Nearly a Century Later, Redlining Still Slows Ambulances

In U.S. cities once marked “hazardous” on federal housing maps, ambulances are still slower to arrive than in neighborhoods rated most desirable nearly a century ago. A new Rutgers study spanning 236 urban areas found that residents of historically redlined communities remain less likely to receive rapid emergency medical services, a gap researchers say is rooted in discriminatory policies from the 1930s.

National Patterns of Delayed Care

The analysis, published in JAMA Network Open, used modern traffic data, 2020 Census block groups, and historic Home Owners’ Loan Corporation (HOLC) maps to measure five-minute drive times from 42,472 EMS stations. Researchers found that 7.06% of residents in Grade D tracts (redlined as “hazardous”) lacked rapid EMS access compared with 4.36% in Grade A (“most desirable”) areas. Across the mapped zones, 2.2 million of 41 million residents could not count on an ambulance arriving within the National Fire Protection Association’s benchmark for critical calls.

Overall, the odds of response times exceeding five minutes were 67% higher in historically redlined neighborhoods. The gap appeared in every U.S. region, with the starkest divide in the Great Lakes, where redlined residents were nearly three times as likely to be outside the five-minute reach of an ambulance.

Historical Roots, Modern Consequences

HOLC grades were color-coded green for “best,” blue for “still desirable,” yellow for “declining,” and red for “hazardous.” While these maps were most used in the 1930s, the grading system was not outlawed until 1968. Lead author Cherisse Berry, professor of surgery and vice chair of academic surgery at Rutgers New Jersey Medical School, said the link between past housing policy and present-day survival chances is unmistakable.

“Location alone determines whether people get the rapid care that saves lives,” said Berry, who is also a trauma surgeon and director of research at University Hospital’s Eric Munoz Trauma Center.

Berry’s team overlaid today’s street grid on historic HOLC maps, then calculated distances from each census block’s population center to the nearest EMS station, adjusting for average driving speeds.

Demographics and Health Equity

Redlined tracts still have more Black and Hispanic residents, higher population density, and lower median incomes than Grade A tracts. The authors describe redlining as both a political determinant of health, shaping residential segregation and community disinvestment, and a structural determinant, influencing the distribution of resources like EMS coverage.

“It is time to dismantle the structural determinants of health that perpetuate preventable deaths,” Berry said. “We must redesign prehospital systems to achieve spatial justice, by embedding equity metrics into EMS policy, targeting investments to historically excluded neighborhoods, and holding agencies accountable for equitable access.”

Possible Solutions

The team suggests using public dashboards, repositioning EMS units with geographic information system tools, and adding equity measures to certificate-of-need reviews. Targeted investments, they argue, could cut mortality significantly, especially in areas where residents face both slower 911 responses and higher rates of chronic disease.

Outside experts writing in an accompanying editorial say the work offers a “road map for righting persistent wrongs.” While the study modeled travel distances rather than real-world dispatch records, its authors stress that even small reductions in ambulance drive times could save lives.

Key Findings

• 236 U.S. cities analyzed using modern and historical mapping data
• 7.06% of residents in redlined tracts lack rapid EMS access vs. 4.36% in Grade A areas
• Odds of exceeding five-minute response times are 67% higher in redlined neighborhoods
• Disparities persist across all regions, worst in the Great Lakes

Journal: JAMA Network Open, published online August 5, 2025

DOI: 10.1001/jamanetworkopen.2025.25681