California Partners for Advanced Transportation Technology

This report describes the research work that was conducted to improve the effectiveness and consistency of methods for identifying High-Concentration Collision Locations (HHCL) within the California State Highway System that have collision frequencies significantly greater than expected when compared to other locations. The accuracy and reliability of HCCL reports are critical as the outcome of the screening process is the basis for follow-up field investigation as well as potential safety improvements.During the course of the project, the research team from the Traffic Safety Center (TSC) and California Partners for Advanced Transit and Highways (PATH) of University of California at Berkeley conducted extensive literature reviews and surveys, and interacted with a number of out-of-state agencies and experts to gather the latest information and techniques regarding HCCL. The primary findings and conclusions are summarized in the report with recommendations for potentially addressing and improving the process of identifying HCCL.