Chloride pollution of surface water and groundwater is an intractable problem. On one hand, sodium chloride (salt) is an important component of winter maintenance efforts that keep roads and other traveled surfaces free of snow and ice. On the other hand, many scientific studies have examined the potential risks to human health and natural resources associated with excess chloride in the environment, such as deteriorated ambient water quality, toxicity to aquatic and benthic organisms, adverse effects on vegetation, and even impacts to drinking water supplies.
Yet little of that scientific work has been directed toward developing legal and policy strategies to address the chloride issue. On the contrary, overapplication of salt has historically been the “safe strategy” to avoid liability in slip-and-fall cases in the absence of any coordinated policy approach.
To complicate matters, chloride is extremely difficult to remove using traditional water and wastewater treatment approaches, so use reduction appears to be the only effective management strategy. Given the public safety concerns, though, that approach is complex to say the least and must involve consideration of legal, environmental, and safety issues, among others.
Building on the proposed framework for the Southeastern Wisconsin Regional Planning Commission’s comprehensive Chloride Impact Study for the Southeastern Wisconsin Region, and working closely with Commission staff, Marquette Law School students Margaux Serrano (L ’24) and, prior to her graduation, Ivy Becker (L ’23) led the effort to develop a report examining a menu of responsive legal and policy options available to decision-makers in the Region. These include limiting slip-and-fall liability, relying on direct regulatory authority such as the Clean Water Act or corresponding state regulations and municipal ordinances, disseminating relevant information to stakeholders and the public, using alternatives to chloride where feasible, leveraging new policy strategies such as water quality trading, investigating integrated watershed management across jurisdictions, and leveraging economic measures and assistance.
Without question, these policy options will not all be appropriate in every context. After evaluating community-specific considerations, policy makers may choose one or more to reduce the problem of chloride transport to surface waters and groundwater. The report is not intended to suggest the elimination of chloride use in its most visible forms (winter maintenance and water softeners). Rather, it suggests that such use be optimized. Optimization carries “triple bottom line” benefits for the environment (in chloride reductions); for the economy (in cost savings on chloride expenditures and personnel hours); and for society (in improved public health).
Today’s post digs into the unique relationship between the two, given the recent announcement that Chicago has entered into a water supply agreement with the city of Joliet, approximately 35 miles to the southwest. Chicago will supply treated Lake Michigan water to Joliet for a century, beginning in 2030, at a cost estimated to approach $1 billion in today’s dollars. The Cleveland Plain Dealer called the deal a “stark warning” for the Great Lakes Compact. A USA Today column questioned, “How could Chicago [do that]?” The question likely invokes the Compact’s general prohibition on diversions outside the Great Lakes basin, with very limited exceptions. The answer lies in a 1967 amendment to a consent decree involving Illinois and other Great Lakes states, approved by the United States Supreme Court, that largely exempts Chicago from following the Compact’s rules.
The 1967 decree allots to Chicago (and several suburbs, via the Chicago water distribution system) a diversion volume of 3,200 cubic feet per second, or just over two billion gallons per day. The legal disputes that eventually resulted in the decree date back to Chicago’s reversal of the Chicago River, an engineering marvel resulting in no shortage of legal skirmishes. In a case argued before the Supreme Court in 1928 and decided a year later, Wisconsin, Michigan, and New York sued Illinois seeking to enjoin the Chicago diversion—then estimated at 8,500 cubic feet per second—because, they alleged, “the Chicago diversion had lowered the levels of [the Great Lakes and their connecting waterways] not less than six inches, to the serious injury of the complaining states.” The Court ultimately allowed the diversion to continue but capped its size to an amount that varied over decades of subsequent litigation until finally settling on 3,200 cfs in the 1967 decree.
Notably, the Court retains jurisdiction over the decree. From time to time a state has sought to reopen it. In 2010, for example, the Court denied Michigan’s motion to reopen the decree on the grounds that the diversion constituted a public nuisance by allowing the introduction of harmful aquatic invasive species into the Great Lakes.
The Compact’s default approach, a ban on diversions of Great Lakes water outside the Great Lakes basin, would prohibit the Chicago diversion. So there is no doubt that Illinois would not have agreed to the Compact without special carveout provisions protecting its rights to the Chicago diversion under the consent decree. The Compact does just that, in a lengthy section confirming that Great Lakes water use in Illinois is to be governed by the consent decree, not the Compact. In fact, to remove all doubt, the Compact actually prohibits Illinois from applying for diversions under its terms.
The precise terms of the Chicago-Joliet agreement are difficult to find, with the media reporting only the broad outlines of the deal. The Water Supply Agreement attached to the Chicago City Council’s approval provides that “Chicago shall deliver Water to Joliet on any day in an amount as requested by Joliet,” up to a “guaranteed maximum capacity” of 105 million gallons per day. That sounds like a lot of water—and it is—yet even at maximum capacity only accounts for about 0.05% of Chicago’s allocation under the consent decree.
