Investigation of Freeway Incident Characteristics and Their Influence in Planning an Incident Management Program

Nonrecurrent congestion caused by highway incidents is a major concern for transportation agencies and millions of road users in most metropolitan areas in the United States. Incidents account for 60 percent of congestion-induced delay. As a low-cost approach to incident management, freeway service patrol programs have gained wide popularity. However, information on freeway incident characteristics is limited. In the current paper, incident data recorded by the Hoosier Helper program in north-west Indiana is analyzed. The distributions of incident frequency and clearance time by incident type and lateral location are reported. The variation of incident rate with time of the day is examined, and the influence of various factors affecting the frequency and clearance time of incidents is explored. Recommendations are made to improve the freeway service patrol program, based on the incident data analyzed. The information provided in this study may be useful for planning similar patrol programs in other metropolitan areas in Indiana and other states.