10/25/2024

How Aging Water Systems Are Pushing Sewage Into U.S. Homes

A Black man stands on an empty dirt road looking down at water bubbling from a drain, on an overcast winter day
Walter Byrd checks on an overflowing sewer grate next to his home in Cahokia Heights in 2020. Byrd’s home has regularly flooded with raw sewage in recent years. Credit: Carolina Hidalgo, St. Louis Public Radio

Walter Byrd remembers the first time sewage came bubbling out of his toilet like it was yesterday.

“It was just pumping up through there,” Byrd says. “One of the bathrooms was so full of waste, at least 4 inches high in there. It smelled just like a hog pen.”

He sopped up the murky, foul-smelling water and doused the floor with bleach. But the sewage kept coming. On rainy days, it overflowed from drainage ditches into his yard, carrying wads of toilet paper and human waste.

The eight-bedroom home in Cahokia Heights, Illinois, had been a source of pride for Byrd when he first built it in 1996. He spent a lot of time outside, caring for his vegetable garden and watching wildlife wander through the backyard. But trying to stop the sewage backups quickly became his main focus, consuming countless hours and thousands of dollars of his savings.

“It was a dream house, until the floods came,” says Byrd, now 67. “That house broke me down.”

Byrd’s is one of hundreds of homes in this small community that has experienced sewage backups for years. The southern Illinois city, which sits just across the Mississippi River from St. Louis, has struggled with declining population sizes in recent decades. The majority of residents are Black and over 40% live in poverty.

At a town hall meeting in 2021, Illinois Senator Tammy Duckworth said that communities of color, like Cahokia Heights, have had to “bear the burden” of sewage backups and other environmental issues for far too long.

“No one should be forced to live with a public health crisis in their backyard, no matter their zip code, the color of their skin or how much money they make,” Duckworth said.

How Sewage Ends Up In Homes

In cities across the United States, complex networks of underground pipes carry drinking water, sewage, and stormwater from place to place. In all, millions of miles of pipes crisscross the country, including 800,000 miles of public sewer lines. The average age of these water and sewer pipes is nearly 50 years, but in some cities, pipes are more than a century old.

Though the issue is particularly severe in Cahokia Heights, residential sewage backups are common across the country. The causes vary, depending on how each city’s sewer and stormwater systems are designed. In Cahokia Heights, persistent sewage backups can be traced to outdated, poorly maintained systems that are unable to handle current demand.

The city’s stormwater and sewer systems were originally designed to be separate. The low-lying region relies on a network of drainage ditches and pumps to funnel stormwater to nearby waterways, including the Mississippi River. But the pumps, some up to 70 years old, struggle to keep up during intense rainstorms. Meanwhile, many stormwater pipes are cracked or blocked with sludge and tree roots.

When the pumps and pipes can’t keep up with rainfall, stormwater pools on the streets, says Shawn Sullivan, who works with the St. Louis District of the Army Corps of Engineers. From there, it can enter sanitary sewers through manholes, creating a “mixing and blending” between the two systems, he says. The influx of stormwater sends water in the sewage system “back upstream” through pipes, and into people’s homes through bathtub drains, toilets, and kitchen sinks.

A basement floor covered in sewage.
Sewage backups have become part of daily life for some residents of Cahokia Heights, Illinois. During rainstorms, waste flows up through drains, toilets, and sinks, leaving behind a thick layer of sludge, as shown here in a resident’s basement in October 2021. Credit: Brian Munoz, St. Louis Public Radio

Climate change is exacerbating the issue, driving more intense and frequent rainstorms that inundate the city. During heavy rain events, fast-moving floodwaters have turned streets into rivers and even trapped residents in their homes. Emergency crews rescued dozens of people from their homes by boat in 2015, after 4 feet of floodwater inundated one neighborhood.

But civil rights attorney Kalila Jackson says the root cause of sewer backups in Cahokia Heights is prolonged infrastructure neglect, not climate change. Jackson works with Equity Legal Services, a nonprofit representing some residents affected by sewage backups in two ongoing lawsuits against the city.

“This was completely preventable,” Jackson says. “This is not a situation where people moved into a flood zone. They didn’t move into the path of the Mississippi. This is what happens after decade, after decade, after decade of someone failing to maintain a system.”


