On this planet, water is practically everywhere. Yet worldwide, less than 0.01% of that water could be considered safe and accessible for drinking. Lately, that figure has declined by a tiny margin of a percentage, but that decline has had great significance for the people of Flint, MI.
Through a complex set of circumstances, lead—one of the most legendary toxins of the periodic table—contaminated the drinking water of tens of thousands of Flint residents. The case of Flint, and the devastating impact of lead contamination on the people of that city, illustrates how fragile water supplies can be even for one of the most industrialized countries on Earth. Commenters in the media and experts elsewhere have attributed the disaster to an array of causes ranging from ill-considered policy decisions and inattention, to regulatory requirements, to aging infrastructure and the pervasive effects of poverty. At its center, the tragedy flowed from a decision to switch the city’s drinking water source from the Detroit City water system and its source, Lake Huron, to the Flint River.
Streams of Ions
Drawing on the Flint River for the city’s drinking water supply set off a fateful chain of reactions, the most potent of which was triggered through the water’s interaction with metallic components of the distribution system. Flint water was corrosive.
Ions seeking equilibrium, flowing through the Flint River, gave its waters a potential toward corrosivity, right down to the level of the individual household. According to reports, Flint River water, introduced into a distribution system that had customarily delivered water of a less corrosive nature, quickly consumed the protective coating of scale previously deposited on the interior of the metallic distribution piping system. Analysts believe that once the protective coatings of scale had dissolved away, lead contained in the piping and joints down to the household level became subject to corrosion. Lead leached into the water in citizens’ homes. Drinking water from the tap presented the risk of poisoning.
David Bellinger, professor of neurology at Harvard Medical School and professor in the Department of Environmental Health at the Harvard School of Public Health, noted in the New England Journal of Medicine that “corrosion-control treatments required by the Environmental Protection Agency’s Lead and Copper Rule were not followed, while the addition of ferric chloride to reduce the formation of trihalomethanes from organic matter increased the corrosivity of the Flint River water.”
The water reaching consumers was “19 times as corrosive as it had been when the source was Lake Huron.” The more corrosive water is, the more readily it can dissolve metals such as lead. In six of nine city wards, the water in 20 to 32% of the homes had a lead concentration above 15 micrograms (μg) per liter, a concentration that triggers remedial action under the Lead and Copper Rule.
Mona Hanna-Attisha, a Flint-area physician studying the health impact of the Flint lead contamination crisis, reported that among children in Flint, the incidence of blood lead concentrations above the reference value of 5 μg per deciliter rose from 2.4%, to 4.9% between 2013 and 2015.
Although experts say the tragedy in Flint could have been averted had officials adhered to well-established protocols in the EPA Lead and Copper Rule, for all the allegations of human error, missteps, and spurious motivations, many also believe Flint represents but a peek into what could go wrong almost anywhere. For months, during and after the debacle in Michigan, multiple headlines all around the United States have agonized over the question: “Could Flint Happen Here?”
The potential for source water-related catastrophes is a category of risk that goes beyond corrosion and lead alone. In 2014 in Toledo, OH, an overabundance of algae in source water precipitated a crisis when nutrient loads contributed to a severe toxic algal bloom. Cyanotoxins released by the algae forced the city to shut down its water system for days. Charleston, WV’s water system found itself inundated with toxic runoff from a coal mining discharge. In that incident from January 9, 2014, an estimated 10,000 gallons of an industrial chemical, 4-Methylcyclohexanemethanol (MCHM), spilled into the Elk River, contaminating the water and precipitating a “Do Not Use” order from the governor’s office. More than 350 area residents sought emergency medical care, suffering symptoms related to exposure to the chemical. The headlines bear an eerie repetitiveness as communities and water suppliers are caught unaware of threats to their drinking water resources.
Changing Times
Steve Via, regulatory affairs director for the American Water Works Association (AWWA), believes unfortunate incidents like those that occurred in Flint, Toledo, and Charleston should serve to keep attention focused on a resource that many citizens have increasingly taken for granted.
Although Via says “very rarely” do water utilities make the drastic decision, as Flint did, to abruptly switch drinking water sources from one body of water to another, he concedes, “Every water system is trying to make sure it can meet demand. Typically, when you reach 80% of capacity for any given water source, you’re going to start looking for alternatives.” Although in the case of Flint, the issue that drove the switch was cost rather than capacity, change may be coming.
