Dangerous nitrate pollution has contaminated the groundwater that supplies private drinking water wells and public water utilities in several agricultural regions across the United States, posing a significant threat to people's health. A new report from the Center for Progressive Reform (CPR) indicates that this problem has reached Maryland's Lower Eastern Shore, an area that's home to hundreds of concentrated animal feeding operations (CAFOs) and millions of chickens.
Nitrates are a compound formed when nitrogen, largely from manure and fertilizer, breaks down. When manure is overapplied or mismanaged, rainfall or irrigation can cause nitrates to trickle down through soil into groundwater resources. Tainted Tap: Nitrate Pollution, Factory Farms, and Drinking Water in Maryland and Beyond notes that a single poultry CAFO raising 82,000 laying hens can produce 2,800 tons of manure a year, more than three times the amount produced by the Maryland Zoo in Baltimore each year.
Though private well testing data is limited, our investigation found indicators that pollution associated with CAFOs is contaminating the groundwater that residents rely on for their drinking water. Since nitrates are colorless, tasteless, and odorless, most families don't even know that it's in their water. We examined currently available data in Wicomico, Worcester, and Somerset counties and found:
- Wicomico and Worcester counties have detected nitrates at levels exceeding the U.S. Environmental Protection Agency’s (EPA) safe drinking water threshold in roughly one out of every 25 private drinking water wells.
- An additional one out of 14 wells in those two counties had nitrate concentrations just below EPA’s threshold, which public health research suggests may be hazardous to people’s health.
- Nitrate contamination is also evident in public water utilities. Overall, at least 61,000 residents in the two counties are being or may be exposed to nitrate contamination from public and private water sources.
- Somerset County also provided a small sample of well testing records that did not demonstrate contamination, but the records were at times incomplete and unreadable.
Drinking water contaminated with nitrates can contribute to a host of health problems, including certain types of cancers, pregnancy complications, and blue baby syndrome, a condition that can be fatal to infants. Cancer (especially colorectal cancer) and infant mortality rates in Lower Eastern Shore counties are among the highest in Maryland. Research shows these conditions are associated with consuming nitrates in drinking water.
These findings are troubling on their own, but they raise larger questions. What don't we know about nitrate contamination in private wells and public water sources on the Lower Eastern Shore? Are health hazards lurking just beneath the surface, unknown and unaddressed because of a lack of testing and transparency? Are these risks disproportionately impacting communities of color and low-income families? Additional investigation and far more testing are needed to determine the extent of nitrate pollution and its impacts in this region.
Kathy Phillips, Executive Director of the Assateague Coastal Trust and Lower Eastern Shore resident, commented on the issue in her community. "On the Lower Eastern Shore, most of us rely on individual wells for our drinking water, and there is little to no testing required of these wells, nor do our local health agencies expend enough effort to educate the public about the quality of our drinking water. Decades-long land application of animal manure and sludge to our agriculture fields has tainted the groundwater and our wells. Our communities have a right to water that is drinkable and greater effort must be made to reduce the impacts of industrial agriculture on our water, land, and air."
Nitrate pollution from mountains of manure and fertilizer doesn't just impact drinking water sources in Maryland's Lower Eastern Shore. 21 percent of private wells across the United States have reported nitrate contamination, and if periodic well water quality testing was required in every state, that percentage would likely be a lot higher.
The federal Safe Drinking Water Act doesn't protect private well owners from nitrates or other types of pollution, and Maryland and numerous other states aren't doing enough to protect their residents from nitrates in their drinking water. In a nationwide comparison of protective policies and programs for private wells, we found that Maryland ranked among the five states with the fewest policies. No state in the country requires periodic testing of private well water, and only a handful offer lower-cost test kits for families who want to test their water on a regular basis.
Unfortunately, nitrates cannot be removed from water through boiling or chemical disinfection and require costlier treatment systems like reverse osmosis. Well owners in Maryland and beyond are generally expected to take the safety of their drinking water into their own hands, even though many do not have the financial or technical means to do so. This results in disparate impacts on lower-income families who may not be able to afford testing or household water treatment systems.
To better protect Marylanders from nitrates, we offer a set of recommendations, including the following:
- Establish safe drinking water standards for private wells and smaller community systems that are not covered by the federal Safe Drinking Water Act.
- Require the Maryland Department of Health or Maryland Department of the Environment to implement a well compensation program that helps cover the costs of well water testing, sampling, and analysis, along with any needed remediation or replacement due to contaminated drinking water, prioritizing funding for low-income residents.
- Require property owners wishing to sell their homes to test well water quality within six months of sale and disclose well water test results to potential buyers.
- Require landlords to test well water quality on leased property every three to five years and inform tenants of the results.
- Publish all water quality testing results for private wells on a public online portal operated by state and local health departments and require regular information-sharing between relevant state and local agencies and state-approved laboratories.