The speed of drivers? The number of drivers? The impatience of drivers? The stress level of residents?

The answer is: yes.

At Kittelson, we describe traffic calming as adjusting levers to improve transportation safety in neighborhoods, which does indeed calm all those things.

We can’t remove conflict points – but we can make them safer through design improvements.

We can’t eliminate cars from driving on neighborhood streets – but we can reduce the speed of vehicles.

We can’t solve the problem by simply diverting drivers to other streets – but we can make physical improvements so when they enter a neighborhood, they’re entering on that neighborhood’s terms.

An Illustrated Guide to Traffic Calming by Hass Klau puts it this way: “Traffic calming is a term that has emerged in Europe to describe a full range of methods to slow cars, but not necessarily ban them, as they move through commercial and residential neighborhoods.” Traffic calming is about making neighborhoods better places to live, work, and play.

Benefits of Traffic Calming

The most apparent benefit to a residential or commercial neighborhood from traffic calming is safety. Driving more slowly and carefully leads to fewer and less severe crashes. Residents, particularly families with young children, feel more comfortable walking or cycling through their neighborhood when they aren’t worried about fast-moving cars.

A second important benefit is that traffic calming encourages more equitable balance among modes. When drivers are put in check, it sends the message that they don’t own the road. Slower driving speeds mean cyclists and pedestrians get more time to detect and avoid cars.

Thirdly, traffic calming can improve the health of a neighborhood. As residents feel safer jumping on bicycles or going on walks, the physical activity has plenty of health benefits. And traffic calming can actually improve the air in which that physical activity take place. Slower moving vehicles generally emit fewer pollutants, leading to better air quality.

Traffic calming can also be beautiful! Traffic calming often involves simplifying intersection design to make it easier to navigate through the intersection, which results in more predictable movements from all modes. It also provides space for green infrastructure or street furniture which can humanize the streetscape.

FHWA lists several additional benefits of traffic calming, including decreases in crime, fuel consumption, and vehicle noise.

Traffic Calming in Boston, MA

Traffic calming encourages a more equitable balance among transportation modes.

Traffic calming encourages a more equitable balance among transportation modes. Drawing by John Paul Weesner.


Common Traffic Calming Techniques

There is no one-size-fits-all solution to traffic calming because every neighborhood has unique needs. The following techniques, however, are common approaches in a traffic calmer’s toolbox:

  • Repurpose “auto-owned” space. Medians, curb extensions, and road diets are all techniques that reduce space designated for cars. This reclaimed space can be used for landscaping, parking, pedestrian amenities, and more.
  • Limit vehicular access through physical barriers. Limiting connectivity is usually counterproductive, but In some cases restricting vehicle access can solve problems in other parts of the network.
  • Implement roundabouts at intersections. Roundabouts reduce conflict points and create a calm, steady flow of traffic.
  • Install vertical measures (such as speed humps) and horizontal measures (such as medians) that require vehicles to slow down.
  • Use signing and striping techniques. Visual cues can affect driver behavior and educate drivers how to proceed through a neighborhood.
  • Educate community members. The City of La Mesa cites this interesting tool in the traffic calming toolbox. Conversations, meetings, e-mails, handouts, and digital campaigns regarding neighborhood traffic, pedestrian safety issues, and alternate forms of transportation can get at the goal of behavior change.

Traffic Calming in Action on Urban Streets

While traffic calming is by no means limited to major cities, it can have significant impact on the quality of life in urban neighborhoods. Urban settings face unique challenges that underscore the importance of traffic calming measures. For example, city neighborhoods often have narrower streets, dense on-street parking, and the need to accommodate through traffic as part of a grid network.

Kittelson offices in major cities such as Washington, D.C., Boston, San Francisco, Philadelphia and Cincinnati give us a firsthand perspective on the needs facing urban transportation networks. Here’s how a few of these cities are tackling traffic calming.

San Francisco residents who are concerned about mid-block speeding in their neighborhoods apply for San Francisco Municipal Transportation Agency (SFMTA)’s Residential Traffic Calming Program. The City assesses traffic conditions on each street to determine which blocks demonstrate the greatest need for traffic calming, then select streets and implement physical treatments to slow traffic. Kittelson helped SFMTA assess program effectiveness to understand large-scale change from these efforts.

The City of Boston offers the Neighborhood Slow Streets Program, which takes a zone-based approach to reducing speeds in Boston neighborhoods. The program uses low-cost fixes with a goal of slowing drivers to 20 MPH and making streets feel more inviting to everyone who uses them. Kittelson has conducted analyses for 12 neighborhoods, five of which are in the final design stage.

In Washington, D.C., Kittelson has been supporting the District Department of Transportation (DDOT)‘s Vision Zero initiative. Projects include the review of neighborhoods and complicated intersections from the perspective of all users, keeping the larger, more permanent vision in mind as we develop alternatives.

Keys for Long-Term Success

When we analyze intersections, we often find that solutions implemented in the past simply resulted in layers of “band-aids.” It’s critical to understand the underlying issues and see traffic calming as a long-term game. Kittelson recommends considering the following elements in a traffic calming approach:

  • Tactical urbanism: We use this phrase to refer to making physical improvements to a community’s built environment with long-term improvement in mind.
  • Community context: Every neighborhood sits in a unique context and has unique needs. Along with conducting speed and safety analyses, the best way you can truly understand the heart of the issue is to get out, walk through the neighborhood, and listen to residents.
  • Network-based approach: As we mentioned at the beginning of this post, diverting traffic from one street to another only relocates the problem. By considering all parallel streets together, we can creatively encourage behavior change, moving traffic through neighborhoods more slowly and safely. The City of Boston’s Neighborhood Slow Streets Program is a good example of this.

Improving quality of life in the communities we serve will always be central to our work at Kittelson. Feel free to contact us to talk further about traffic calming, or other challenges facing urban streets!