This story was produced in partnership with the University of Wisconsin-Madison’s Investigative Journalism class taught in the School of Journalism and Mass Communication.
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- Recent wildfires in Canada and northern Minnesota brought a wave of smoke to Wisconsin in July, raising concerns in Rock County similar to those in 2023, when Beloit was ranked the city with the worst air quality in the nation.
- Rock County faces above average asthma rates, and air pollution from wildfire smoke combined with emissions from existing polluters can worsen these health risks.
- The county relies on a particulate matter monitor in Rockford, Illinois, to track PM2.5 levels. Local advocates and community members are pushing for a regulatory monitor in Rock County, especially as industrial emissions increase.
Pablo Toral expected another successful summer field program at the Boundary Waters, continuing a tradition that has lasted close to 70 years. Instead, he found himself evacuating by canoe after wildfires forced his team to abandon the trip.
Students had already started arriving at the research station for the program’s mid-summer session. They were supposed to spend the next month doing hands-on field research, canoeing and camping. Then came the evacuation alert giving everyone 20 minutes to pack up and leave. Toral, the chair of environmental studies and political science at Beloit College, said it was clear conditions were unlikely to improve, leading organizers to cancel the rest of the program.
After driving through the night, Toral returned to Beloit, only to find that the wildfires had followed him in the form of thick smoke and unhealthy air quality.

Poor air quality is a serious concern for Beloit residents who worry about the emissions from nearby power plants and now wildfire smoke. Just three years ago, under similar wildfire concerns as this summer, the city was named the worst for air pollution in the United States.
Rock County also has above average asthma rates, making the poor air quality even more troubling for residents.
Cristine Rameker, the Wisconsin Department of Health Services’ asthma program manager, told Wisconsin Watch that the most recent estimate of asthma-related hospitalizations per 10,000 people in Rock County — between 2022 and 2024 — was 39% higher than the statewide average, with a rate of 3.2 per 10,000 people compared to 2.3.
During those years, asthma-related emergency department visits per capita in the county were 23% higher than the statewide average at 34.2 visits per 10,000 people compared with 27.8 statewide. For children ages zero through 17, the average asthma-related emergency department visit is about 9% higher than the state average.
The county ranked sixth-highest in the state for asthma hospitalizations and eighth-highest for emergency department visit rates between 2022 and 2024. Rock County is the ninth-largest county in the state in terms of population.
In 2024 alone, data shows there were 138 asthma-related emergency visits among children in Rock County, or one every two-and-a-half days.
Beloit School District data shows about 11% of students — 436 children — have asthma. Of those students, 110 have inhalers at school, while 326 do not have ready access to medication.

Brittany Keyes, clean air policy manager with Healthy Climate Wisconsin and former vice president of the Beloit City Council, recalled a moment last fall when she was riding on a bus in Waunakee with a group of third grade girls from Beloit, including her daughter, after the girls finished their first 5K for a “Girls on the Run” event.
She described how the third graders had been training for months together, and now they were laughing, exhausted and proud of their achievement on the ride home. Until one girl began struggling to breathe.
Keyes said a teacher was frantically searching through a bag for the girl’s inhaler — pulling one out, and then another.
“She takes out a bag — nope, it’s not hers. She takes another bag — nope, not hers, not hers, nope, not hers,” Keyes said. “There were six inhalers for a group of 22 girls. … That’s not normal, and it doesn’t have to be that way, right?”
No particulate sensors in Beloit
Fine particulate matter (PM2.5), a type of pollution that is a combination of solid and liquid particles in the air, is a key concern for residents worried about air quality and asthma rates.
Nick Mailloux, a postdoctoral research associate at the University of Wisconsin-Madison’s Center for Sustainability and the Global Environment, said a major reason why PM2.5 raises so much concern is its extremely small size — about 1/30th of the width of a human hair.
Particulate pollution comes from a range of different sources, including power plants, vehicle emissions and industrial facilities — which Keyes and Toral both noted can all be found in Beloit. Additionally, Mailloux noted that wildfires are increasingly becoming a source of PM2.5 across the United States.
“A particle of that size is small enough that it bypasses a lot of our natural defenses,” Mailloux said. “These are particles that are small enough where they can pass through your airways and into your lungs, where then they can get into your bloodstream and cause inflammation that leads to lots of different respiratory, cardiovascular and neurological health harms.”
PM2.5 can cause new or worsened heart and lung diseases, along with a list of health effects like coughing, shortness of breath, fatigue, asthma attacks and more.
While Keyes was still vice president of the Beloit City Council, she had read a 2021 report from Toral that found Rock County’s CO2 emissions increased by 325% between 2010 and 2019. After discovering that the emissions in her county were much higher than in counties like Dane and Winnebago, she contacted the Wisconsin Department of Natural Resources.

