Highway Safety Challenges in India: Understanding road crash patterns and way forward

Twitter

The Global Status of Road Safety report (GSRRS, 2023) by the World Health Organisation has reported a reduction in road traffic deaths globally. There were an estimated 1.19 million road traffic deaths in 2021 – a 5% drop when compared to the 1.25 million deaths in 2010.  However, RTIs have continued to increase in India, with 1,68,491 deaths reported in 2022, an increase of 9% from 2021 (MoRTH, 2023). Thirty six percent of these fatalities were reported on National Highways (NH), 24% on State Highways (SH) and 39% on other roads. The proportion of RTC on NH, SH and other roads have remained unchanged since the road network in India was 63.32 lakh km in March 2019.

The Government of India (GoI) launched a major programme in 2000 to expand and improve highways in India. The major initiatives by GoI include upgradation and strengthening of National Highways through various phases of the National Highways Development Project (NHDP). In addition to other schemes and projects, the initiative is forwarded through the umbrella program of Bharatmala Pariyojana Phase-I.   Seventy thousand kilometres of National Highways (NH) are maintained by NHAI. Through the National Highway Development Programme (NHDP), NHAI is also upgrading nearly 49,000 km of NH. Twenty-four thousand km of highways have been upgraded. Upgradation includes increasing the number of lanes (e.g., from four to six), converting undivided roads to divided highways, and adding paved shoulders to 2 lane roads. The major motivation behind highway upgradation has been improving inter-city and interstate connectivity through capacity enhancement.

Nearly 60% of fatalities occur on highways which constitute 5% of the road length. It is unfortunate that with the expansion of highways, the number of road crashes continue to increase, both in absolute numbers as well as fatalities per 100,000 populations – from 2.1 in 1970 to 12.1 in 2022.

Historical trends from many countries show that despite the increase of vehicles, incomes and population, road traffic injuries (RTIs) have reduced. These countries have important lessons for making Indian highways safe for all road users.

History Lessons

Hagenzieker et. al. (2014) studied the history of road safety and summarised various actions as shown in Table1. Road Safety history is divided into five periods. 

Table 1 Time Periods and their characteristic Road Safety Paradigm (OECD, 1997)

In the early periods, the emphasis on the road user behaviour and corrective measures focused on improving behaviour through education, training and strict penalties. As the RTF trend in figure 3 shows, the RTF rates continue to increase in this period. By the 1960s, focus shifted from blaming individuals to accepting RTIs as a public health problem. It was understood that injuries are produced by energy interchange and in principle etiologically similar to any other disease (Gibson, 1964, Haddon 1968). The understanding that traffic injuries result from a complex interaction of sociological, psychological, physical and technological phenomena resulted in the design of safer products, environments, roads and traffic management systems. Once it was accepted that RTI (road traffic injuries) is a public health problem, it helped in initiating a regulatory process and scientific policy for injury control. 

New highway standards and vehicle design standards were introduced in these countries resulting in major reduction in RTIs. However, late 80s onwards the reduction in RTIs was very small in these countries after implementing the highway design standards and vehicle safety standards. Around this time systems thinking and vision zero policy was introduced for the first time in the Swedish parliament in 1997. Vision Zero demands that the loss of human life in the road transport system is unacceptable and therefore the transport system should be designed in a way that such events do not occur. This means that safety is a more important issue than other issues in the road transport system (except for health-related environmental issues). Mobility, therefore, should follow from safety and cannot be obtained at the expense of safety. 

Over time a large number of interventions were deployed. Regulations to address the most important risk factors were introduced. This included regulating the road environment and vehicle designs.  Achieving this required establishing national agencies, giving them legislative authority and financial resources to maintain a trained technical workforce, develop interventions, evaluate their effects, and scale up interventions that work as part of an ongoing process of continuing improvement. This is a long-term process.

Road Crash Patterns on Highways

National Highways (including expressways) comprise only 2% of the total length of roads in India but account for 36% of the fatalities. The road network of the country is 63.31 lakh km as on 31.03.2019 as reported in Basic Road Statistics, 2018-19, MoRTH.  Table 1 shows the length of different categories of roads and fatalities reported in 2022.

