Transportation, like infrastructure, is a broad term. Not only is it planes, trains, and automobiles, transportation is also bikes, subways, and buses. For cities and urban planners in particular, transportation is a question of balancing the competing needs of different groups of citizens. In Washington, D.C., biking can often become a surprisingly contentious issue that pits walkers, drivers, and bikers against each other as city planners determine whether to allocate limited street space to additional sidewalk space or extra lanes. Recent surveys of the city have further complicated the debate, showing that minority residents rely more heavily on buses and may be underserved by attempts to promote biking in certain neighborhoods.

The D.C. Policy Center, a think tank, studied survey research from the American Community Survey, which examines demographic and community trends across the country. Looking at D.C., the researchers found that modes of transportation exhibit strong demographic splits.

“Policies meant to make the city more walkable and bikable can be perceived to amplify transportation injustices—or, at a minimum, change how these communities function,” the study found.

According to the survey, D.C.’s bikers are younger and wealthier than the average city resident. Although the median age of D.C. residents was 36 in 2015, when the study was taken, bikers were generally 34 years old, and walkers only 30. They also tend to be wealthier than the average resident.

“If we were to adjust for age differences, we would find that those who walk and bike to work are richer than those who drive or take the bus,” the study found. “That is why they can afford to live close to where they work.”

Some of the survey’s results are as to be expected. Most people who bike or walk (nearly 37,000) are clustered in the city center. Fewer of the bikers and walkers live east of the Potomoc River, in Anacostia.

Transportation often exposes pre-existing tensions caused by gentrification. Over the course of the last few years, many historically minority neighborhoods are becoming increasingly white and college-educated. One such neighborhood in D.C. is Shaw, which was originally founded by freed slaves and which retained its African-American history through until the start of the 21st century. Within the last 10 years, however, rising rent pushed educated young professionals into downtown neighborhoods previously considered unsafe. Today, Shaw’s black population is roughly equal to its Caucasian one.

This has an effect on the transportation needs of the area. When neighborhoods decide on different transit options, they are increasingly forced to choose between policies that will benefit one racial group more than another. Data shows that D.C.’s transit usage breaks along racial lines.

“Among D.C. residents who work in the city, nearly 41,000 blacks drive to work compared to 32,000 whites,” writes the D.C. Policy Center, an area think tank. “When it comes to public transportation, whites more frequently take the Metro; blacks more frequently take the bus.”

Additionally, only 5,765 African American residents walked to work, compared to 29,000 whites. The numbers show that policies that promote particular methods of transportation are likely to be seen as exacerbating pre-existing racial divides.

Washington has been making biking and walking important parts of its transit planning for several years. In 2015, under the administration of Mayor Vincent Grey, the city released MoveDC, outlining planned transportation policies for the city. The plan sought to both “strengthen connections between neighborhoods” and also relieve traffic congestion by promoting walking and biking as alternative transportation methods.

Under the terms of the plan, the city is working to build 200 miles of on-street bike lanes and off-street multi-use trails, while also improving sidewalks and pedestrian crossings. Despite these infrastructure improvements, it seems like the root of D.C.’s transit problems is in part demographic. Improving transit by investing in bike and metro options disproportionately benefits higher income residents. Today, businesses are required to offer employees a variety of transit benefits, including parking, metro, and even biking benefits. However, these benefits do not address the underlying problem, namely that a person’s transportation choices are affected by where they life.

“To be clear, bike lanes are good. Safe sidewalks are good. They are relatively cheap investments that reduce congestion and help improve health,” writes Yesim Sayin Taylor, executive director of the D.C. Policy Center. “But beyond investing in infrastructure and improving safety, D.C. Government does not need to favor those who walk or bike to work. And it should not favor those who drive either.”

Instead, Taylor recommends that the city look at its broader housing and transportation policies.

“We should expand D.C.’s stock of affordable housing and promote dense, mixed-income developments along transit-accessible corridors,” she says, “improve both Metro and bus networks so that they are an accessible and reliable option for all residents.”

As the numbers show, the issue is about more than just bike lanes. Instead, transportation exposes ways in which Washington’s shifting neighborhoods require different transportation approaches. The choice between a bike lane and a bus stop is more than just between two modes of transportation, it also impacts different racial and economic groups in the city.

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