Along with development, large-scale agricultural practices, and industrial uses, climate change is exerting increasing pressure on water sources and aquifers, in many cases accelerating their rate of depletion beyond sustainable levels. Considering these ongoing trends, Via notes, “You do find some systems who find groundwater no longer meets their needs, so they’ve begun looking at blending surface water as a source to meet their needs.”
He believes that when the need for changing water sources does confront suppliers, data will be one of the vital keys to making the right choices in sources, treatment, and distribution. He says there is no better time to begin preparing than the present.
“Right now,” he says, “there’s an acute focus on the topic, so managers of drinking water systems need to ask themselves if they feel confident they have the data on hand to make the right decisions. If you have an alternative water source that is stable, you can start to test the potential impacts that using this water source can have. You can do a tabletop analysis. You can get some information from other utilities that use the same aquifers, and you may actually need to do some studies. The main thing is getting as robust a data set as you can to understand the characteristics of the water they will rely upon, currently and in the future.”
At an operational level, Jim Taft, the executive director of the Association of State Drinking Water Administrators, recommends a multi-barrier approach to managing the risks from source to tap. Number one on his list is protecting the source “using all means possible.” The second barrier that must be in place to ensure a safe supply of drinking water is to make sure the treatment facility is producing water that meets federal requirements.
The third part of the puzzle, Taft says, “is to pay particular attention to things that happen in the distribution system. There are a couple of contaminants to watch out for; the most prominent lately is lead. If the water is corrosive at all, and you have old housing stock with lead service lines, you have this potential for what happened in Flint.” Even water treatment processes employed to combat separate water-quality issues such as pathogens can increase the potential for corrosivity.
Taft observes that suppliers must provide “adequate disinfection to make sure that microbes don’t regrow.” However, when chlorine, ozone, or disinfectants are added, if there is trace organic material present, then over the long time period it takes for the water to pass through the distribution lines, “there is the danger that you can get the formation of disinfectant byproducts,” he says. “The key is creating the right balance between disinfection and disinfection byproducts and insuring that the water is not corrosive. Data at every step is important.”
Above all, Via says, when it comes to providing safe drinking water, “Treatment alone is not what you want to rely on. You want to have a robust awareness of what’s going on further up in the watershed and do what you can to protect the watershed.”
He says the process becomes a matter of “managing unknown risks and uncertainty. The more you can stay ahead of contaminants and not put something in the water that may potentially become problematic, or that we may find is problematic a decade from now, the easier it becomes to manage the treatment cost, the easier it becomes on the community’s confidence in their water supply and your understanding of its safety.”
National News and Forecasts
The National Water Quality Assessment (NAWQA) has been the main federal program providing data on a wide variety of water-quality measures in streams, rivers, and the most important aquifers used for drinking water, says Gary Rowe, chief scientist for NAWQA. In its third decade, the $60 million a year program’s goals are “to assess current conditions and related ecosystem conditions and how they are changing over time, and evaluate the factors influencing the change.”
As Rowe explains, the assessment does not directly monitor the quality of water going into drinking water treatment systems, but rather, it supports long-term monitoring sites all across the country that sample six to 24 times a year for nutrient loads and other types of constituents. He notes that in instances where these sites are located near drinking water intakes, they can provide valuable tools for alerting authorities to variations in the characteristics of source water. However, the overall assessments, spanning entire aquifers, are equally vital to understanding the long-term outlook for source waters. NAWQA documents changes in source water quality nationally in publications such as “Groundwater Quality in Principal Aquifers,” released in 2015, and a range of US Geological Survey (USGS) circulars on water quality.
Rowe says NAWQA also provides analysis on how conditions might change in the future. “One way to do this is by looking at the past to predict the future,” he says. Also, according to Rowe, the USGS is able to evaluate records going back to the early 1900s. With regard to nutrients, for example, USGS data over the 20th century shows changes in nutrient loading, evident in large increases in nutrients in waterways, coinciding with the advent of commercial fertilizers and row cropping starting in the 1940s. Rowe says data show that by the 1980s, large increases in nitrates and nitrites had leveled off with nutrient loads remaining at elevated levels. He notes that changes in nutrient loads can have major impacts on water quality—for example, by fueling the growth of toxic algae, or by supporting the development of biological communities that alter the pH of source waters or other chemical and biological characteristics that could affect its suitability as drinking water.