She learned the agency operated one monitor for ozone on the west side of Beloit, and only for six months out of the year. She said DNR officials recommended community sensors, such as PurpleAir monitors, if she wanted to start monitoring for herself.
PurpleAir makes sensors that actively monitor PM2.5, temperature, humidity and pressure, collecting air quality data and making it publicly accessible.
Keyes said different nonprofits across Beloit participated in a community project to install PurpleAir monitors in the city in late 2022, using a U.S. Environmental Protection Agency community sensor loan program. Early data raised concerns, but the DNR told her that only five months of data had been collected, which is far less than the three years needed to establish an annual standard, Keyes said. However, that’s all the EPA could lend them for their study.
The group had secured funding during their time with the EPA’s loan to install three monitors in Rock County, allowing for continuous monitoring with data collected every 10 minutes. Now, Keyes said they have been able to expand their monitoring network to more than 20 PurpleAir monitors in the county.
“Our effort has really built awareness, and even the Rock County Health Department went after a mini grant … and they were awarded it, and they got 10 sensors, and were able to put them up at schools around the county, so now it’s not just urban centers,” Keyes said. “It’s super cool if you look at PurpleAir now, how we have a better distributed geographical monitoring system.”
Then in early 2024, technology company and global leader in air quality monitoring IQAir contacted Healthy Climate Wisconsin with alarming news — Beloit was ranked the most polluted city in the United States in 2023. The company had pulled data from the PurpleAir monitors through 2023 to draw that conclusion.
What makes Beloit ‘pollution central’
Toral pointed to numerous factors — including an unusual amount of wildfire smoke from Canada that year, regional pollution from nearby cities such as Madison, Chicago and Milwaukee, as well as transportation emissions, nearby power plants and industrial activity — that all make Beloit “pollution central.”
He said bigger cities surrounding Beloit like Chicago, Milwaukee and Madison reported very high rates of pollution that summer exacerbated by the smoke. Toral noted all of those cities closely track their air pollution data. He pointed to the sensors Beloit has compared to other surrounding areas, saying through the sensors, Beloit was able to document where the smoke from the 2023 wildfires converged.
“Unusually, we got winds coming out of the northeast, and that brought back the smoke from the fires in Quebec,” Toral said. “Those are what led to the perfect storm — very active fire season, dry winter, slow snow precipitation in the winter, low precipitation in the spring, leading up to the fires lasting longer, being more aggressive.”
He said that while Beloit is small, its monitoring is on par with bigger cities like Chicago and Madison. So, while Beloit was ranked as most polluted, he said there’s also a lack of data from other cities in that area of the state and northern Illinois to officially confirm if it’s Beloit specifically.
“You don’t know how polluted you are until you test, and Beloit is very unusual in the sense that it’s a very small town that actually has very good air pollution sensors,” Toral said.
Keyes said the organizations involved in Healthy Climate Wisconsin’s air monitoring effort recognized the need for more coordinated action, so they formed the Stateline Clean Air Coalition — a group of organizations and community members who meet monthly to advocate for cleaner air and healthier communities.
She highlighted that for more than two years one of the coalition’s primary concerns had been to install a regulatory PM2.5 monitor in Rock County — specifically in Beloit. While Beloit has an ozone monitor, Keyes said it’s not ideally located and only operates for part of the year.
“(Ozone) is a harmful air pollutant, but not the most toxic. And what we’re really concerned about is particulate matter,” Keyes said.
Community members, health care professionals and advocacy groups also have shared their concerns with the DNR, urging a regulatory PM2.5 monitor in the area. Some argued that Beloit may have some of the highest PM2.5 in the state, with some estimates from advocacy groups and community sensors exceeding standards.
The DNR relies on data from a regulatory monitor in Rockford, Illinois, rather than direct measurements from Beloit. An agency spokesperson emphasized that Wisconsin meets the current PM2.5 standard of 9.0 micrograms per cubic meter, based on 2022-24 regulatory monitor data.
The DNR spokesperson cited the EPA, saying the three-year PM2.5 design value for Rockford from 2022 to 2024 was 8.3 micrograms per cubic meter, with an annual mean of 7.3 in 2024 — below the requirement for a regulatory-grade PM2.5 sensor.