Fatality rate per 100 km of road length is the highest on NH with 45 deaths per 100 km annually and this fact should be the guiding factor in future design considerations. National Highways carry 40% of the total vehicular traffic, but this only partly explains the high crash rate; geometric designs and traffic operations play a major role in contributing to the high crash rates.

Source: MoRTH, 2023 

Table 2 shows the crash patterns reported on different categories of roads.  A majority of those getting killed (68%) on highways in India comprise pedestrians, cyclists and motorcyclists. Pedestrian and motorised two-wheeler (MTW) proportions are very high except on six lane highways where the proportion of truck victims is much higher. The high level of involvement of vulnerable road users on highways is highly unexpected in many high-income countries.

Table 2 Road Traffic Fatalities by type of road user on selected highways

Trucks and buses are involved in about 70% of fatal crashes in both rural and urban areas.  On 4-lane divided roads, head-on collisions comprise 19% of the crashes. Divided 4-lane roads are justified on the basis that these would eliminate the occurrence of head-on collisions. This is probably because tractors and other vehicles go the wrong way when they exit from roadside establishments and the cut in the median is too far away, therefore they prefer to go in the wrong direction. Rear-end collisions (including collisions with parked vehicles) are high on all types of highways including 4-lane highways. This shows that even though more space is available on wider roads, rear-end crashes do not reduce. This is most likely due to poor visibility of vehicles at night, and a severe lack of truck pull-outs and proper rest areas for long-distance truck drivers, forcing operators to park along the highway shoulders and edge-lanes.

Nearly 20% crashes involve hitting a fixed object on expressways clearly highlighting the poor design details. An errant vehicle hitting a fixed object should not lead to fatalities if the design details have been followed correctly. Fixed objects may be a crash barrier, high median, or pole installed for signage. 

Figure 3 shows raised median and incorrect installation of crash barrier (kerb stone in front and low height). An errant vehicle is likely to hit the raised median and turn over or have a tyre burst. Incorrect height of the barrier results in vehicle overturning.

Figure 4 and 5 show distribution of types of fatal and non-fatal crashes observed on Yamuna Expressway.

In fatal crashes, rear end crashes have the highest share, followed by 21% crashes involving roll over, hit guard rail, culvert or bridge, and median. 

Figure 5 shows unprotected concrete blocks at a toll plaza (eastern peripheral Expressway). An errant vehicle hitting the concrete block is likely to have a very severe injury or fatal crash. The guidelines require these to be protected by a crash attenuator. 

The highest share of crashes based on the type of collision are rear-end crashes with 49% for fatal crashes and 35% for non-fatal crashes. The rear-end crashes are reported due to the collision with a breakdown vehicle standing on the hard shoulder. In case of fatal crashes, hit pedestrian crashes are second highest with 11%, followed by hit median with 9%, and hit a guardrail with 6% share in the total crashes respectively. Hit pedestrian crashes incidences are being reported in spite of the expressway being access controlled. Vehicular underpass, cattle underpass, and pedestrian underpass are provided at regular intervals. However, people wait at the entry ramps to board the buses which stop on the expressway near entry and exit ramps as well as near the underpass on the highway. In the case of non-fatal crashes, rollover crashes are the second highest with 22%, followed by the hit median with 13%, and hit guardrail crashes with 11% of the total non-fatal crashes respectively. The contribution of median crossed crashes also has a significant share with 5% and 6% for fatal crashes and for non-fatal crashes respectively.

Hit median crashes suggest that the design of the median is not appropriate for high-speed roads. Expressways have medians which are 6m wide and raised throughout. The height of the curb is 200 mm. Research has established that raised medians are conducive to crashes. Hence raised medians must not be permitted on the expressway. Median crossed crashes indicate the shortcoming or inadequacy of the current design.  The current standards recommend that combination of curb and guardrail must be refrained, however in the case where there is no option other than curb and guardrail combination, the height of curb should not exceed 100mm.

