Across the nation, cities, including Hyattsville and Mount Rainier, have embraced artworks painted directly on streets as a technique to calm traffic and beautify communities. In our February “Science of the City” article, we described the extensive Bloomsburg Foundation research project indicating that asphalt art can significantly reduce pedestrian deaths and injuries.
This piece examines some of the technical challenges involved in creating safe and effective designs, and the political developments that have already forced the removal of hundreds of street artworks and that may drive the practice to extinction nationwide.
Street art can force drivers and pedestrians to interpret and react to new and inconsistent visual cues. For example, on Gallatin Street near the Hyattsville Municipal Building, brightly colored areas indicate places where cars aren’t allowed. However, at the juncture of Jefferson and 40th streets, the colored areas are in the middle of the intersection to denote where people shouldn’t be walking.
There has long been a debate over whether street art conflicts with the Federal Highway Administration (FHA) Manual on Uniform Traffic Control Devices (MUTCD), which seeks to “promote national consistency in the use, installation, and operation of traffic control devices.” A 2009 FHA memo essentially argued that all street art violated MUTCD guidelines.
Nevertheless, street art continued to gain popularity nationwide. In Maryland, the state’s Highway Safety Office actively began collaborating with the Maryland Institute College of Art to promote it as a safety measure.
According to Graham Coreil-Allen, who owns the design firm Graham Projects, which produced the Jefferson Street mural and many others, “As evidence emerged that street art was successful for traffic calming, or at least did not increase accidents, the latest official revision of MUTCD, which was in 2023, interpreted it as legal.” He elaborated, however, that designs should not include shapes that could be mistaken for standard traffic signs, such as yellow triangles, or physical objects like orange cones that might be temporarily set up in the roadway. Additionally, street art is only appropriate for traffic conditions that do not change. For example, such art should not be used in intersections where left or right turns are prohibited during certain hours of the day.
Some creative designs for asphalt art can have unintended consequences. After a student was killed in a crosswalk in Medford, Massachusetts, the town adopted “Icelandic crosswalks” for their elementary schools. These crosswalks slow cars by creating the optical illusion that the stripes are actually three-dimensional raised, floating bars. However, when officials from Cambridge, Massachusetts, researched the idea, they rejected it, concluding that 10–14% of drivers found the effect so realistic that they suddenly stopped or swerved, creating a safety hazard.
There have also been concerns about how street art will affect what is expected to be a growing number of self-driving cars. These vehicles are often programmed to follow standard lane lines and markings, and there is a question of whether they will be able to differentiate them from artistic designs.
But the biggest threat to the future of street art is probably America’s polarized politics. Right after President Donald Trump’s second term began, U.S. Rep. Andrew Clyde (R-Ga.) introduced legislation that would require the District to repaint street artwork and rename its Black Lives Matter Plaza or lose millions of dollars in transportation funding. D.C. Mayor Muriel Bowser ordered the removal of the mural, and the legislation never advanced.
Across the nation, the most commonly attacked street artworks are those perceived to relate to LGBTQ pride. In June 2023, the multicolored block design at Jefferson Street and 40th Avenue was defaced by a man who mistook it for representing LGBTQ pride, according to a Hyattsville police Facebook post.
In Texas and Florida, dozens of LGBTQ pride murals have been deliberately removed, including the rainbow crosswalks outside Pulse Nightclub, the gay dance club where 49 clubgoers were killed and another 58 injured in 2016. Their governors are actively enforcing and echoing Trump’s Secretary of Transportation Sean Duffy’s decision that street art violates MUTCD requirements for uniformity and threatens public safety.
In a July 2025 media post, Duffy wrote, “Taxpayers expect their dollars to fund safe streets, not rainbow crosswalks.” A day later, Florida’s transportation secretary, Jared Perdue, wrote that Florida wants to “keep our transportation facilities free & clear of political ideologies.” In response, the vice mayor of Delray Beach, Rob Long, stated, “We all know this is not about traffic safety, it’s political, where symbols of inclusion are targeted precisely because they represent acceptance.”
Even though the removal of street murals depicting Black and LGBTQ pride may be painful to the groups represented, they constitute just a tiny fraction of street artwork. So why is street art like that in the City of Salisbury, commissioned in 2025 and stipulating that it be “free of political or ideological influence,” also threatened?
The answer lies in U.S. Supreme Court and Georgia Appeals Court rulings that Missouri and Georgia could not prevent branches of the Ku Klux Klan from volunteering to support the cleanup of state highways because of their political ideology. Rather than tolerate signs saying “This stretch of highway has been adopted by the KKK,” Georgia completely withdrew from the Adopt-A-Highway program. Missouri accepted the Klan’s application but disqualified the group a few years later because it did not collect any litter.
Therefore, to prevent being accused of discriminating against LGBTQ or Black communities, Texas and Florida have required the removal of all street art, including a “Back the Blue” mural supporting local police. It is estimated that this might destroy as many as 440 different street murals across Florida, including many that were previously approved by the Florida Department of Transportation.
The threat of losing state and federal highway funds is a powerful weapon. As he agreed to comply with Texas Gov. Greg Abbott’s directive to remove any and all political ideologies from public streets, Austin Mayor Kirk Watson wrote, “Failure to remove the paint would jeopardize hundreds of millions of dollars. Austin Transportation and Public Works alone currently has $175 million in state and federal grant funding.”
————————–
Paul Ruffins is a citizen scientist and a professor of curiosity.