The data NAWQA presents include not just material of academic interest, but often directly actionable information. From tracking pesticides in streams, for instance, NAWQA data reveal clear patterns. “We see pre-emergent herbicide application residuals that roll out with the spring first-flush,” says Rowe. With access to such information, managers of utilities downstream of agricultural districts often consider adding an activated carbon treatment to pull out organic chemicals that might be present in source water during the spring flush.
Separate Channels
For Taft, the challenge of providing quality drinking water weaves through numerous channels. He says protecting sources depends upon “both mandatory and voluntary measures, most of which fall outside the Safe Drinking Water Act.” He believes being able to guarantee safe and reliable drinking water at an affordable cost will take a group effort, which could grow to involve nearly everyone in a given watershed.
Via agrees, and advocates for collaboration, but he also notes that “There’s a fair amount of siloing that goes on” that can make it difficult to keep the channels of communication clear between the various agencies involved in water policy. “The stormwater people have a goal out ahead of them that is driven by the Clean Water Act, and the Safe Drinking Water act serves as the focus of the water works people.” The two mandates don’t always perfectly match up.
Stew Thornley, health educator for drinking water with the Minnesota Department of Health, says he understands how these competing priorities can lead to conflict between departments in the field over how to best fulfill their respective missions. Thornley recalls a historical episode related to him by senior management during his early days with the Minnesota Department of Health. Firefighters found themselves battling a blaze in a developed area of northern Minnesota. As Thornley recounts the event, the Department of Health wanted to see the fire suppressed as soon as feasible, to minimize dispersal of fumes and smoke over the community. The Department of Health lobbied for firefighters to deploy a specialized fire-suppressant foam to douse the flames as quickly as possible. However, their request was met with an opposing view from the Department of the Environment, which advised caution in deploying the suppressant, pointing out that residuals from the foam might eventually seep into the groundwater and possibly, in the long-term, have a negative effect on drinking water quality.
“It’s a healthy thing to have this tension,” says Thornley, and the key to protecting source water is transforming that tension into partnerships focused on a unified long-term and ultimately mutually beneficial goal. Although there are exceptions, such as the example above, he says, “What helps the Health Department generally helps pollution control. Protecting the environment and protecting health really go together.”
Via says that lately he can see the silos between various departments gradually beginning to break down. He cites as an example areas of the northern United States where he has witnessed a new focus on collaboration between water works, environmental agencies, and even highway departments, driven by their mutual concerns about the accumulation of road deicing salts in the environment. In many cases these agencies have coalesced around a mutual goal of reducing the application of the salts to lessen the potential of salt-bearing runoff percolating into aquifers or wells that supply drinking water to their constituents.
Building Networks
Because activities likely to be effective in source water protection follow the contour of watersheds rather than political or administrative boundaries, Taft says, achieving buy-in from a range of jurisdictions becomes extremely important. He suggests that downstream communities find ways to articulate the benefits that upstream communities can realize through participation in a source water protection program, even if their drinking water is drawn from a different source. “The question is, what can you offer?”
Taft believes the Source Water Collaborative (SWC) represents an ideal forum promoting cooperation over issues related to road salts and other threats to source waters. According to him, the SWC outlines a series of helpful protocols for productive engagement between the various agencies involved in water-related policy to assist them in balancing their individual priorities and meeting their mutual goals.
Established in 2006, the SWC is composed of 26 national organizations including the AWWA, Clean Water Action, the American Planning Association, and government agencies such as US Department of Agriculture, united to work on source protection from nearly every conceivable angle. In addition to this national perspective, the SWC offers advice and support to local groups who wish to organize regional, state, and local collaborations for source water protection.
“If you’re a water utility, you really need to know what your source water is. If you’re getting contaminated source water, that’s going to present massive challenges to you in terms of achieving adequate treatment, and indeed, some things are not treated very well in a conventional water treatment facility unless it’s been augmented to ensure that it’s addressing some exotic or emerging contaminants that we don’t know about,” says Taft.
Thornley adds, “The task is to identify the sources of contamination and which way that contamination might flow, and to work to manage the sources.”
Thornley believes partnerships can also have day-to-day operational value. “If the pollution control agency is aware of a spill, they let us know and we can go out and see what kind of impact that might have on drinking water in that area and see what has to be done.” On the other hand, he says, “Things could happen where we are all of a sudden finding something that’s a little strange to be finding in the water, we can inform the pollution control agency, then they can go take a close look.”
