Safety Assessment of Two-Lane Highway using a Combined Proactive and Reactive Approach: Case Study from Indian National Highways

In India, approximately 30% of road accident fatalities occur on two-lane rural roads. Thus research focused on identifying risk factors on this road type is of immense interest to most of the road agencies. Although these highways are more hazardous and account for more severe crashes, there is a lack of scientific safety assessment of such highways compared with multi-lane highways. Proactive approaches, such as road safety audit, have been widely adopted by the government of India to reduce crash frequency and severity on highways. However, an effective road safety management program should exercise an optimal balance between reactive and proactive strategies to identify potential hazards and treat already existing hazardous sites. Through a case study on two two-lane highways, several risk factors were identified using the principles of road safety audit, and were mapped with the available crash data analysis to develop a risk matrix. This risk matrix was found to be helpful in the selection of countermeasure design in a more scientific way, targeting the frequent crash types and severities expected to result at the high crash sites. Finally, it was observed that integrating the findings from reactive analysis with proactive safety management is more beneficial, since they are methodically proven with historical crash records and provide the knowledge of plausible safety hazards at sites where similar features exist. The proposed methodology could be adopted by road agencies in India and other developing countries for effective proactive safety planning.