Summary and Way Forward

Understanding of road users who face the highest risk in getting involved in traffic crashes in different categories of roads, locations where a large number of crashes occur and crash patterns observed in different categories of roads can guide the design of roads to reduce fatalities and serious injuries on the roads. 

• High risk road users
  Motorised two wheelers and pedestrians and bicycle users account for nearly 70% of the fatal crashes. Proportion on MTW in fatal crashes has been increasing over the years. 
  1. NH/SH/District Roads: MTW, pedestrians and bicyclists are present on all NH and SH. MTW and pedestrians have the largest share in fatal crash victims.  MTW are involved in 20-30% single vehicle crashes hitting a roadside hazard or skidding from the carriageway.
  2. Expressways: Limited access expressways are not expected to have pedestrian presence. However, 10% of fatal crashes on Delhi Agra expressway are pedestrians. MTW are also involved in fatal crashes on expressways, though the proportion of MTW in fatal crashes is less than their presence on NH/SH. 
• High risk locations
  1. NH/SH/District Roads: Fatal crashes are higher on highway segments passing through habitation or on the segment near habitations especially near junctions. Often bus and three wheelers stop near junctions and bus commuters have to negotiate high speed through traffic to cross the road.
  2. Expressways: Fatal crash cluster near exit and entry ramp on the expressway. Often single vehicle crashes are on straight stretches involving overturned vehicles.  
• Crash patterns of fatal cases
  1. NH/SH/District Roads: Six lane and four lane divided NH and SH have a large share of rear end crashes and crashes involving pedestrians and bicyclists. Undivided roads have head on collisions.  
  2. Expressways: Rear end collisions, followed by hit fixed objects and roll over crashes. Hit fixed objects include median, guard rail, bridge parapet and culverts. Express ways also have pedestrian crashes.

Specific recommendations for National Highways, State Highways, District roads, Expressways

• National Highways: Comprehensive audit of all highways, prioritise highway segments with high crash rates, prepare an implementation plan for five years. At-grade highway segments passing through habitation should be treated like an urban road, with a maximum speed of 50Km/h, with service roads. Where service roads are not feasible, speeds must be restricted to 30 km/h. Rectification of crash barrier installation, median design rectification may be taken up as priority areas on divided highways. 

• State Highways: Revision of speed limits on SH based on surrounding land use and activities. Annual action plan to implement audit recommendations on high crash corridors initially extending to all corridors. Special attention to speed compliance by design. i.e. traffic calming measures near junctions, public transport stops. 

• MDR/District Roads: Revision of speed limits on MDR/ODR based on surrounding land use and activities. Annual action plan to implement audit recommendations on high crash corridors initially extending to all corridors. Special attention to speed compliance by design. i.e. traffic calming measures near junctions, public transport stops. Prepare templates to be used in each districts for ensuring safety near junctions, public transport stops.

• Limited Access Expressway: Ensure compliance of current guidelines (crash barrier installation, median designs, implementation of audit recommendations, speed management near exit and entry ramps. 

In the long term a safety cell/section with trained professionals to initiate research studies, fund research and establish a reliable database for crashes on highways must be established in NHAI, state PWD with trained safety professionals who can monitor Impact assessment of various geometric features and revision of highway standards.

By Geetam Tiwari
Professor Emeritus, TRIP Centre, IIT Delhi

References:

1. Data from locations on 34 national and state highways in India (Tiwari, Mohan and Gupta 2000)
2. Source (Tiwari 2015)
3. Safety effects of paved shoulder width on a four-lane divided rural highway in India: A matched case-control study (Bisht, L.S., & Tiwari, G. 2022)
4. Assessing the Effect of Paved Shoulder Width on Road Traffic Crash Risk on a Six Lane Rural Highway in India (Singh Bisht, L., & Tiwari G. 2023)
5. Assessment of fatal rear-end crash risk factors of an expressway in India: a random parameter NB modeling approach (Bisht, L.S., & Tiwari, G. 2023)