Researchers conduct first quantitative analysis of water, sewer access disparities in 75 NC counties

April 16, 2018

A new study that examined access to water and sewer services in areas bordered by large municipalities suggests that two primary groups in North Carolina remain underserved: lower-income African-American populations and higher-income non-African-American populations.

Previous evidence has identified potential racial disparities in access to community water and sewer service in some parts of North Carolina, and these additional details clarify for whom services are most likely to be lacking.

Dr. Jacqueline MacDonald Gibson

Dr. Jacqueline MacDonald Gibson

Hannah Gordon Leker

Hannah Gordon Leker

Motivated by a request from the former North Carolina state public health director, two researchers associated with the University of North Carolina at Chapel Hill’s Gillings School of Global Public Health have performed the first quantitative, multi-county disparities analysis. Using publicly available data from 75 N.C. counties, they identified areas surrounded by or bordered by large municipalities, also known as “peri-urban” areas, that lacked community water and/or sewer service.

The full article on this analysis, titled “Relationship between race and community water and sewer service in North Carolina, USA,” was published online March 21 by the journal PLOS ONE.

Hannah Gordon Leker, MSPH, a two-time alumna of the Gillings School’s Department of Environmental Sciences and Engineering, currently a public health policy analyst with the Maryland Department of Health, was first author of the study. Her co-author was Jacqueline MacDonald Gibson, PhD, associate professor of environmental sciences and engineering at the Gillings School. Macdonald Gibson also is an RTI University Scholar and co-author of a large body of literature on the topic of water access and water quality in North Carolina.

To evaluate the relationship between race and access to services in peri-urban areas, the two researchers performed a logistic regression, controlling for population density, median home value, urban status and percent white population in the adjacent municipality.

In the peri-urban areas analyzed, 67 percent of the population lacked community sewer service, 33 percent lacked community water service and 72 percent lacked at least one of the two services. In areas other than those with no African-American residents at all, the odds of having community water service or at least one of the two services (water or sewer) were highest for census blocks with a small proportion of African-American residents and lowest in 100 percent African-American census blocks. This trend did not hold true, however, for access to community sewer service alone.

For example, the odds of having community water service were 85 percent higher in areas where the African-American population was between zero and 22 percent, compared to areas with a 100 percent African-American population.

Surprisingly, the peri-urban census blocks with zero percent African-American population had the lowest odds of accessing community sewer service, despite the fact that, among all areas lacking an essential service, those with no African-American residents were the wealthiest.

Thus, the findings suggest two unserved groups of differing racial and socioeconomic status: (1) lower-income African-American populations that potentially were excluded from municipal services during the era of legal racial segregation, and (2) higher-income non-African-American populations.

This conclusion supports previous research revealing that some unincorporated peri-urban areas are older, less wealthy African-American communities that potentially could have been excluded from access to municipal services during the era of legally sanctioned racial segregation.

“Some of these communities are like donut holes in the middle of cities and towns,” said MacDonald Gibson. “There’s evidence from previous research by demographers that shows how majority white town governments in the past intentionally excluded these areas from city services, and in some cases those historic structural disparities remain.”

In contrast, some underserved areas are new, suburban, all-white communities, in which residents generally are better able to afford to properly maintain private wells and septic systems in order to avoid waterborne diseases.

“This study reveals the importance of accounting for different categories of socioeconomic and racial groups that may be unserved by vital public health services.” Leker explained. “Additionally, the findings show that there may be greater racial disparities in access to community water than to sewer service; we also learned that new data collection processes are needed to update the estimates of access to water and sewer services in North Carolina.”


Gillings School of Global Public Health contact: David Pesci, director of communications, (919) 962-2600 or

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