Abstract
The Lassen County Transportation Commission (LCTC) is evaluating safety improvements to the United States Route 395 within Lassen County to enhance mobility, safety, and promote economic activity in the adjoining areas. The main proposal is to expand United States Route 395 corridor from a two-lane conventional highway to a four-lane divided expressway, from Hallelujah Junction (interchange with State Route 70) to the State Route 36 intersection near Susanville. The purpose of this study was to conduct a detailed safety analysis of the current roadway conditions in the corridor and evaluate the safety impact of the corridor expansion in the future. The safety analysis divided the highway within study limits into four segments and evaluated the crash rate of each segment. The crash rate was ultimately used to prioritize segments for potential future safety improvement projects. The safety analysis also utilized the state-of-the-art methods from the American Association of State Highway and Transportation Officials (AASHTO) Highway Safety Manual (HSM) to compare the safety of a “no build” scenario versus corridor expansion. Three sets of data were required to perform above mentioned analyses which included traffic volume, crash history, and highway geometry data which were collected from various state and federal agencies as well as academic institutions. The results of the analyses were ultimately utilized to provide multiple recommendations which include identifying the priority segments as well as future engineering studies needed to finalize the decision-making process.