Visualization is a useful tool in communicating CMP information, but there is no single visualization approach that is applicable in all MPOs - the best approach will vary for each MPO, based on the data and resources available, the goals and objectives of the CMP and the MPO in general, and the intended audience. For example, in areas with relatively low congestion, providing visuals that focus on non-recurring congestion may be more appropriate than those focused on recurring congestion. In an area where detailed and extensive data sets are available, it may be preferable to focus on generating detailed, data-driven visuals of observed conditions. Some MPOs use visualizations for internal analytical purposes, while others primarily develop visualizations for use by the public or elected officials. The final visualization approach followed by an MPO should be one that meets its own unique needs.
The effectiveness of CMPs and the use of visualizations is interdependent with the data sources available to MPOs. Newer and improved data sources can enable representations of congestion to be displayed as people experience it - over space and over time - helping to improve citizens’ understanding and acceptance of recommended strategies for improvement.
One important lesson learned with regard to visualization of the CMP is that visualizations intended for public consumption must be easy to understand and must clearly convey their intended message. Graphics should not be littered with superfluous information and should not attempt to show too much information all at once. At the same time, overly simplistic representations of the data may skip over or trivialize important interrelationships that need to be better understood to effectively select and gain support for implementing a particular congestion management strategy.
Several recent innovations appear to have useful application as CMP visualization tools. Several MPOs have begun using online mapping programs to present information in a way that is easier for the public to access and to interact with. Using a program such as this allows a person to view information at multiple scales, to delve into detailed information of interest to them, and to change the display properties to suit their interests (by doing things such as turning layers on and off). Additionally, animations and simulations are beginning to be used as a tool for visualizing congestion in some areas; there has been relatively little CMP-related activity using this tool so far, but it is an area that is ripe for future development.
Animations can be a useful adjunct tool because the nature of congestion is that it varies over time and space, and techniques such as animations that capture and "play-back" such concurrent observed variability in congestion patterns can greatly facilitate understanding of the nature of the problem that needs to be addressed. A drawback of this approach is that animations do not easily lend themselves being put into a static report. The electronic files needed to visualize the data in that manner can be large, which is a challenge to their dissemination and use by the appropriate audiences. However, the increasing competence of the public, officials, and their direct staff in the use of computers for communicating and sharing information and files may make this less of a concern in the future.
The increasing availability of new and improved sources of data on system performance is an important element in the implementation and improvement of CMPs over time. However, it is equally if not more important to ensure that available data is presented in a way that is useful and understandable, allowing informed decision making by MPO professional staff, decision makers, and the public.
Visualization can play a major role in organizing the spatial and temporal data collected as part of the CMP and in communicating the results of the CMP analysis to the public and elected officials. The primary goal of the CMP is for the congestion analysis to be a major factor in the development of long-range plans and short-range funding programs developed by MPOs, and to influence the selection of projects and management and operations strategies that are included in these plans and programs. For this to happen, it is vital for the congestion data collected and analyzed through the CMP to be distributed in a format that can exert that influence on the rest of the MPO planning process. Visualization is a very effective way of doing this.