Thus, there is little question that Chicago has the legal authority to sell water to Joliet. And even the maximum delivered volume is a drop in the bucket of Chicago’s allocation under the 1967 consent decree.
Yet the question remains whether it is good policy to sell water for economic development purposes. Some have suggested that as other parts of the country implement water use restrictions, the Great Lakes states should use water as a tool to attract new businesses and residents. Others argue that our abundant water supplies must be carefully stewarded. Finding the right middle ground will be challenging.
As for the Compact, the Joliet sale is perhaps foreboding, as the media coverage has suggested. But its immediate impact is limited to the amount of Chicago’s diversion. Greater difficulties await. At another recent Law School conference, this one commemorating the Compact’s tenth anniversary, former Wisconsin governor Jim Doyle suggested that the Compact’s greatest test would come when a signatory state faced a water crisis in a region outside the Great Lakes basin. Would the governor stick to the Compact and deny water to its own citizens, Doyle wondered? That is exactly the situation unfolding in Illinois, a Great Lakes state that is not governed by the Compact with respect to the Joliet crisis. But the implications for the other Great Lakes states – and the resulting concerns for the future – are unmistakable.
In June 2022, Wisconsin lawmakers approved a new drinking water standard for two of the most widely used per- and polyfluoroalkyl substances (PFAS). Prized for their water and stain-resistant properties, PFAS are found in an array of industry and consumer products, including firefighting foam, cosmetics, waterproof fabrics, nonstick cookware, and food containers. These human-made compounds are commonly referred to as “forever chemicals.” Resistant to chemical breakdown, they persist and accumulate in our bodies and environment. A growing body of scientific evidence links these chemicals to increased risk of certain cancers, high blood pressure, low birth rate, developmental delays, and harm to immune and reproductive systems.
Wisconsin’s latest regulatory action follows years of state and national debate about the risks of PFAS. The new drinking water standard sets the limit at 70 parts per trillion (ppt) for PFOA and PFOS, in line with a 2016 Health Advisory Level (HAL) issued by the US Environmental Protection Agency (EPA), but higher than the level recommended (20 ppt) by the state’s Department of Health Services and scientists working on the regulation.
There are currently no federal regulations for PFAS. However, just two days after the state legislature approved the standard, the EPA issued a new health advisory, reducing its previous recommended HALs to .004 ppt (PFOA) and .02 ppt (PFOS) in response to emerging evidence that even levels closer to zero are associated with adverse health effects. Because we currently don’t have the ability to detect PFAS at such low levels, any detectable amount would exceed those thresholds. The EPA is expected to issue a proposed National Primary Drinking Water Regulation for PFOA and PFOS later this year.
Wisconsin’s new drinking water standard requires that communities test public water systems for PFOA and PFOS. Those water systems that exceed the limit (for either of the chemicals or a combination of the two) will have to take corrective action. Public water utilities are also now required to issue a public notice for any amount over 20 ppt and disclose PFAS levels in their annual consumer confidence reports.
Voluntary tests of private wells conducted by the Department of Natural Resources (DNR) and others show that PFAS contamination is not just a concern for public water utilities. Wisconsin’s new standard, however, does not apply to groundwater. Nearly 30 percent of Wisconsin residents rely on private groundwater wells that are not connected to a public water system for their drinking water. Amidst growing concern about the risks of PFAS, the Natural Resources Board voted this past December to allow the DNR to move forward with developing separate standards for PFAS in groundwater.
Public understanding of PFAS risk and contamination will likely change as testing gets underway and more residents become aware of possible exposure. How concerned are Wisconsin residents about PFAS? Last June, we partnered with the Marquette Law School Poll (MLSP) to survey Wisconsin residents about their perceptions of PFAS risk and water quality in their communities. The survey was fielded just one week after the state legislature approved the drinking water standard and the EPA released its new health advisory. Wisconsin’s PFAS regulation took effect on August 1.
We found that many Wisconsin residents are worried about PFAS. Roughly 6 out of 10 respondents expressed some level of concern about PFAS contamination in their drinking water. Nearly twice as many said they were “very concerned” (31 percent) than said they were “not at all concerned” (18 percent). Five percent said they didn’t know.
We might expect some geographic variation in concern given differences in communities’ experiences. The city of Eau Claire, for example, shut down half of its wells because of PFAS contamination in 2021. There have been several other high-profile cases of PFAS contamination in the state, including in Madison and the Peshtigo and Marinette areas (Green Bay-Appleton media market). The Department of Natural Resources (DNR) lists over 120 sites with known PFAS contamination. Although there is some variation across Wisconsin’s media markets, none of the regional differences are statistically significant.
