Segregation, City Size, and Public Health in the United States, 1900–40

Investment in water and sewers was one of the most important public health interventions during the early 20th century, accounting for 50 percent of the decrease in U.S. mortality between 1900 and 1940. During this time, however, cities were also becoming increasingly segregated. This paper seeks to understand the consequences of segregation on public health. We pair city-level segregation estimates by decade with mortality data tabulated by both race and disease. The result is a panel dataset on mortality and segregation for 667 cities. Results indicate that increasing segregation by one standard deviation would have raised the black-white typhoid mortality gap by about 80 percentage points. We demonstrate that these impacts were more pronounced in large cities and disappeared when looking at smaller cities suggesting that racial health gaps may have been exacerbated when cities became large enough to support public water and sewerage projects and discriminate in access to those resources.