intersections, number and width of travel lanes, presence and length of auxiliary turn lanes, roadway shoulder and median characteristics, posted speed limits, etc. Some of these data are available in geospatial road databases created by government transportation agencies or commercial database developers, but there is currently no single data source that can provide all of the required data on a consistent, nationwide basis at the appropriate levels of positional and temporal accuracy.

The purpose of this study is to investigate existing and emerging sources of roadway geometry and inventory data, including both commercial and public databases, as well as technologies and methods for collecting roadway data items. These data sources are evaluated relative to potential near-term (within the next 5 years) IntelliDrive application data needs that were proposed and vetted through representative stakeholder groups. The study also examines the workflow practices and business models of current data providers and their capacity for delivering the roadway geometry and inventory data needed for future IntelliDrive applications.


This report summarizes the approach, findings, and recommendations from the roadway geometry and inventory trade study. The report is composed of six chapters.

Chapter 2 describes the approach taken by the study team to propose an initial list of roadway data items, vet the list among potential IntelliDrive stakeholders, and develop a final list based on stakeholder feedback for use in evaluating current and emerging data sources.

Chapter 3 summarizes the findings from interviews with roadway geometry and inventory data sources. These sources include commercial roadway database developers; Federal, State, and local transportation agencies that collect and maintain roadway inventory data; transit operating agencies; and commercial roadway data collection firms that are using innovative technologies to collect and process roadway geometry data.

Chapter 4 compares each of the road data items developed in chapter 2 against the roadway data that are currently being collected by commercial and public sources in order to provide a clear picture of specific data gaps.

Chapter 5 analyzes and compares roadway geometry and inventory data sources based on the technical characteristics of each database and on the operational and business practices of each data provider. Key challenges and obstacles to providing data to meet potential near-term IntelliDrive needs are discussed.

Chapter 6 discusses potential options for addressing the data gaps and challenges identified in the previous chapters. Options include alternative institutional structures for database development and maintenance, Federal regulatory and funding strategies, and promising research initiatives.

Three appendices are included to provide additional detail on specific aspects of the trade study. These appendices include: (1) a list of IntelliDrive stakeholders who participated in the identification of roadway data items, (2) a summary of stakeholder comments regarding potential data items needed for IntelliDrive applications, and (3) profiles and summaries of commercial roadway database developers; Federal, State, and local roadway agencies; and firms using innovative roadway data collection technologies that were interviewed in the course of this study.

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