Jeya Padmanaban, Ravishankar Rajaraman, Greg Stadter, Swastik Narayan, Bharat Ramesh

• The National Highways Development Project in India is aimed at upgrading over 12,000 km of national highways from 2-lane undivided roads to 4-lane divided roads. With nearly 40% of fatal crashes being reported on national highways, the effect of this project on road safety needs to be assessed. Researchers carried out on-site crash investigations and in-depth crash data collection for a period of 45 to 60 days on four 2-lane undivided highways and a 4-lane divided highway. Based on 76 crashes examined, researchers found a shift of crash pattern from head-on collisions on undivided 2- lane highways to front-rear collisions on divided 4-lane highways. This paper presents the methodology, analysis of crashes examined, and the critical safety problems identified for greater consideration in future highway development projects. This paper also highlights the need and significance of in-depth crash investigations to understand local traffic conditions and problems in India.