Mexico City's Metrobús. Photo by EMBARQ Mexico.

Traffic safety is an often-overlooked benefit of sustainable transport. New research from EMBARQ shows that investments in sustainable transport projects like Mexico City’s Metrobús (pictured) can reduce traffic crashes and save lives. Photo by EMBARQ Mexico.

Sustainable transport initiatives have gained traction in recent years in developing world cities. This trend can be seen in the growth in Bus Rapid Transit and Busway systems around the world, the new bike-sharing scheme in Mexico City, or the investment in cycling networks in Turkish cities, to name just a few examples. However, these types of initiatives often overlook what should be a key component in their planning – traffic safety. Indeed, while sustainable transport initiatives are usually proposed and evaluated based on their impact on travel times, local air quality, accessibility, or greenhouse gas (GHG) emissions, their potential traffic safety impacts are often overlooked.

A new publication from EMBARQ highlights this issue, exploring the existing literature on the safety impacts of sustainable transport – primarily from the United States and Europe – and adding examples from Latin America and South Asia. The evidence suggests that projects that reduce traffic—such as congestion charging—and those that improve infrastructure—such as high-quality mass transport systems—can have a positive impact on traffic safety, in addition to numerous other co-benefits.

Safety impacts of mass transport

Take the TransMilenio bus rapid transit (BRT) system in Bogotá, Colombia. This BRT system is often hailed as an innovative model for mass transport, particularly among cities in the developing world. In addition to its well-documented impacts on reducing GHG emissions and travel times, the first TransMilenio corridor on Avendia Caracas has had an equally significant though under-acknowledged role in improving traffic safety. Findings show that the BRT has contributed to an estimated reduction in traffic fatalities on the avenue by more than 50 percent, helping avoid more than 200 traffic deaths during its first nine years of operation.

The TransMilenio is not the only BRT system that has dramatically improved traffic safety. BRT and other transit priority projects in Guadalajara, Mexico; Mexico City; Ahmedabad, India; and Melbourne, Australia have similarly curbed traffic crashes and fatalities, while improving the quality of transport in their respective cities. The improved safety record is due mainly to the changes in street infrastructure typically needed to accommodate a BRT  such as creating a central median, making crosswalks shorter, and reducing the number of mixed traffic lanes – all of which tend to contribute to fewer crashes.

Active transport and traffic safety

Cities that have implemented policy and infrastructure to promote cycling have also seen significant safety benefits. Copenhagen and New York City, for example, have both invested in creating or expanding citywide networks of dedicated bike lanes and cycle tracks to promote cycling. In Copenhagen, the total volume of cycling has increased by 28 percent between 1998 and 2009, while the rate of injuries and fatalities to cyclists has decreased by 53 percent. Similarly, New York City had four times as many bicycle commuters in 2010 as it did in 2000, while cycling injury rate (the ratio of cycling injuries to cyclist commuters) declined by more than 70 percent.

It also appears that the safety benefits of cycle infrastructure are not limited to cyclists: A study in New York City found that streets with bike lanes were also safer for pedestrians, a finding that could be attributed to the reduced traffic speeds associated with the introduction of bike lanes and tracks. New York City has also taken key steps to improve walkability and pedestrian infrastructure, with significant benefits for pedestrian safety as a result.

Implications for cities in the developing world

Traffic crashes currently claim more than 1.2 million lives every year, according to the World Health Organization (WHO). That number is increasing, particularly in low and middle-income countries.

In an effort to raise awareness about traffic safety issues and encourage local and national governments to focus on reducing traffic crashes and fatalities, the United Nations declared 2011 to 2020 as the Decade of Action on Road Safety. The initiative includes a clear focus on safe mobility and sustainable urban transport. The WHO has also recognized the importance of sustainable transport in achieving the ambitious goals of the Decade of Action, and its latest Global Status Report on Road Safety includes policies to promote walking and cycling and investment in mass transport as key safety indicators for countries.

Recognizing the potential safety benefits of sustainable transport is a key step, but it is also important to ensure that this translates into high-quality projects on the ground. Through innovative policies and sustainable transport projects, cities in developing countries can meet their growing mobility needs while also significantly improving safety.

For more information on the relationship between sustainable transport and traffic safety, download the issue brief Saving Lives with Sustainable Transport, from EMBARQ, the World Resources Institute’s (WRI) program for sustainable urban transport and planning.

This publication has been possible through funding from Bloomberg Philanthropies.