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University Gazette

The University of North Carolina at Chapel Hill

Beyond city limits

Jacqueline MacDonald Gibson and Frank Stillo tested the well water of 57 homes just outside of city limits in Wake County. They discovered that 65 percent tested positive for at least one of three microbial contaminants.

Why do some neighborhoods lack access to municipal services? And how does this affect families? UNC public health researchers found answers testing well water in Wake County.

Frank Stillo grew up in New Jersey drinking water from his family’s nearly 200-year-old private well.

He spent most of his life believing well water is both cheaper and superior to municipal water systems before he found out, as a doctoral student in the Gillings School of Global Public Health, that he was wrong.

Between 2002 and 2009, more than 62,000 of New Jersey’s wells were tested, and one out of every eight contained arsenic, radionuclides, mercury, nitrates – contaminants that can arise from natural geologic deposits, failed septic tanks, fertilizers and pesticides, landfill seepage and urban sprawl.

These contaminants pose higher risks in private wells than in regulated community water systems that must monitor their water and treat it to remove contaminants once they are detected.

“I always thought having well water was so great,” Stillo admitted. “But if you spend five minutes researching the topic, you quickly realize that might not be the case.”

Drinking dirty water can lead to gastrointestinal illness, reproductive problems, neurological disorders and much more – and it’s up to well owners to monitor the safety of their own supply.

Private wells in North Carolina

The risk of drinking contaminated water is particularly high in North Carolina, with the third-highest population proportion (35 percent) relying on private wells. The level of use of private wells in North Carolina is more than double the 14 percent of U.S. households that rely on private wells, according to the to the U.S. Geological Survey.In 2014, Stillo and his adviser, Jacqueline MacDonald Gibson, an associate professor of environmental sciences and engineering in the Gillings school, tested the well water of 57 homes in Wake County just outside city limits.

Sixty-five percent of households tested positive for at least one of three microbial contaminants – a problem that Stillo and MacDonald Gibson linked to increased risk of emergency department visits for acute gastrointestinal illness.

Connecting such households to nearby municipal water lines could help decrease this threat.

“Raleigh has an outstanding, well-funded municipal system,” MacDonald Gibson stressed. “People who have access to municipal water can be sure they’re getting really good water protected under the Safe Drinking Water Act. But these excluded communities along the edge of the city limits don’t have that protection.”

Understanding underbounding

Another root cause for this public health risk is a form of residential segregation called “underbounding,” which occurs when cities and towns grow around communities of color, keeping them just outside of municipal boundaries, MacDonald Gibson said.

The practice dates back to the post-Civil War era when emancipated slaves were given land on the outskirts of town. It resumed a century later when many rural black migrants settled just outside the borders of towns and within small pockets of cities. Some of this geographical isolation is attributed to the manipulation of town limits.

As a result of the practice, these neighborhoods lack access to municipal services such as police and fire protection, solid waste collection – and city water. They also have little political voice in land-use and permitting decisions.

“These actions keep white voting power in the government,” said MacDonald Gibson, who first learned about underbounding when Jeff Engel became the state health director in 2009. “He said one of his top priorities was to figure out the water quality and health implications for underbounded communities within the state. But there wasn’t any public information on where these neighborhoods were located.”

Mapping Wake County’s wells

The research team focused its study on Wake County because of the completed data sets for access to municipal water supplies available in property tax records.

Using this information, she and her team of students mapped the locations of these small, fragmented communities. Then, they sent out a letter describing the study to more than 1,000 residents with wells.

Over the course of six months in 2014, MacDonald Gibson, Stillo and research assistants received funding to collect three samples from the first 57 homes. Approximately two-thirds of the water systems were contaminated.

Because so many different kinds of waterborne pathogens exist, researchers use indicators to test for water contamination. MacDonald Gibson and Stillo used three: coliform bacteria, E. coli, and enterococci.

Coliform bacteria, the weakest indicator, exists in water, soil and on plants, so its presence doesn’t necessarily mean contamination. E. coli, a type of coliform bacteria, is a stronger indicator that suggests fecal contamination – it’s commonly found in the guts of animals and humans. Enterococci is the most dangerous and can lead to infections within the urinary and digestive tracts, blood and brain.

Contaminated wells and septic systems decrease property values – and if the county health department learns that they’re not up to code, they may condemn the property unless the owner can pay to repair the well or replace the septic system.

“When a septic system in a tight, urban community fails, it affects everyone in that community,” Stillo said.

The average cost of installing a new system is $5,000 – “an expense many can’t afford,” MacDonald Gibson added.

Another challenge is that few people test their well water for possible problems. “My students conducted in-depth interviews with about 20 households and found that only one gets his well water tested on a regular basis,” she said.

Stillo, who is also an environmental specialist with UNC Environment, Health and Safety, recently received a 2017 GEAB Impact Award from the Graduate School for this research.

“We may be a global public health department, but this is happening in our backyard,” he said. “It’s becoming clear that it’s something we need to worry about, and I hope that, maybe, we can be a voice for these people.”

Testing for lead

Now, MacDonald Gibson and Stillo are testing for prevalence of lead in these water systems. So far, they’ve collected water samples from 29 Wake County homes – eight of which have elevated lead levels.

To continue testing for lead, Gibson wants to partner with RTI. With additional funding, she and Stillo can collect water samples from more houses in Wake County, as well as blood samples from the people in these neighborhoods, particularly children.

“The World Health Organization has this calculation called disability-adjusted life year,” Stillo said. “If a child was at a certain IQ level and lead exposure brings them down to a mental disability level, then there’s a cost for that. It helps stakeholders understand that, yes, there’s an up-front cost to infrastructure extension, but there’s also a cost of doing nothing.”