Months after Cahokia Heights residents found E. coli in water from their kitchen taps, the community's water providers have been cited by the Illinois Environmental Protection Agency for deficient disinfection methods.
When the Illinois EPA conducted testing over three days last week, water inside residents' homes from both the city and private water company Illinois American Water had low levels of chlorine, a common disinfectant utilities use to kill germs as water travels through pipes to homes.
The state's regulatory standard is 1.0 milligram per liter. The deficient results in Cahokia Heights ranged from 0.03 to 0.64, according to documents provided by the Illinois EPA.
Community-organized testing from June to December also found low chlorine levels in tap water, in addition to E. coli in some samples.
"This is a health hazard to our community," longtime resident Yvette Lyles said at a news conference Wednesday.
Residents have been raising concerns about their drinking water for years because of longstanding infrastructure problems in the community. Heavy rain can force sewers to overflow onto streets and flood into residents' yards and homes.
The issue is particularly pronounced where Lyles lives in the former city of Centreville, which is served by Illinois American Water.
Residents organized the group Centreville Citizens for Change to advocate for solutions.
Some have stopped drinking from the tap, instead keeping stacks of bottled water on hand. They say they don't trust the water in their homes because at times it is brown, cloudy, has visible particles in it and smells or tastes foul.
The water providers contend that their own testing outside of homes shows the drinking water meets regulatory standards.
Lawyers Nicole Nelson, Kalila Jackson and Kennedy Moehrs Gardner and community organizer Maliaka Hill from the nonprofit Equity Legal Services lead the ongoing community water testing program with resident participants and volunteers.
The attorneys and residents worked with the Illinois EPA to arrange the state agency's initial testing inside 21 homes from Aug. 4-5. The state followed up Aug. 7 with confirmatory testing at any homes with deficient results.
Lawyers from Equity Legal Services also represent Cahokia Heights residents in federal litigation against city officials seeking infrastructure fixes and compensation for their property damage.
About a dozen residents, the lawyers and other community testing partners gathered Wednesday to draw attention to the Illinois EPA's test results. Their news conference was in the Piat Place neighborhood of the former Centreville, where residents say sewage backups have been happening for decades. Centreville merged with Alorton and Cahokia to become Cahokia Heights in 2021.
Eight of the chlorine deficient samples came from Illinois American's water and one came from the city's water, according to Gardner. She said the Illinois EPA collected a total of 19 water samples from homes served by Illinois American and two water samples from homes served by the city.
The water from one home served by Illinois American also tested positive for total coliforms, a group of bacteria common in the environment, according to residents' lawyers. Regulators say they are generally not harmful, but their presence signals a potential problem with equipment or treatment systems.
The Illinois EPA said another sampling at the home days later did not detect bacteria a second time.
In response to a request for comment, Illinois American Water provided a statement saying the company's water testing has not shown any issues.
"Illinois American Water is committed to providing clean, safe and reliable drinking water to the Cahokia Heights homes and businesses we serve," the company said in the statement. "The ongoing testing that our company performs in Cahokia Heights confirms that the drinking water supplied by Illinois American Water continues to meet chlorine residual requirements and bacterial water quality standards set by state and federal regulators.
"Illinois American Water takes regulatory compliance seriously and we are cooperating fully with the Illinois Environmental Protection Agency as this matter undergoes agency review."
Cahokia Heights Mayor Curtis McCall Sr. deferred comment to the city's attorney, Erica Spitzig, who did not immediately respond to a request for comment.
In previous statements, the city has also said that its testing shows the water is in compliance with regulations.
McCall previously suggested residents with troubling results from the community testing could have a problem with the water lines on their properties because of the age of their homes, which Equity Legal Services disputes.
The U.S. Environmental Protection Agency previously required increased water monitoring in both of Cahokia Heights' water systems over concerns about possible contamination from sewage on the ground if the water pipes below lost pressure from a leak or break.
Gardner said the low-pressure conditions that contribute to contamination happen frequently in the community.
The federal agency released Illinois American Water from the 2021 mandate in 2023 after determining that it met the terms of the order. It released the city from the extra monitoring on Aug. 7, the same day that the state agency issued its citations, according to Jackson.
