Projects

Highway Safety Improvement Program (HSIP) Evaluation

Description:
The objective of this research was to provide support to the Wisconsin Department of Transportation (WisDOT) in evaluating Highway Safety Improvement Program (HSIP) projects implemented in Wisconsin.  State-of-the-art analysis techniques such as Empirical Bayes analysis was used to conduct evaluation of HSIP projects and quantify safety improvements at individual project locations.  Benefit-cost ratio calculations were also conducted based on Empirical Bayes estimates and naïve Before-After analysis. 

A list of projects completed in the state of Wisconsin in the SFY 2003, 2004, 2005, and 2006 was collected from the FIIPS database and evaluated.  According to the project locations and scheduled start and completion dates, the TOPS Laboratory developed a process to extract appropriate crashes (by location, type and year) from the WisDOT crash database for a before-and-after project-level analysis.  A significant amount of crash data, 5 years of “before” and 3 years of “after” data, was retrieved to justify the use of HSIP funds.  TOPS Laboratory used the Before-After and Empirical Bayes evaluation methods to assess the HSIP projects from various aspects.  Fatal and injury crashes were the focus but the analysis was extended to target crashes based on the nature of the projects.  Moreover, a Benefit-Cost ratio analysis was also performed to provide an economic perspective to the evaluation based on both the Before-After and Empirical Bayes analyses.

Projects evaluated consisted of safety improvements on highways and rail road crossings based on available crash data.  The projects crossed a wide spectrum of highway safety improvements and enhancements, such as lane reconfiguration, traffic signal enhancements, and addition of turning lanes, pavement friction improvement, and so on.  Each project evaluated includes a general description of the project location, the safety issues experienced at that location, the improvements that were implemented, the Before-After and Empirical Bayes crash analysis and respective Benefit-Cost analyses based on Before-After and Empirical Bayes results.

Documents:

Document Name	Files	Date Posted
Wisconsin Highway Safety Improvement Program (HSIP) Evaluation - Year One Support	Final Report (PDF, 4.51 MB)	10/26/2009
Wisconsin Highway Safety Improvement Program (HSIP) Evaluation - Year Two Support	Final Report (PDF, 2.17 MB)	10/26/2009
Wisconsin Highway Safety Improvement Program (HSIP) Evaluation - Year Three Support	Final Report (PDF, 280 KB)	10/26/2009
Wisconsin Highway Safety Improvement Program (HSIP) Evaluation - Year Four Support	Final Report (PDF, 7.03 MB)	10/26/2009