CHAPTER 1

Introduction and Background

Background

Visualization methods have long been integral to the public involvement process for transportation planning and project development. From well-established methods (e.g., conceptual sketches or photo simulations) to the latest immersive technologies, state DOTs recognize that visualization can “significantly increase public understanding of a project’s appearance and physical impacts compared to text or conventional engineering drawings” (FHWA 2020). Emerging methods, such as interactive three-dimensional (3D) environments and virtual reality (VR) and augmented reality (AR), provide viewers with an experiential dimension that can dramatically enhance public understanding of transportation options and design concepts (AASHTO 2020).

Despite the transformative potential of newer visualization methods for public involvement, state DOT adoption has been uneven. This synthesis study arose from the need to better understand the current state of the practice, including the methods in use for various phases of project development, the methods agencies use to present visualizations to the public and gather feedback, DOTs’ strategies for providing accessible and equitable engagement with these methods, and common barriers to innovation. Through a literature review, a survey of state DOTs, and in-depth interviews with representatives of selected DOTs, the synthesis study team examined each of these topics to develop a current snapshot of state DOT practice.

Objective and Method

The objective of this synthesis was to document state DOT practices of visualization for public involvement throughout the life cycle of plans, programs, and projects. The synthesis report provides

• A review of the existing literature.
• The results of an online survey sent to all state DOTs and the District of Columbia DOT.
• In-depth interviews with current practitioners at select state DOTs documenting tools, methods, techniques, trends, and challenges.

This synthesis report primarily focuses on documenting the type and implementation of visualization methods used in transportation project public involvement; however, institutional and organizational policies and practices, as they affect implementation, are also described.

The information collected in preparing this synthesis report included the following:

• Publications describing use of visualization in transportation public involvement.
• Survey data on state DOT visualization practices, including methods in use and their implementation.
• Knowledge gaps and the need for additional research.

The literature review was designed to obtain information on current knowledge, practices, and relevant research pertaining to the synthesis topic and included collection, evaluation, and review of publications that related to the study questions. Limited publications on this topic within the past 10 years were found, and questions of what is known and not known about this topic were answered primarily through the survey and in-depth interviews.

The survey was sent to 50 state DOTs and the District of Columbia DOT. The distribution list focused on agency practitioners in communications, public involvement, and public relations. Several DOTs provided an alternate contact for the online survey in response to initial contact—not all these alternate contacts were communication practitioners.

An online survey link was sent to one recipient at each state DOT and the District of Columbia DOT. The survey questions were reviewed, tested, and approved by NCHRP.

For this synthesis report, the 13 visualization methods (along with the icon assigned to each) are as follows:

Conceptual sketches: simple but complete sketches of key aspects of a system.
Infographics: visual presentations of information with minimal text to make a topic easily understandable.
Videos: visual media products with moving imagery and optional audio or music.
Drone imagery: aerial imagery captured by an unmanned device.
360-degree panoramic images: interactive images with unobstructed views in all directions from a focal point.
Photo simulations: photographic images enhanced to simulate a design concept (e.g., before/after).
Animated graphics/motion graphics: animation of visual elements.
3D static rendering: a two-dimensional (2D) image produced from a 3D model.
3D animation: a movie clip in which objects and characters are placed in a 3D space and manipulated to create the illusion of motion.
4D sequential rendering: a 3D model connected to a schedule to simulate various stages of construction.
Real-time interactive 3D: a 3D model in which the viewer can navigate and interact with the built environment.
Augmented reality: superimposed computer-generated image on a user’s view of the real world.
Virtual reality immersive: computer-generated simulation of a 3D image or environment viewed using a head-mounted immersive display or web interface or other interactive display.

A response rate of 76% (39 DOTs) was achieved after four separate rounds of follow-up with the DOTs, which included outreach to additional DOT contacts provided during follow-ups.

As a follow-up to the survey, four state DOTs were contacted by telephone to provide additional insights on their use of visualization, including the following:

• Types, formats, and implementation of visualization technologies in public involvement.
• Strategies for providing accessibility and equitable engagement with visualization products.
• DOT guidelines and policies for use of visualization.
• Barriers to using innovative visualization techniques.

Institutional and organizational issues affecting the use of visualization for public involvement were not fully explored in this synthesis study, but the in-depth interviews with select DOTs revealed that these issues are influential factors in visualization procurement, method, and implementation.

Organization

Following Chapter 1, Chapter 2 summarizes the body of literature found about visualization for public involvement. (The synthesis report authors found few publications from the last 10 years, with most content produced by the FHWA Every Day Counts [EDC] program or found in state DOT guidelines for public involvement. Other information was delivered through webinars highlighting effective practices and case examples of transportation projects using visualization for public involvement, rather than in formal publications.)

Chapter 3 provides a summary of responses by state DOTs to the 10 questions in the online survey. Complete, aggregated survey responses are provided in Appendix B.

Chapter 4 summarizes the in-depth interviews with four state DOTs. Visualization examples of different methods are interspersed throughout.

Chapter 5 documents effective visualization methods, implementation, and practices; challenges and barriers to broader use of visualization, especially advanced methods; and suggested topics for future research that could advance the use of visualization more broadly.

A glossary, a list of abbreviations, and a References section are included to enhance understanding of chapter content. Appendix A contains the survey instrument. Appendix B presents the aggregated survey responses, and Appendix C provides the case example interview outline. Appendix D contains source links for some of the DOT-provided visualization examples included in the DOT interview writeups (Chapter 4).