Blight is demonstrably hard on city budgets — particularly the coffers of local police and fire departments, which have to deal with the increased levels of crime and arson around dilapidated properties. Not surprisingly, though, it’s also hard on people, even if its impact is harder to track in dollar signs.

A new study from Columbia University Mailman School of Public Health tackles the more complicated (but no less important) social impacts of blight, with Philadelphia as its canvas. Its findings: Cleaning up distressed lots doesn’t just increase residents’ feelings of safety, it impacts their actual safety as well.

Plan Philly reports:

The 38-month analysis of 541 randomly selected vacant lots around the city found that crimes including gun assaults, robbery, burglary, and illegal drug trades decreased by at least nine percent in all neighborhoods that experienced a blight cleanup. Poor sections of Kensington/Allegheny, the Southwest, and North Philly experienced the most significant decrease in crime when the conditions of lots improved, said coauthor John MacDonald, a University of Pennsylvania professor of criminology and sociology. New data recently released by the city ranks these same areas as among the city’s most heavily littered with trash and debris.

The process was simple enough. Researchers either appointed lots to receive inexpensive tweaks like new lawn, trash removal and regrading to stay unchanged as control sites. Crime data was then gathered from police reports, as well as interviews from randomly-selected residents (Philly Mag has more details).

The findings could be significant nationally, and not just because they mention a decrease in gun assaults. As the study points out, about 15 percent of the land in US cities is deemed vacant or abandoned — “an area roughly the size of Switzerland.” And cities don’t have to undertake pricey restoration projects to remedy their blight, which come with the risk of gentrification.

“Many cities have focused on complicated and expensive responses to their vacant land problem as part of large urban transformation initiatives,” the report states. “While these strategies can change local economic conditions, they also can have the unintended consequence of displacing people who do not wish to move, create further entrenched neighborhood segregation and may not adequately address the widespread problem of vacant land that chiefly affects low-resource neighborhoods.”

Restoration of land with very simple tweaks, the researchers claim, “can be an effective and scalable infrastructure intervention for gun violence, crime and fear in urban neighborhoods.”

The report is available here.

Rachel Dovey is an award-winning freelance writer and former USC Annenberg fellow living at the northern tip of California’s Bay Area. She writes about infrastructure, water and climate change and has been published by Bust, Wired, Paste, SF Weekly, the East Bay Express and the North Bay Bohemian

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