Taft recommends that every water utility have a source water protection plan, an idea the SWC also advocates. “None of us can do it all individually. That same thing is true at the local level. If you have an agricultural or industrial or municipal user upstream, you need to know who they are; you need to be in touch with them. You need to have monitoring, and you need to have notification procedures, so that if something is spilled they let you know.” In addition, he believes citizens need to be in touch with their political representatives to make sure they “have the best protection possible for their watershed.”
A New Roadmap
In February 2016, EPA released a new online mapping tool designed to help communities protect and manage drinking water sources. It provides the public, water system operators, state programs, and federal agencies with critical information about their drinking water sources and the conditions that might affect them.
The Drinking Water Mapping Application to Protect Source Waters (DWMAPS) mapping tool and application allows users to learn about their watersheds and understand more about their water suppliers. DWMAPS can direct users to ways they can get involved in protecting drinking water sources in their communities.
EPA recommends that utilities and state drinking water program managers also use DWMAPS along with their own state and local data to help guide them in planning for source protection activities. Although DWMAPS does not display the actual locations of public water system facility intakes, it does contain a wide variety of data useful to protection of drinking water sources. Specifically, DWMAPS helps users to identify potential sources of contamination in user-defined locations, find data to support source water assessments and plans to manage potential sources of contamination, and evaluate accidental spills and releases. DWMAPS also integrates drinking water protection activities with other environmental programs at the federal, state, and local levels. DWMAPS can provide users with information to update source water assessments and prioritize source water protection in any location or watershed in the country.
Multiple Goals
“When you’re looking at successful source water protection programs, they succeed by meeting multiple goals,” says Via. “It’s going to be about finding a dual benefit, so not only is the downstream community benefitting, but there is something in it for the upstream community, too.”
He adds, “There are instances where it’s going to be easier than others. For example, when you have drinking water sources that are linked to federal lands, there’s already a good level of collaboration with federal land managers, particularly folks like the Forest Service, in terms of protecting water supplies. A new development in that is dealing with wildfires, so it’s an existing relationship that’s taken another turn.” Another excellent example of cooperation across jurisdictions can be seen in the work of SWC members such as the Ohio River Valley Water Sanitation Commission (ORSANCO). “They’ve been a fixture in the Ohio River for 30 years, and they do a good job of taking information from one community and illustrating what the impact is for the next.”
No Simple Solutions
Flint has restored its connection with the Detroit water system and is once again sourcing its drinking water from Lake Huron. In a move conceived to restore confidence in the safety of the city’s water, Rick Snyder, the governor of Michigan, made a promise to personally drink water from the Flint water supply for 30 days.
Responding further to the crisis in Michigan, the Flint Water Advisory Task Force, an official panel appointed by the governor in the wake of the emergency, has proposed replacing all lead piping service lines in the city’s water distribution system. Meanwhile, the governor, endorsing the recommendations of University of Virginia researchers, has advanced the idea of doing the same for 2,000 water distribution systems throughout the entire state of Michigan. While the price tag for such an infrastructure overhaul would run into the multi-billion dollar range—without a ready source of funding—it would still resolve only one dimension of the problem Flint faces.
Researchers have pointed out that the lead contamination issues seen in Flint were exacerbated by lead piping and solder within antiquated piping in residents’ homes. Lead contamination arising from exposure to corrosive water in household lead piping would not be addressed by municipal infrastructure improvements.
“There are always new problems; some are manmade, some are natural, and some are a combination of both,” says Rowe. “We have examples of large-scale human drivers affecting water quality—for example, irrigation out in the West. When you start applying water to fields that haven’t been irrigated for millennia, things that accumulate in the soil, like nitrates, start moving, and they can interact and that can change the chemistry of the underlying aquifer system.”
In California’s Central Valley, he notes, “We’ve seen uranium show up in groundwater at high levels that previously was not there. It turns out it’s tied back to the irrigation going on with all the agriculture; it’s affecting the geochemistry and releasing the naturally occurring uranium in the system.
“The challenge for all of us working in water is to try and educate folks,” adds Rowe. “It is complex information that can be hard to communicate. Unlike streamflow, people don’t see an immediacy with water quality. If your lake turns green, it will get your attention on the nutrient load.”