Craig Czarnecki, the outreach coordinator of air management at the DNR, emphasized that regulatory monitors are used for official decision-making and produce the most reliable data, while community sensors like the PurpleAir monitors are better suited for general awareness.
“Data produced using low-cost sensors do not undergo the same rigorous quality assurance and are known to be biased high when compared with data produced by regulatory monitors. These limitations make low-cost sensors best suited for qualitative purposes such as making decisions on daily activities considering the current air quality,” Czarnecki said.
Despite ongoing requests from residents and advocates to install a regulatory-grade PM2.5 monitor in Beloit, particularly near known pollution sources and in heavily affected neighborhoods, the DNR has not committed to expanding its monitoring. The agency stated that the existing network meets federal requirements.
Czarnecki also noted the department lacks funding to expand monitoring beyond federally mandated levels.
Residents also raised concerns about the estimated 2.4 million metric tons of carbon dioxide emitted in Rock County in 2022, with about 2.1 million coming from power plants. The DNR spokesperson noted that CO2 is not regulated in the same way as pollutants such as ozone or particulate matter.
Keyes said concern over emissions increased as Beloit’s energy infrastructure began to expand. She pointed to Alliant Energy’s Riverside Energy Center and the additions of the West Riverside Energy Center, a 730 MW natural gas plant.
Toral said emissions data showed the Riverside Energy Center produced about 2.8 million tons of CO2 emissions the last year it was required to report in 2023, surpassing plants in higher-populated areas, which Toral said shows a “disproportionate concentration of pollutants in one single point.”
Although multiple coal plants used to be in the Rock County area, and burning coal was worse, Keyes noted that natural gas, primarily the burning of methane gas, is still very harmful for the environment and the health of communities.
“The fossil fuel industry has marketed very hard to make us feel like natural gas isn’t harmful. But it is. It is still a fossil fuel,” she said.
Alliant Energy has since proposed and been approved to build a liquified natural gas storage and processing facility in Rock County to meet growing demand. Taylor Adams, the senior communications specialist for Alliant Energy, said in a statement that the location was chosen for its proximity to infrastructure and customers and that the project will comply with environmental regulation.
“Rock County serves our largest concentration of natural gas customers in Wisconsin and is located near established pipeline corridors, making it a logical location for this type of infrastructure,” Adams said. “The proposed facility would incorporate multiple design features intended to control and minimize emissions.”
Adams said air quality impacts are currently under review by the DNR and will be available for public comment.
Who’s affected
Toral called the situation in Beloit, a low-income community of immigrants and people of color, “a case of environmental injustice.”
Toral noted the effects of pollution often fall most heavily on vulnerable populations, including children, older adults and people with preexisting conditions. He added that noise pollution can worsen health outcomes by increasing stress, disrupting sleep and weakening the immune system.
“If you basically are living close to traffic, a power plant, a factory, anything that generates noise — that really exacerbates people’s conditions,” Toral said. “That makes the body more vulnerable to then have to cope with the pollutants.”
Keyes highlighted that Beloit previously had lower emissions than Dane County, but as Madison was able to retire some of its natural gas and coal plants, the regional demand for electricity resulted in power plants — and emissions — expanding in Rock County.
Keyes’ daughter was one of 15 youth plaintiffs who filed a lawsuit against the Public Service Commission and state Legislature last summer over laws that prohibit the PSC from considering air pollution when reviewing permits for new power plants, along with a failure to protect the youth from climate change.
“Dane County has made progress, but the celebration of progress is really greenwashing the fact that we are suffering,” Keyes said.
New record, new norm
Air quality records were broken across Wisconsin July 16 as wildfire smoke from northern Minnesota and Canada was carried into the Great Lakes region by winds. Much of the state experienced hazardous air conditions, with Air Quality Index levels reaching their highest points in at least 16 years.
The smoke brought back memories of the 2023 wildfire season, when similar conditions covered much of the Midwest.

Toral said this year’s fires are following a similar pattern to 2023. He said because the Great Lakes form a basin, smoke tends to converge there, making Wisconsin “ground zero” for this contamination. He added that the current fire season is already very active, and while the fires were more severe three years ago, this year’s fires are closer to Wisconsin. However, he said it’s still too early to know whether this year’s fire season is going to be worse than 2023.
“We thought that the fire season we saw two years ago was one of a kind — was very unusual — and here it is again, two years later,” Toral said. “This is a very unusual pattern.”

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