2017 Research Project

An Enhanced Systemic Approach to Safety

Principal Investigator
Offer Grembek
University of California, Berkeley
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Libby Thomas
University of North Carolina, Chapel Hill
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To date, the dominant approach used by state agencies to allocate safety resources is the hotspot approach, which focuses on identifying and recommending improvements for high collision concentration locations. Another approach is the systemic approach that seeks blanket improvements that can be implemented at sites across the road network, based on specific roadway features that are associated with a particular crash type. While the hotspot approach is reactive in the sense that it focuses exclusively on sites that already had crashes, the systemic approach has both reactive and proactive components to it. The systemic approach is reactive since it uses historical crash data to identify the type of roadways that suffer from recurring safety concerns, and it is proactive in the sense that it provides a mechanism to make improvements at sites that share the same design and operational attributes, but have not had many (or any) crashes yet. The systemic approach is typically used in parallel to the hotspot approach and is considered a complement rather than an alternative.

This study will develop a prototype tool for conducting a systemic safety analysis for a scalable area. At the core of the proposed approach is a transparent systemic crash matrix that shows what types of crashes occur on what types of facilities. The different rows in the systemic matrix represent different crash types, while the columns represent different facility types. The cells of the matrix are referred to as crash profiles and include the number of crashes that occurred for each crash profile. This method provides an agency with a simple-to-assemble, simple-to-interpret snapshot of any systemic problems on their network or study area.

The anticipated outcomes of the study area prototype tool for conducting a systemic safety analysis that can be conducted simultaneously for all modes of traffic, along with a set of possible engineering and non-engineering countermeasures; and a systemic tool that can provide agencies with the ability to make systemic data-driven blanket improvements across a desired area to support system-wide safety improvement.

Project Details

Project Type: Research
Project Status: Active
Start Date: 3-1-2017
End Date: 7-31-2018
Contract Year: Year 1
Total Funding from CSCRS: $120,000
Co-sponsors:  California Department of Transportation
Collaborating Organizations: University of California, Berkeley; University of North Carolina, Chapel Hill