Inside the disinfectant findings
In the Aug. 7 violation notice, the Illinois EPA said Illinois American Water failed to maintain minimum chlorine levels in the following locations:
- 200-400 blocks of North 62nd Street
- 7000-7300 blocks of Edna Street
- 400-500 blocks of North 73rd Street
- 4700-5000 blocks of Lake Drive
- 0-200 blocks of North 80th Street
- 400-450 blocks of North 82nd Street
The city of Cahokia Heights was cited for inadequate chlorine in the 5800-6000 blocks of Mitchell Lane, according to its violation notice.
The state is asking the utilities to ensure their chlorination equipment is operating properly and investigate their distribution system hydraulics.
Neither water system has detected E. coli in treated drinking water, public records from the past 15 years show. None of the Illinois EPA's samples tested positive for E. coli either.
Before collecting water, the lawyers said the Illinois EPA required residents to remove any faucet aerator, disinfect the faucet with alcohol and flush their system by running the tap for five minutes, which draws fresh water from the water main into the home's pipes. But Jackson noted that residents are likely not taking those steps on a daily basis when they use tap water.
"How many people run the tap water for five minutes before they make a bottle for their baby?" Jackson said. "… Understand that these tests were not done under real life conditions, so our concern is, if done under real life conditions, what is the true picture?"
Jackson said the community testing team believes the Illinois EPA will find E. coli if it continues looking. The agency has so far committed to additional testing in September, according to Jackson.
"What we have always said is that the conditions create opportunities," Jackson said. "Having low chlorine in the system creates opportunities for bacteria to come into people's homes."
The community-led testing collects water with faucet aerators in place, both before and after flushing the system.
It found E. coli in eight of the 118 samples collected from 23 homes over seven months last year.
After the community's initial round of testing ended in December, a second round began in February, which remains ongoing.
Residents share health concerns
Residents like Branden Harlen worry that the drinking water could be affecting their health.
"Whenever someone has a stomach ache, a rash or even throat problems — every time something happens with our bodies, we have to consider the water," Harlen said during the news conference.
Another resident, Ashley Taylor, said in a statement that she tries to refrain from using tap water to make babies' bottles because of health concerns.
Taylor said her home's chlorine levels were below the regulatory requirement when the Illinois EPA tested her water last week.
Jeanette Green, a resident and Centreville Citizens for Change member, said she will not drink tap water or give it to her dog. She prefers using bottled water to bathe, too.
Like some other residents, Green is frustrated that she pays for water she is not comfortable using.
"I would like for the water to be fixed, or they lower our water bill — something," Green said Wednesday.
Lyles, who is the Centreville Citizens for Change vice president, believes the drinking water has made her sick multiple times.
She said she has been diagnosed with a bacterial infection from Helicobacter pylori as many as five times in the 32 years she has lived in her Cahokia Heights home.
H. pylori is thought to spread through contact with feces or contaminated food or water. It infects the stomach after it is ingested. In severe infections, it can cause ulcers. Some research has also linked long-term H. pylori infection to a higher risk of developing gastrointestinal cancer.
An ongoing health study, separate from the community and state water testing, is tracking H. pylori infections and intestinal inflammation among Cahokia Heights residents. The research is led by Washington University in St. Louis and the University of Colorado Colorado Springs.
Researchers want to understand how flooding with sewage-contaminated water might be affecting the residents' health.
The health study has found about 90 active H. pylori infections from 2022 to 2025 with sample sizes between 42 and 98 adults and some overlap in participants each year.
Lyles said she was hospitalized in 2018 for symptoms from H. pylori and had surgery more recently because of another infection from the bacteria.
"I am so sick and tired of being treated for H. pylori," she said. "... I do not use the water, and I would encourage everybody — tell your neighbors — to get on these water testing lists to make sure you know what's coming through your pipes."
Resident Davona Connors said she was also diagnosed with H. pylori infection when she sought treatment because of pain around 2023. Doctors told her that her stomach was inflamed.
"That was miserable," Connors said.
Connors moved to Cahokia Heights from Belleville in 2019, not knowing about the community's issues with flooding and sewage. She believes the conditions led to her bacterial infection.
When it rains, water pools in front of her driveway, and she said it smells like a bathroom.
Many residents, including Connors, feel the Illinois EPA's testing results validate community drinking water concerns that some officials have dismissed over the years.
"Nobody's gonna keep telling the same lie," Connors said.
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