Shimon Anisfeld, senior lecturer and research scientist, tours New Haven’s wastewater treatment plant with students from his water management class. Photographs by Ian Christmann
Safeguarding Our Drinking Water Supply
What’s in your drinking water? Research Scientist Shimon Anisfeld discusses how dangerous chemicals are an increasing threat and what can be done to protect the water coming from your tap.
When Shimon Anisfeld turns on his tap to get a glass of water, he often thinks about how far we’ve come in creating a safe water supply — and also about the emerging threats facing our water systems. Anisfeld, a senior lecturer and research scientist in water resources, who recently authored the book “Water Management: Prioritizing Justice and Sustainability,” says our drinking water is safer than ever, but we need to pay more attention to chemical contamination if we want to make sure it stays that way.
Q. In what ways has the safety of our drinking water supply improved since public water was first available in the 19th century, and why are chemicals now the chief concern?
Most of us take for granted that we can turn on our taps and get clean water 24 hours a day — yet this remarkable-but-unremarked infrastructure is a recent development, historically. America’s largest cities built their first public water systems roughly between 1800 and 1880, but those systems struggled at first to control recurrent epidemics of waterborne diseases, such as cholera and typhoid. We ultimately defeated those diseases through a twofold approach: building drinking water treatment plants to remove contaminants and protecting our rivers and reservoirs from being polluted in the first place.
Today, the primary threats to the safety of our drinking water come from chemical contaminants, including lead, nitrate, cyanotoxins, uranium, microplastics, disinfection by-products, and PFAS (per- and polyfluoroalkyl substances), often called forever chemicals. About 45% of the nation’s drinking water is estimated to contain PFAS, which have been linked to health issues, including increased risk of cancer and birth defects and developmental delays in children.
Q. What are some of the challenges in addressing the contamination?
We need to recognize that the quality of our drinking water is ultimately linked to the ways we use land and chemicals. Agricultural runoff drives nitrate and cyanotoxin contamination; mining contributes to arsenic and uranium problems; and continued production of persistent chemicals like plastics and PFAS means that they end up in our water supply. We can’t have clean drinking water without clean rivers, and we can’t have clean rivers unless we control pollution at the source, whether that source is a farm field, an abandoned mine, or PFAS-laden food packaging. This is hard to do!
Q. Why hasn’t the threat posed by PFAS been addressed sooner?
The fundamental challenge with addressing PFAS comes down to ubiquity and uncertainty. PFAS chemicals are ubiquitous in our society — in food packaging, firefighting foams, plastics, pesticides, and many other products — which increases the likelihood that they will end up in drinking water but also makes it hard for us to quickly find substitutes for all those uses. Add to that the scientific uncertainty around the health effects of different PFAS chemicals, and you have a recipe for inaction.
That said, the Biden EPA took the PFAS threat seriously; the agency issued drinking water standards for six PFAS chemicals and started addressing discharge to the environment. The Trump administration has already withdrawn the proposed discharge rules and is likely to back off from the drinking water standards as well. Without political will, the PFAS threat will continue to grow.
At the same time, many states have been taking action on PFAS. In 2022, Maine banned all land application of sewage sludge because of PFAS concerns. Currently, about two dozen states have enacted some form of PFAS limits in drinking water, although they differ in which chemicals are regulated, the levels at which they are regulated, and the type of limits.
Q. What needs to be done going forward to continue to make progress on eliminating dangerous chemical contaminants in our supply?
We need to work on protecting our watersheds and improving water treatment. Current drinking water treatment plants aren’t designed to remove high levels of nitrate or PFAS or other emerging contaminants, so we will need to invest significant funds to upgrade treatment plants where necessary. It is much cheaper and more effective to work on watershed protection: We need to strengthen regulations on agricultural runoff; rethink how we apply fertilizer, manure, and sewage sludge to farm fields; use green infrastructure to reduce the impacts of urban stormwater; and find substitutes for PFAS in our industrial and consumer products.
Q. What can individuals do to safeguard their drinking water?
Well, let me preface this by saying that bottled water is not safer than tap water. In fact, it’s less regulated — and much more expensive and environmentally damaging. It would really be a huge mistake for us to turn to private solutions like buying bottled water when we have a great public system that just needs a little love and attention now and then.
Residents can find out about their own water quality by reviewing their water company’s annual Consumer Confidence Report. At the same time, they can press for watershed protection at the state and local levels so that our public water supplies stay safe for many years to come. We all have a responsibility to make our drinking water as safe as possible.
