Ask the Experts–Implementing the Systemic Approach to Safety
What is the systemic approach to safety?
The systemic approach to safety involves identifying improvements that are widely implemented based on high-risk roadway features correlated with particular severe crash types. The approach helps states align their efforts with the requirements for the highway safety improvement program (HSIP), which focuses on fatal and serious injury crashes on ALL public roads. A significant number of crashes occur on rural roads, which are often part of the local system. Because there is no even distribution of these crashes across the many miles of rural roadways, it is often difficult to isolate high-crash locations. The systemic approach gives states a way to make these investments in a cost-effective, efficient way. The Moving Ahead for Progress in the 21st Century (MAP-21) explicitly defines safety and the law clarifies the eligibility of systemic projects for HSIP funding.
Systemic starts with a different premise for identifying potential for safety improvements, leading to a different set of projects. The systemic approach looks at crash history on an aggregate basis to identify high-risk roadway characteristics (e.g., sharp curves combined with higher traffic volumes, or sharp curves and narrow shoulders). While the traditional site analysis approach results in safety investments at specific locations, the systemic approach leads to widespread implementation of projects to reduce the potential for severe crashes, whether or not crashes have occurred at any given site. Because many severe crashes are spread out over a wide area, the systemic approach provides state, regional, and local agencies with an alternative method to identify and implement low-cost safety countermeasures addressing specific risk factors across the transportation network. Systemic analysis is a complement to site-specific analysis, and can be very effective in implementing low-cost safety countermeasures.
A step-by-step process for conducting systemic safety analysis; a mechanism for quantifying the benefits of safety improvements implemented through a systemic approach; and analytical techniques for determining a reasonable balance between the implementation of safety treatments at high-crash locations (black spots) and systemic safety improvements is being developed. As part of the project, consultants worked with the Federal Highway Administration (FHWA) to create a web site that includes additional information on the process as well several examples of how states have used the process. The web site is located at http://safety.fhwa.dot.gov/systemic/.
Beth Wemple, a Senior Associate at Cambridge Systematics, brings a wealth of road safety research and transportation policy and planning experience along with traffic engineering skills. She is a member of, and the Secretary to, the Transportation Research Board Highway Safety Performance Committee, which guided the research for the first edition Highway Safety Manual. She is leading the Systemic Safety Project on behalf of FHWA. The project has three major goals: 1) a step-by-step process for conducting systemic safety analysis; 2) a mechanism for quantifying the benefits of safety improvements implemented through a systemic approach; and 3) analytical techniques for determining a reasonable balance between the implementation of safety treatments at high-crash locations (black spots) and systemic safety improvements.