The Open Streets Minneapolis event (above, in 2018) temporarily closes major streets to car traffic, opening them up for walking, cycling, and other community uses. (Flickr / Fibonacci Blue)

4 ways to go from “streets for traffic” to “streets for people”

A new study evaluates some common street design interventions that should be in every city’s toolbox.

Eric Jaffe
May 29, 2020 · 7 min read

The Covid-19 pandemic has led many cities around the world to adapt their streets on the fly — mostly in ways that provide less space for cars and more for people. Some have added temporary bike lanes as a transit alternative for essential workers or an exercise option for populations on lockdown. Others have closed entire streets to car traffic so pedestrians can have more room to roam at a safe social distance.

It remains to be seen whether or not such changes will persist as the pandemic fades, especially if city residents flock to their cars out of fear of riding subways and buses. But if the only legacy of these efforts is a greater inclination to test out new street interventions, that would still be a big win for cities. A long line of evidence shows that, even when cities aren’t facing a generational public health threat, street design explorations can improve well-being, social cohesion, sustainable transportation, and other quality-of-life areas.

A new paper helpfully compiles much of that evidence, with a focus on four common street design explorations: re-marking streets, repurposing parking, repurposing street sections, and closing whole streets. The work, published in the journal Transport Reviews, comes from planning scholar Luca Bertolini of the University of Amsterdam. Bertolini’s aim is to support a policy shift “away from ‘streets for traffic,’ and towards ‘streets for people.’ ”

In the long history of roads, street markings are a fairly recent phenomenon — only entering the scene in the early 20th century, as the need to separate fast-moving vehicles from other travelers became clear. With street markings delineating more and more space for cars over the decades, the recent re-marking effort aims to redraw some of those lines for other uses.

Bertolini focuses on a type of re-marking called “intersection repairs,” which emerged in Portland in 1997, when residents of the Sellwood neighborhood redesigned an intersection into a community space, complete with lines for kiosks, benches, and a children’s playhouse. The city initially wanted to remove the unsanctioned sketching but relented in the face of popular demand, later adopting an ordinance allowing such projects.

As of mid-2019, Portland had implemented more than 60 intersection repair projects, and the method is now mimicked in cities around the world. Other re-marking efforts include etching out lines for temporary bike lanes or pedestrian crossings. Some cities have even experimented with a “shared streets” model that (safely) echoes the pre-vehicle days, when all forms of traffic navigated around unmarked streets.

One study of another late-’90s Portland intersection repair found that, relative to a control site, the re-marking effort was associated with more social interactions (32 percent vs 7 percent), higher neighborhood ratings (65 percent vs 35 percent), and more self-reports of feeling in excellent or very good health (86 percent vs 70 percent).

Outdoor diners enjoy a San Francisco parklet in 2013. (Paul Krueger / Flickr)

Thanks to the work of Donald Shoup and other urban scholars, the downsides of free (or cheap) street parking in cities are now widely known. As drivers circle for spaces, street parking significantly increases traffic congestion and pollution. It causes double parking, which reduces pedestrian safety, and it reduces space for other travel modes, which makes it harder for city residents to get around without owning a car.

Bertolini focuses on parklets as one way to repurpose space devoted to car parking for other uses. A parklet transforms a street parking space into a more public space through temporary installations of outdoor seating, public art, tree plantings, and bike racks, among other social amenities. The parklet concept dates back to 2005, writes Bertolini, when a design firm called Rebar paid a parking meter for a parking space but used it as a public space instead.

Since then the parklet concept has gone global. It’s now fairly common for cities to permit parklets, often with a local sponsor (such as a nearby restaurant) responsible for installation and maintenance. By 2016, some 80 cities around the world had parklet programs, and in recent years, an annual one-day parklet event called PARK(ing) Day has been celebrated in at least 162 cities across 35 countries.

While ground-floor businesses in cities often object to the removal of street-parking spaces, the evidence suggests that such fears tend to be misguided, as pedestrians or cyclists end up spending as much or more money in shops as drivers do. In Toronto, for example, a recent street design pilot trading parking spaces for bike lanes found that monthly spending, customers, and visit frequency all rose.

For all the benefits of re-marking streets and repurposing street parking, such interventions still reserve the majority of street space for vehicles. Some programs the next step: shutting down long sections of a street to car traffic.

The concept of pedestrianizing streets goes back decades; in the 1960s, pioneers Jan and Ingrid Gehl made the data-driven case for transforming Copenhagen’s main thoroughfare, Strøget, into a people-first public space. Bertolini spotlights New York City’s “pavement to plazas” program as a recent model of such efforts.

The Times Square pedestrian plaza dramatically improved street safety and local activity, even as it had no negative impact on traffic flow. (NYC DOT / Flickr)

Launched in 2007 by transportation chief Janette Sadik-Khan, the program closed entire sections of New York City streets to cars and encouraged people to stroll these new pedestrian plazas, the most famous of which closed off part of Times Square. By 2014, New York was home to 59 pop-up plazas. Since then, cities around the world have adopted similar efforts on a temporary or seasonal basis — in some cases making the popular changes permanent.

The evidence — documented in city reports, as well as in a book by Sadik-Khan — shows an abundance of quality-of-life benefits for pop-up plazas. After the Times Square intervention, for example, pedestrian injuries fell 35 percent. Consistent with the parking space conversions, pop-up plazas have also been linked to a rise in retail sales. And the closures have no negative impact on car traffic when applied in a careful manner.

The ultimate street exploration involves closing down an entire street, or set of streets, to traditional traffic. Here Bertolini focuses on two expressions of this effort: ciclovias (“open streets”) and “play” streets.

Ciclovias are temporary street closures, often made in conjunction with a set of community activities planned for the street space. While they date back to Bogota, Colombia, in the 1970s, ciclovias really took off in the last 20 years. In 2015 alone, some 500 cities around the world — spanning every continent — held at least one ciclovia event.

Bertolini documents “sizable positive impacts” on physical activity, social interaction, and social capital. In Bogota, for example, children who frequently use ciclovias on Sundays engage in greater amounts of vigorous physical activity and less sedentary time, compared with occasional users or non-users.

Whereas ciclovias aim to engage a wide community, a related effort focuses on repurposing whole streets specifically for children’s play. In Ghent, Belgium, where play streets have become a regular event since 1998, one study found that physical activity increased and sedentary time decreased for kids who lived near play streets, relative to those who lived near control streets.

Given all the benefits of temporary street explorations, Bertolini concludes with a call for cities to get more comfortable with such interventions. “The key challenge seems finding ways to not just tolerate, but rather proactively shape institutional and physical space for experimentation, and for learning from it.”

An institutional change would be welcome. New York City, a leader of American street design, still faced pushback against repurposing streets for people even at the height of the pandemic, when car traffic all but disappeared. Across the U.S., such efforts still feel like isolated battles instead of fundamental shifts.

Covid-19 may help change mindsets. The more familiar a city becomes with a given street exploration, the larger its design toolbox — and thus its resiliency. Design innovations that embed more flexibility into the streetscape, such as “dynamic curbs” that can quickly change their uses, can also make street explorations feel more familiar and less experimental.

Because the ultimate aim is not just to do more temporary explorations, but to improve quality of life over the long term. Reducing car-ownership, air pollution, street deaths, traffic congestion, even housing costs — achieving all these goals starts with recognizing the role that street design plays.

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