How can local governments make their streets safer for all? An interview with Seth LaJeunesse

The Economic Mobility Catalog’s Strategy Guide on Traffic and street safety improvements provides guidance for local governments seeking to improve street safety. It was created in partnership with experts and practitioners in the traffic safety and urban design fields, including Seth LaJeunesse, a Senior Research Associate at the University of North Carolina Highway Safety Research Center (UNC HSRC).

In this edited interview, Seth explains how policies and design decisions associated with “Safe Systems” approaches can make communities safer and more livable.

What are some of the most effective ways local governments can improve street safety? How should local governments think about creating safer streets?

What are some specific design features that cities can use to create safer streets?

Start with the question of how to make it safer for people with disabilities trying to navigate environments outside of cars, and build from there. This means: designing car-free or narrower streets; providing wide, accommodating sidewalks separated from car traffic by shade-provisioning street trees; installing accessible curb ramps; constructing elevated, midblock crossings to transit; implementing traffic calming measures; creating "daylit" intersections by removing obstructions near crosswalks to improve visibility; among many other interventions. Intersections are among the most common point of conflict between different cars, bikes, and pedestrians, and there are several relatively low-cost solutions that can have a big impact on pedestrian safety, such as adding sidewalk at-grade signals—the flashing lights that pedestrians can activate when they cross—which is also better for accessibility. Cities can also shorten crossing distances by widening the curb around intersections.

In an urban environment, keeping vehicle operating speeds at 20 mph or lower is paramount. At these speeds, you can mix traffic with a reasonable degree of safety. Where speeds are higher, and more of that kinetic energy is present, physical separation between modes becomes essential.

From a land use perspective, a sense of "enclosure" is important for creating a safer, more inviting environment. Think about elements like trees or natural features. Adding trees and streetlights gives drivers reference points to gauge their speed. Generally, more crowded areas induce drivers to pay better attention to their surroundings.

For cycling, where car speeds are higher than 20 mph, physical separation is always best. Painted bike lanes on higher speed roads, while seemingly helpful, are not terribly effective in terms of safety. Flex posts can help slow down vehicles, but real physical protection with barrier-protected bike lanes or widened multi-use paths are the most effective.

How does enforcement fit into a Safe System approach?

Starting about a century ago, in the 1920s and continuing into the 1960s, a “control” paradigm in traffic safety emerged, wherein newly established traffic engineers and reassigned law enforcement officers controlled traffic using engineering, education, and enforcement. Under this paradigm, the primary offenders were reckless or careless drivers, pedestrians, and poorly designed roads. This was the time the term “jay walking” entered the vernacular and crossing the street in undesignated areas became a crime. We now understand that enforcement should target behaviors that are the greatest risk to others, namely unsafe driving.

Law enforcement can play a vital role as observers of patterns. They know where speeding occurs and where yielding doesn't happen, and can communicate this information to planners and engineers to facilitate environmental changes.

When working to improve street safety, who are the key stakeholders, and what are their roles?

Local and state decision-makers, such as elected officials and city council members, are crucial for setting policy and allocating resources. Implementers, including city planners, engineers, public works departments, and transportation agencies, are responsible for designing, building, and maintaining safe infrastructure.

Safety researchers and injury monitors play important roles in documenting road injury trends, predicting where safety problems may emerge on street networks, developing effective safety measures, and evaluating implemented measures’ effectiveness at reducing road injury.

Community groups, residents, business owners, faith leaders, and parents are essential external stakeholders. They bring lived experience—or “expertise”—and can articulate specific problems and needs. Their involvement is critical for identifying, approving, and even implementing interventions. For example, community members might be most critical to implementing a program on a day-to-day basis, such as participating in neighborhood watch programs for traffic safety.

Engaging legislators, particularly at the state level, can be necessary to secure funding or to advocate for changes to state regulations that impact local street design and financing.

What are some challenges you see for local governments around traffic safety?

A significant challenge is shifting the culture, both internally within government and among the broader public, to be more pro-regulatory and pro-infrastructure change. Prevention is the best medicine, but often local governments only implement a traffic safety solution after a crash.

We need to shift the narrative to focus on the built environment and vehicles, rather than engaging in victim-blaming. Instead of saying, "The driver was going 60 in a 25 zone," we should ask, "Why is it even possible for a driver to go 60 in a 25 zone?" The problem isn't just the individual; it's the system. We’ve seen success on this narrative reframing through social media and community outreach campaigns. It's also important to celebrate moments when advocacy or improvements have been made, reinforcing the positive impact of these changes.

In what ways can a local government prevent disparate impacts as part of traffic safety work?

Local governments and transportation planners should practice participatory justice. This means tapping into people's lived expertise. Individuals who have lived in an area for a long time can articulate the problems they face, even if they don't know the specific technical solutions. Planners and engineers can then identify appropriate solutions and then lend their expertise on design principles and implementation. It's crucial to engage with communities during both high-level planning processes and at the project level.

Additionally, while engineers traditionally think of the typical user, a Safe System perspective demands that we start with the most vulnerable user. For example, consider how someone with a disability will navigate an area and identify where they are the least safe.

Distributive justice is another important area. Local governments need to ensure the distribution of traffic safety resources is fair, and addresses instances of historical disinvestment, rather than simply serving the most vocal or organized communities. Look at which neighborhoods have existing high volume roadways or highways and monitor whether those communities are receiving the necessary investments in safety improvements.

What metrics or indicators do you use to measure the success of a traffic safety initiative?

Measuring operating speeds is critical, especially in areas with different modes of traffic. Modal shift is also a very important indicator since it demonstrates if the changes are actually getting people to change their behavior by walking, cycling, or using mass transit versus driving. In the U.S., we don't always count pedestrians and cyclists effectively, so better methods, such as surveying those at businesses or other destinations, are needed.

Compliance, such as driver yielding behavior at crosswalks or red-light running, are also good metrics. Even air quality, ambient temperatures, and noise levels can be relevant, as traffic safety improvements often align with public health goals.

For early wins, policymakers should look for increases in pedestrian and cyclist activity, a reduction in reported near-misses, and positive community feedback on new infrastructure.