Editor’s note: This blog post summarizes and highlights key findings and recommendations from the Center’s new report, Private Wells in Virginia: Data Gaps and Public Health Concerns around Nitrate Contamination of Groundwater.
Widely available clean drinking water is something that we usually take for granted. One of the main reasons is that the vast majority of the U.S. population has access to public water systems, which are in charge of providing safe drinking water to their users. However, in many parts of the country, particularly rural communities, people rely on private wells for sourcing their drinking water, which broadly lack regulatory safeguards for public health and well-being. This is particularly striking in Virginia, where 22 percent of the population relies on water supplied by a private well, with the share of private well use reaching upwards of 80 percent of the population in the Commonwealth’s most rural counties.
Although federal and state laws require testing for and treatment of contaminated water in municipal water systems, broadly, no such legal protection exists for private wells. In Virginia, the burden of testing and treating private well water is placed on the property owner. This represents a major concern in the Commonwealth, where people sourcing their drinking water from private wells face exposure to potentially harmful levels of contaminants in their water supply.
One of the most common of these contaminants is nitrate: a colorless, odorless, and tasteless compound that is toxic when ingested in significant amounts. Although there are many pathways for nitrate to enter a water supply, the most common means of contamination comes from agricultural processes, typically those related to intensive application of fertilizers that leach into aquifers and travel into private well water sources.
As we explore in a new report, there is little comprehensive information on the distribution and severity of nitrate contamination in private well systems in Virginia. This is attributable to a lack of uniform testing and data collection protocols within state agencies, as well as the dissemination of information that would alert residents to the likelihood of a threat and motivate them to test their water supply. The report also highlights the impact of contamination across communities facing worse socioeconomic conditions and less access to healthcare, representing serious equity considerations in how residents are able to respond to water contamination.
Findings and Analysis
In researching this report, we conducted a study of almost 19,000 private wells across the Commonwealth. We partnered with the Virginia Polytechnic Institute and State University, in particular in its role with the Virginia Cooperative Extension, which carries out a testing support program, and the Southeast Rural Community Assistance Project, Inc., which supplied data spanning 14 years of private well sampling.
We structured our analysis around three main building blocks: the spatial distribution of contaminated wells, the spatial distribution of certain contributing factors (like animal feeding operations and preponderance of agricultural activities), and multiple socioeconomic and healthcare variables to understand the equity implications of nitrate contamination of private water wells.
The data shows that 1,128 wells (approximately 6 percent of the total sample) have nitrate levels above 5 mg/L, which studies have found to be potentially dangerous to human health. These numbers, which are already concerning, are an undercount of private well systems in the state with potentially or likely dangerous levels of nitrate contamination, highlighting that greater data collection, reporting, and access to data is necessary in Virginia to address public health risks tied to nitrate in private well water.
We also found important equity implications associated with nitrate contamination. There are hundreds of examples of high-nitrate wells located in tracts with high poverty and unemployment and where access to health care is difficult. These individuals are at a notorious disadvantage when it comes to bearing the costs of testing, remediating a contaminated well, or taking action once the consequences of ingesting contaminated water manifest.
Increasing both knowledge of sources of contamination and improving mitigation practices through funded best management practices will serve to reduce the risk of and severity of contamination. For example, we obtained data for animal feeding operations via a request to the Virginia Department of Environmental Quality regarding currently operating facilities and found a strong overlap between their location, predicted levels of underground nitrate, and a concentration of elevated rates of nitrate in private wells.
Recommendations
The report includes several important recommendations at the state and federal levels. Critically, we recommend that Virginia should address the lack of information and the financial burden on private well owners, both for testing and remediation in case of contamination.
For example, expanding the Virginia Cooperative Extension Program’s well testing program, as well as providing a compensation program to offset costs for well water testing directly through the Virginia Department of Health (VDH), would reduce barriers to residents to conduct testing. The state should also require testing for nitrate (and other priority contaminants) at the time of well drilling and that all testing data be collected and stored by VDH’s Office of Drinking Water while also facilitating the submission of future testing results. This should be paired with a comprehensive public-facing database.
This regulatory landscape not only affects property owners, but renters as well, who have comparatively less agency to conduct testing or remediation. The state should require nitrate testing to be conducted by owners of properties that source their water from a private well and who lease their property to tenants. Testing should be conducted prior to the start of leasing the property and every three years subsequent.
Given the inequitable implications of nitrate contamination in private wells, the state should pay special attention to this issue and increase funding streams, particularly grant funding to private well owners, to facilitate remediation and ensure safe drinking water when contamination is present, with special focus on low- and moderate-income households.
The U.S. Environmental Protection Agency should re-evaluate nitrate’s safety levels based on current scientific evidence that expands on nitrate’s potential harmful effects, as well as increasing funding opportunities for private water systems to assist populations, who are often socioeconomically disadvantaged, to remediate their source of drinking water.
By expanding data collection, analysis, and dissemination and taking common sense actions to protect and empower residents, Virginia can meaningfully improve health outcomes for those who rely on private wells for their drinking water.
