USGS researchers analyzed nearly three decades of data from more than 20,000 public and private wells nationwide and determined that between 75.3 percent and 84.9 percent of wells in Connecticut could contain corrosive groundwater.
If left untreated, corrosive groundwater can leach lead and other metals in pipes en route to the tap, raising health concerns for the estimated 871,000 state residents who rely on private wells as their primary source of drinking water.
In Connecticut, the state does not mandate or conduct testing of well water, instead relying on private well owners to maintain, test and treat their own wells. Many well owners are not aware of the risks of corrosion, environmental health activists say.
This map by the U.S. Geological Survey shows the prevalence of corrosive groundwater nationally. Most New England states have a very high prevalence.
Corrosive groundwater, or water with low pH and alkalinity levels, is a naturally occurring phenomenon dependent on geology, and it is not dangerous to consume by itself. The problem occurs when the water enters pipes. Lead was commonly used in plumbing fixtures throughout the first half of the 20th century, and Connecticut has some of the oldest housing stock in the country. When water with low pH and alkalinity levels interacts with lead, it triggers a chemical reaction that dissolves the metal and delivers traces to the tap. Warning signs include a metallic taste and bluish-green stains in the sink.
“Millions of Americans rely on private wells,” Kenneth Belitz, the scientist who led the study, said. “But the individual has to treat them, and it might be expensive, or they might not realize they need to do it.”
Water Monitoring, Testing
Public water supplies are monitored and protected by the U.S. Environmental Protection Agency (EPA) under the Safe Drinking Water Act, which sets standards for drinking water quality and works with state agencies to ensure drinking water safety. The EPA does not regulate private wells, and most states do not require testing.
Connecticut mandates testing only when a new well is constructed, and no database on testing is maintained. Rhode Island is the only New England state that collects and analyzes testing data on private wells.
The state Department of Public Health (DPH) told C-HIT that while the state does not have specific statistics on the prevalence of lead pipes in homes supplied by private wells, health officials encourage well owners to get their water tested by a state-certified laboratory. Lead exposure can cause a variety of health problems, the U.S. Centers for Disease Control and Prevention (CDC) reports. Children are especially vulnerable. In children, lead exposure can cause cognitive deficits, a loss in IQ points, speech and developmental delays and hyperactivity.
Ryan Tetrault, an environmental analyst for the DPH Private Well Program, said the program has held a number of outreach and education events in the past several years to provide information to private well owners on the importance of testing their private wells. Three years ago, the DPH received numerous complaints about high levels of arsenic and heavy metals in well water in several communities, including Weston, Stamford and Somers. At the time, DPH recommended that residents stop drinking their tap water, install remediation systems and test their well water yearly.
While well testing is affordable, treatment can be expensive. Bill Ainsworth, a veteran analyst for the Connecticut-based well-water service company Greco & Haines, says a standard battery of water-quality tests costs less than $200, but the bill for installing a chemical injection system or an acid neutralizer to treat corrosive groundwater can range from $1,500 to $2,000.
He estimated that the company tests about 5,000 wells per year, and that about half of them contain corrosive groundwater.
Environmental advocates say that the state should be doing more to protect well owners.
David Brown, the co-founder of the nonprofit Environment & Human Health, Inc., and a former CDC and DPH official, says it’s unrealistic to expect residents to regulate their own water supplies and suggested that local health departments do the job instead.
“I would think the state legislature might want to study this problem to see if the corrosivity of the water is producing exposures to lead and other metals. That would be a serious problem,” Brown said. “If you get a change, you’ll get it there [at the legislature], because the state’s environmental protection agency and the DPH don’t feel they have a responsibility for private wells. They’ll say you’re responsible for your own well.”
Ray Ough, 69, of Marlborough, says he and his wife have lived off well water for almost 40 years, and that well ownership not only lowers his utility bill but fits his do-it-yourself ethos. Ough says he gets his water tested “from time to time,” but conceded he wasn’t aware that corrosivity was a metric worth watching.
“When you have a well, you have some responsibility that goes along with that,” Ough said. “That’s just part of the homeowner experience.”
The USGS is planning more studies.
Corrosivity made national headlines when officials in Flint, Mich., failed to treat the city’s drinking water for corrosivity, creating a citywide public health crisis as lead leached into the public supply, and thousands of residents were exposed to the contamination.
Flint provided the motivation for a closer look at the risks posed by corrosive water in the absence of regulation on a broad scale, Belitz said.
The national study found that the Northeast, Southeast and Northwest had the largest percentage of wells with potentially corrosive groundwater.
In New England, Rhode Island, Massachusetts, Maine and New Hampshire also had a “very high” prevalence of corrosive groundwater, while Vermont was rated “high” prevalence.
Joseph Ayotte, a USGS scientist and groundwater expert for the New England Water Science Center, says Belitz’s study provides a starting point for more detailed and localized analyses.
In New England, he said, water in public supply wells tends to be more corrosive because it is drawn from the shallower glacial aquifer, while water in private wells tends to be less corrosive because it is drawn from the deeper bedrock aquifer, a phenomenon that could mitigate the risk of exposure for many private well owners.
“Now that we see there’s a potential for corrosive water…there is additional information that we could get by looking at this in more detail,” Ayotte said. He suggested further studies to identify which well types and aquifers are most susceptible, so that researchers can refine risk assessments.
