An interdisciplinary team of East Carolina University (ECU) coastal scientists has been awarded rapid-response grant funding from the National Science Foundation (NSF) to study exposure to and existence of contamination in private drinking water wells following Hurricane Florence. The one-year study started in December 2018 and is focused in Duplin, Sampson and adjacent rural counties in eastern North Carolina. The study will gauge residents’ perception of risk to their water supply from before to after the storm, identify steps they have taken to protect themselves from this perceived risk, and use water quality data to determine the degree to which their perceived risk matches actual contamination. The study team includes Dr. Jake Hochard, principal investigator (PI) and natural resource economist at ECU and the Coastal Studies Institute (CSI); Ariane Peralta, microbial ecologist (BIO); Randall Etheridge, ecological engineer (ENG, Center for Sustainable Energy and Environmental Engineering); and Jamie Kruse, economist and Director of the ECU Center for Natural Hazard Research.
Duplin and Sampson counties are located in the rural coastal plain of NC, an area hit particularly hard by Hurricane Florence in September 2018. They also lead the nation in pork production (#1 and #2), have a large population using private septic systems prone to failure during flooding events, and are home to large populations of residents who rely on private wells for drinking water. These counties received over 20 inches of rainfall and extreme flooding during Hurricane Florence, raising concerns that hog waste lagoons breached by the flooding, failing septic systems or other sources of pollutants could be contaminating rural residents’ private wells and, therefore, residents’ primary drinking water. However, the extent to which residents are actually exposed to environmental water contaminants when they are present depends partly on how readily they perceive and take measures to protect themselves from the contamination (water filtration, water boiling, purchasing bottled water, etc.). Although water pollution following storm events like Florence is relatively frequently studied, residents’ perception of, and thus actual exposure to, this environmental risk—while no less important—is not. This study works to identify and fill this knowledge gap by leveraging recent pre-storm water quality data along with post-storm water sampling and thorough resident interviews to determine actual and perceived resident exposure to environmental contaminants.
“Water contamination itself is only part of the equation,” Dr. Hochard explains. “averting behavior, or the propensity of rural residents to take action to avoid exposure by using alternative water resources to well water, is the other part. Together, those two pieces make up exposure to contaminants – in this case, water pollution. We have a pretty good understanding of when and where water is contaminated, but we don’t do a very good job linking that to actual exposure.”
To address this, the research team intends to sample from 336 private wells that had water tests conducted within the year prior to Hurricane Florence to establish a low-risk baseline for the study group. These are the same sites they will use to assess post-storm impacts by testing for an array of microbial and nutrient contaminants, like fecal coliform and nitrates. To expand sampling coverage, the team will leverage ECU’s rural student body by recruiting undergraduate students from the study area counties to help identify additional residents amenable to sampling and interviews. To link this contamination to actual exposure, researchers will then need to determine what degree of risk these homeowners perceived, and how effectively they acted to protect themselves from it.
“From a public health perspective, we need to understand what measures are being taken to mitigate the risk [of groundwater contamination] by homeowners, which we currently have a very poor understanding of,” says Hochard.
To this end, researchers will interview homeowners within the study group from December 2018 to May 2019 to gauge whether they believe their water was contaminated by Hurricane Florence, having known before the storm that the water was determined to be safe. Second, if believed to be contaminated, they will determine how long the homeowners expect the contaminants to linger within their system before it becomes safe again. The interviewers will also record measures the homeowner has taken to protect the household from exposure to the perceived—although not necessarily confirmed—contamination.
Finally, water testing results will be communicated back to homeowners to identify the gap between risk they perceived and actually measured risk. This information enables researchers to assess whether that risk gap closes due to more information, which has the potential to influence public policy and disaster response decision-making.
“Very little is known about the landscape of public health risk in rural, often marginalized and underserved communities. This work will inform where to target public infrastructure investments. For example, should we expand water infrastructure into particularly vulnerable areas? It will also help us gauge whether there is a gap between perception of risk and actual risk. And if there is, what is the best policy measure to help close that gap? Communication of risk? Subsidized or cheap testing? This allows exploration of potential options to mediate exposure. If the state is willing to help reduce risk, studies like this one will help determine the best way to do it,” Hochard explains.
The project team envisions many extension opportunities from this work, including a partnership already underway with NC State and Virginia Tech to create a network of improved educational outreach materials for rural communities. Another aspect of the work, which overlaps with an EPA-funded project of the group’s, is a concerted effort to collect and map private drinking water well data across the region, including which aquifers they’re pulling from and other relevant characteristics. This knowledge would help disaster response teams focus their efforts and could also facilitate mutually beneficial transactions, like temporary well-sharing schemes, in the face of contamination caused by natural disasters in the future.
More information about this project and research group’s work can be found at their dedicated research website, https://www.ourncwater.org/.