Tides of Change
How UIC is Guarding Chicago’s Recreational Waters
Chicago’s iconic flag features two bold, blue stripes: one representing Lake Michigan and the other representing the Chicago River. Both bodies of water are central to the city’s identity. From the shores of Lake Michigan to the rivers that wind through its neighborhoods, water has always shaped the city’s growth, vitality, and well-being. At the University of Illinois Chicago School of Public Health (UIC SPH), researchers are leading the charge to ensure safe, equitable access to this essential resource while shaping the future of water safety nationwide.
What began as targeted work at local beaches has grown into a pioneering model for how data-driven science can inform public policy, protect communities, and even make history. Together, these efforts demonstrate how safeguarding water quality is about more than science—it is about meeting the evolving health challenges of our time.
Protecting the “Third Coast”
Lake Michigan, often called America’s “Third Coast,” is a freshwater expanse that rivals the Atlantic and Pacific in scale and significance. In the summer, its beaches become a vital resource for city residents seeking relief from the heat, recreation, and community.
But with heavy urban use comes heightened risk. Contaminants and bacteria can enter beach waters quickly, and traditional testing methods, taking 24-48 hours to deliver results, often failed to provide timely results. Officials were left with a dilemma: keep beaches open and risk exposure or close them preemptively and frustrate residents.
A decade ago, UIC researchers stepped in to change that. Working in collaboration with the Chicago Park District, they developed rapid-testing techniques that allowed for near-real-time water quality assessments. Instead of waiting days for lab results, officials could now make informed decisions within hours. This shift meant more accurate beach advisories, fewer unnecessary closures, and greater confidence for beachgoers in the safety of their summer outings.
The effort that goes into the testing process is invisible to most beach visitors, said project director Abhilasha Shrestha, a water quality researcher and research assistant professor in the Division of Environmental and Occupational Health Sciences.
“It didn’t make sense, because you were telling people to swim or not to swim based on data from the previous day,” Shrestha said. “With the qPCR method, we can provide same-morning results in three to four hours.”
By late morning, the Chicago Park District shares the results with flocks of beachgoing city-dwellers and visitors. Based on bacteria levels and other factors like wind and weather, flags raised on each beach indicate whether swimming in the lake is permitted (green), advised with caution (yellow) or banned altogether (red). Beach safety information and lab data are also available on the park district’s website.
“It’s not just about collecting data,” Shrestha explained. “It’s about making sure that data is meaningful and actionable for the people whose lives it affects.”
In its pilot year, the beach water testing project sampled five beaches, four days per week. After the UIC water testing team published a study on the benefit of rapid DNA-based beach-water testing, the university’s partnered water testing partnership with the Chicago Park District expanded. In 2016, the project grew to nine beaches, five days per week. The growing team tested 20 beaches, seven days per week from 2017 to 2019. Since then, the City of Evanston and the Winnetka Park District added 10 beaches, and erosion eliminated two in Chicago, bringing the total to 28.
Today, 17 UIC undergraduate and graduate students retrieve and test water samples from local beaches and report the results to the park districts every morning from Memorial Day to Labor Day.
No other U.S. cities test their water daily.
Making History on the Chicago River
UIC’s leadership in water testing has extended well beyond recreation. In September 2025, when local organizers with A Long Swim sought to launch a Chicago River swim this year, they turned to the same UIC team who had engendered public trust.
Chicago would be hosting a landmark event: organized swimming in the Chicago River for the first time in nearly a century. The river, once notorious for its pollution, had undergone decades of cleanup, but doubts about safety persisted.
“We were in the middle of our daily beach monitoring project when the organizers reached out in late June after a CBS news story on our partnership with the Chicago Park District aired,” Shrestha said.
Starting 19 days before the swim event, the water-testing team took samples regularly at eight sites along the course. The final test, a day before the swim, cleared the way for the historic return.
“We were excited because this was such a transformative and special event in Chicago,” said Shrestha, “But our approach stayed the same — use science to inform decisions, build community trust and promote healthy living.”
UIC’s testing made the celebration possible. By rigorously analyzing microbial risks, researchers provided the assurance organizers needed to safely allow swimmers into the river. The moment was symbolic, showcasing the city’s environmental progress, but it was also practical; without reliable data proving water safety, the event could not have happened.
Rising Challenges, Rising Innovation
Water safety is no longer just about preventing recreational illness but also monitoring how extreme weather can impact communities. Testing can help track patterns over time, revealing how factors like rainfall, runoff, and human activity influence water safety. The findings allow for proactive interventions and set new standards for how municipalities across the Great Lakes region could manage recreational waters.
The goal is not only to monitor risks but also to anticipate them. “Our methods provide a more responsive system—one that adapts to environmental changes and helps ensure the public’s right to safe recreation,” Shrestha noted.
UIC leads not only on water testing, but in multiple areas of environmental health. In partnership with the Chicago Department of Public Health (CDPH), UIC SPH is developing the Chicago Air Sensor Network to provide community-level air pollutant estimates across Chicago for residents to better understand the environmental conditions in their neighborhoods. Once fully deployed, Chicago is set to have the largest community air monitoring network in the world with nearly 280 sensors. And all of that data will be publicly available.
A defining strength of UIC’s environmental testing programs is their community-centered approach. Rather than keeping results in the lab, researchers work closely with city agencies, community groups, and the public to ensure that findings inform real-world decisions. This collaborative model builds trust, ensures transparency, and keeps equity at the forefront.
Student involvement is another key asset of UIC’s environmental testing programs. Since 2015, almost 90 students have helped protect Chicago residents through their work at UIC’s Water Microbiology Research Laboratory, currently run by Shrestha who started as a student researcher herself. Dr. Samuel Dorevitch, UIC professor of environmental and occupational health sciences, who helped start the water testing program passed the importance of mentorship.
“If I can have the same impact on my students that he had on me, I’d be thrilled,” Shrestha said. “Dr. Dorevitch is a big reason UIC is leader in testing public waterways.”
SPH graduate students William Kane and Joy Westercamp continued their summer water testing work with Shrestha for the Chicago River Swim.
“Abhilasha’s helped me grow as a researcher, and that’s something important to students,” Westercamp, a doctoral candidate who aims to be a professor, said of Shrestha. “She’s an incredible scientist who puts students first.”
Whether advising on beach closures or contributing to historic civic events, the school demonstrates how academic expertise can directly benefit public life.
Looking Forward
As UIC SPH celebrates its 55th anniversary, the legacy of water testing reflects the broader values of the school: science in service of the public good, innovation grounded in community needs, and a commitment to preparing for tomorrow’s challenges. From safeguarding summer afternoons on the beach to making history on the Chicago River, this work shows what is possible when rigorous research meets a city’s most essential resource.
“I hope this program can be an example to the rest of the U.S. and the world,” Shrestha said. “It’s all about building trust through science and improving public health, one beach day at a time.”