The key to safer roads? Narrow the lanes.

The current national epidemic of speeding, distracted driving and other risky vehicle behaviors—accompanied by the increase these behaviors cause in automobile, bicycle and pedestrian fatalities—has led many state and local governments to intensify their efforts to implement effective Vision Zero strategies to promote safer mobility. But while Vision Zero traditionally has focused on tactics such as lower speed limits, protected bike lanes and curb extensions, a study late last year by the Johns Hopkins Bloomberg School of Public Health has provided compelling evidence that a new approach can be added to the toolbox to significantly enhance safety for all road users.

Unlike previous investigations into this approach, the John Hopkins study meticulously analyzed the impact of road lane width on traffic safety. Researchers examined data from various urban and suburban settings, focusing specifically on accident rates, vehicle speeds and overall road safety. Their findings revealed a clear, and perhaps surprising, correlation: Narrower lanes, typically ranging from 10 to 11 feet, lowered vehicle speeds and reduced accident rates when compared to the standard 12-foot lanes found in most U.S. cities.

Researchers attributed this change primarily to driver behavior. When drivers perceive the road to be more constricted, they tend to be more cautious. This heightened awareness leads to slower driving speeds and more attentive driving. In short, the psychological impact of a narrower space creates a sense of constraint that naturally encourages safer driving habits.

This phenomenon was evident throughout the study's findings, where roads with narrower lanes regularly experienced a marked reduction in speed-related accidents. This led researchers to conclude that by reducing lane width, municipalities can effectively calm traffic without the need for extensive traffic calming measures, such as speed bumps or chicanes (artificial narrowings or turns on a road that will slow traffic speed).

Narrower lanes also create more space for other road users, namely pedestrians and cyclists. By reallocating road space from wider vehicle lanes to sidewalks and bike lanes, cities can promote safer, more inclusive transportation networks.

The study noted that roads with narrower lanes and dedicated bike lanes or expanded sidewalks experience fewer accidents involving pedestrians and cyclists. In cities like Amsterdam and Copenhagen, for example, where narrow lanes and comprehensive cycling infrastructure are standard, the rates of pedestrian and cyclist accidents are significantly lower than in cities with wider lanes and less accommodating infrastructure. The example these cities provide clearly indicates that a balanced approach to road design which considers all users leads to safer and more vibrant urban environments.

Researchers concluded that narrower lanes also contribute to environmental sustainability and public health. Reduced vehicle speeds lead to lower emissions since cars operate more efficiently at moderate speeds by avoiding the rapid acceleration and braking associated with higher speeds. Moreover, encouraging cycling and walking by reallocating road space can reduce the overall number of vehicles on the road, further decreasing pollution levels.

From a public health perspective, promoting walking and cycling through safer road design has the added benefit of increasing physical activity among urban populations. Regular physical activity is crucial for combating various health issues, including obesity, cardiovascular diseases, and diabetes. By making streets safer for these activities, cities can foster healthier communities.

While the John Hopkins study clearly makes the case for narrowing lanes in urban areas, actual implementation requires careful planning and consideration of local conditions. Not all roads are suitable for narrower lanes, particularly those with high volumes of heavy trucks or buses. Many urban streets and residential areas, however, can benefit from this approach. Integrating narrow lanes with other traffic calming measures, such as roundabouts or raised crosswalks, can further enhance safety.

To effectively implement a lane narrowing strategy, municipalities should conduct thorough traffic studies, including data collection and traffic counts, to understand current usage patterns; engage with the community to address concerns and gather support; and ensure that any road changes are clearly communicated and have sufficient signage. 

Successful examples of narrow lane implementation can be seen in cities like New York, where the Vision Zero initiative has reconfigured many streets with narrower lanes, leading to significant reductions in traffic fatalities and injuries. Similarly, the adoption of narrower lanes on certain streets in Toronto has contributed to improved safety outcomes.

In conclusion, the study provides ample evidence supporting the safety benefits of narrower road lanes. By emphasizing the importance of designing roads that encourage safer driving behaviors, narrower lanes not only slow traffic but also create a more inclusive and sustainable urban environment that accommodates pedestrians and cyclists in addition to drivers.

As urban populations continue to grow, and the demand for safer, more efficient transportation networks increases, adopting narrower lanes can be a key strategy for cities of all sizes. By prioritizing safety through thoughtful road design, streets that are safer for everyone can be created, fostering healthier, more vibrant communities.

The narrow lane concept is not just about reducing the width of the road. It is also about expanding our understanding of road safety and embracing a more holistic approach to urban mobility. With the evidence at hand and practical examples demonstrating success, it’s time for more cities and states to consider narrower lanes as a vital component of their road safety strategies.

Wes Guckert, PTP, is president & CEO of The Traffic Group, a service-disabled veteran-owned small business (SDVOSB), Maryland-based traffic engineering and transportation planning firm. For more info: www.trafficgroup.com or follow them on LinkedIn.