Incident Characteristics and Impact on Freeway Traffic

Transportation management centers (TMCs) generate and archive enormous amounts of data. Many applications of archived intelligent transportation system (ITS) data nationwide, including Texas, address transportation planning needs. As the number of applications of archived ITS data increases, interest is growing in identifying areas where archived ITS data could result in more effective TMC operations. One area of interest is how to use archived ITS data to help improve incident management practices. Using geographic information system (GIS), traffic engineering, and statistical analysis techniques, this report describes procedures to determine patterns in the spatial and temporal distribution of incidents along freeway corridors. The report describes current incident detection and data archival at several Texas TMCs, a process to develop a data model and geodatabase of ITS equipment and archived ITS data using a variety of data sources at TransGuide, a process to determine patterns in the spatial and temporal distribution of freeway incidents in San Antonio, a procedure to calculate the impact of incidents on traffic conditions, and recommendations for implementation of the research findings.