Several individual-level differences, however, are worth noting. Those getting their drinking water from public water systems expressed more concern about PFAS and the safety of their water supply than those on private wells. Consistent with previous research on gendered differences in risk perception, women expressed greater concern than men, all else equal. Wisconsin residents who reported paying attention to politics, whether there’s an election going on or not, were also more worried than those who reported paying little or no attention. And finally, we observe a partisan divide: Democrats and Independents expressed slightly more concern about PFAS than Republicans, all else equal. That said, we don’t want to overstate the difference: majorities of both Republicans (55%) and Democrats (72%) expressed concern.
We also asked respondents about their perceptions of safety of the drinking water supply in their community, a question that the MLSP has asked several times over the last few years. Because question wording was unchanged, we can compare responses over time. Concern in the state, on average, remains relatively flat, with roughly 4 out of 10 respondents saying they are “concerned” or “very concerned” about the safety of their water supply. There is a notable uptick in 2018, which is explained by increased concern in the WOW counties and Milwaukee County. There were several water-related issues in the news in this part of the state at the time, including the city of Waukesha’s approved plan to divert Lake Michigan water for public water supply (under an amended court order to comply with radium standards) and debates about how the city of Milwaukee was handling lead in drinking water. It’s possible that the rise in concern in 2018 reflected this high-profile news about water quality.
In our June 2022 poll, we found that Democrats were more concerned about PFAS than Republicans. Looking back at previous polls, however, we find that the partisan divide on water is recent and remains modest. In 2016 and 2018, the average opinions of Democrats and Republicans were statistically indistinguishable from one another. The partisan gap widens a bit in 2019, but the difference is not statistically significant. The figure below shows the unadjusted differences in opinion between Democrats and Republicans. Although the partisan gap is statistically significant in the June 2022 poll, it is substantively small, just four percentage points once we account for other factors, including socioeconomic status and whether the respondent lives in an urban, suburban, or rural community.
Previous research finds that framing—how an issue or problem is presented—can affect risk perceptions. We included a survey experiment to test whether geographic frames of reference affect Wisconsin residents’ opinions about water. We asked respondents whether water quality issues are mainly a problem in isolated parts of the state or affect residents statewide. We randomly assigned respondents to receive a slightly modified version of the question in which we varied the frame of reference. One third of respondents were assigned to a control group that received the question without any geographic referent. The other two-thirds of respondents received a version of the question that either referenced “Milwaukee” or “Eau Claire.”
A substantial majority of respondents said “statewide concern” across treatment conditions. However, there was a statistically significant increase in the percentage saying “statewide concern” among those who received the Eau Claire reference compared to those who either received the Milwaukee reference or the version of the question that did not name a place. Indeed, there was no difference in opinion between the Milwaukee and control conditions, suggesting that respondents think about water quality as an urban issue absent any additional information. As one resident told a reporter after learning his small rural community had tested for high levels of PFAS, “We didn’t have a whole lot of big city issues until now.” We find suggestive evidence that rural residents were the most sensitive to these geographic framing effects.
Governments around the world are working to increase community resiliency to natural and human-made disasters. Strategies include reducing vulnerabilities to environmental hazards, identifying effective mitigation technologies, educating the public about environmental risks, and crisis planning to reduce response times and economic losses. Community engagement is critical to these efforts. However, communicating PFAS risk is challenging. Wisconsin’s drinking water standard is new and does not yet apply to groundwater. A federal regulation, expected later this year, may set a lower PFAS limit. Testing will likely raise concerns about liability and cost. Who will pay for remediation remains uncertain. The Wisconsin Court of Appeals will soon hear a case on whether the state has the legal authority to enforce PFAS cleanups pursuant to its authority under the Wisconsin Spills Law. Scientific understanding of the adverse health impacts of PFAS is also evolving.
This research is part of a larger, two-year study of public understanding of PFAS in Wisconsin. New regulatory standards and testing requirements mean residents will hear about more instances of elevated levels and the need to mitigate and manage PFAS risks. In our first survey, conducted last June, we found that a large majority of Wisconsin residents are worried about PFAS contamination. In contrast to the deep partisan divides that typically define Wisconsin politics, water quality remains a bipartisan issue. Differences in concern, however, may inform communication strategies going forward. For example, concern is higher among those who pay close attention to politics, suggesting that more concerted efforts may be needed to engage less politically engaged residents. We will continue to survey Wisconsin residents about water quality issues in the coming year. One thing we will be looking at is whether the difference we observe between those on public water systems and those on private wells changes as testing in the state gets underway. We will also begin conducting focus groups to better understand local conditions and how risk information is framed and shared in communities across Wisconsin. With our colleagues in Biological Sciences, Economics, Education, Engineering, Law, and Political Science, our goal is to strengthen state and local resilience to possible PFAS contamination and other water-related hazards.
Dr. Jill McNew-Birren and Prof. David Strifling also contributed to this post.