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Residents dealing with sewage backups may also face health risks, as human waste carries bacteria, viruses and parasites. One ongoing study has found parasites in stool samples collected from residents, including tapeworms and protozoa. Some residents have also tested positive for Helicobacter pylori, a common bacterium that infects the stomach lining. In some cases, it can cause painful gut inflammation, ulcers, and even certain stomach cancers, says Dr. Theresa Gildner, an assistant professor of biological anthropology at Washington University in St. Louis who is leading the study.

Pathogens and parasites like these tend to be more common in developing countries, says Gildner, and are often underappreciated by US researchers and medical professionals. But infections can have health consequences, she adds, especially in lower-income areas.

“It is the most vulnerable who experience this and it can really compound existing issues, like not having access to healthcare, not having access to nutritious food or clean drinking water,” Gildner says.

Sewage Overflows By Design

Deteriorating infrastructure is not the only cause of sewage overflows.

Many US cities have combined sewer systems, where stormwater and sewage flow through a single set of pipes. When it rains, stormwater flows into the system through storm drains. To prevent the system from backing up into basements and streets during storms, there are specific points where pipes can release a mixture of sewage and stormwater into waterways, in what’s known as a combined sewer overflow.

There are more than 700 communities in the US with combined sewer systems, mostly in the Northeast and Midwest, including New York City, Chicago, and St. Louis. When introduced in the 1850s, these systems were hailed as a major improvement over the open ditches and cesspools of human waste that were common at the time and caused frequent disease outbreaks. Eventually, newer cities started building completely separate sewage and stormwater systems.

Sewage pouring into a body of water running through a town, discoloring the water.
A combination of stormwater and sewage overflows into Cincinnati’s Mill Creek from a combined sewer overflow point during heavy rain on May 7, 2024. Credit: Becca Costello, WVXU

But cities that still have combined sewer systems are facing a new challenge: Their capacity can no longer handle current demand. In some places, urban population growth and higher water usage have increased the amount of water going into sewer systems. Moreover, intense rainstorms can rapidly overwhelm combined sewer systems. Sewer overflows that were meant to function as release valves in times of extreme flooding are now sending sewage into rivers and creeks more regularly. According to a 2004 estimate from the Environmental Protection Agency, combined sewer systems release 850 billion gallons of raw sewage into waterways every year. (Many cities and towns have reduced their sewage overflows since then, but the EPA has not released updated data.)

A Path Forward

Some cities, like Minneapolis, have worked to separate the sewage and stormwater systems into different pipes. But that approach can be very expensive. Officials in other cities, like Cincinnati, are working to add capacity to their system instead, building storage tanks to temporarily hold the excess sewage and stormwater until the treatment plant can handle it.

Another solution is “green infrastructure,” in which stormwater is directed into waterways through mostly natural means instead of via pipes and pumps. The Lick Run Greenway in Cincinnati has been lauded as an example of “daylighting” a stream that had been buried in a pipe over a century ago. The stream now handles most of the stormwater from the surrounding low-income neighborhood that once faced persistent sewer backups and combined sewer overflows.

A body of water running through a town.
The Lick Run Greenway in Cincinnati carries stormwater to the Mill Creek. Previously, heavy rain would mix with sewage in the city’s combined sewer system, frequently overflowing into waterways. Credit: Becca Costello, WVXU

Other US cities are updating their stormwater and sewer infrastructure, fixing broken pipes and pumps. In Cahokia Heights, crews are working to shore up miles of pipes using a technique known as cured-in-place-pipelining. Workers feed resin-soaked fabric and fiberglass tubes into broken pipes and blast hot steam inside, hardening the resin and creating a pipe within a pipe. Though considerably cheaper and faster than digging up and replacing pipes, the installation process has been linked to health problems for residents and workers elsewhere in the US.

Nearly $50 million in state and federal funding has been set aside for the work, which could take at least a decade to complete. Whether the funding will be enough to fully fix the city’s sewage issues remains unclear. Cahokia Heights officials did not make anyone available for an interview or respond to specific questions for this story.

After grappling with sewage backups for years, residents are impatient for the issue to be fixed.

Walter Byrd’s home has had a growing list of issues related to the sewage backups, from a persistent mold problem to rotting floorboards. He estimates he’s spent tens of thousands of dollars over the years on repairs, replacing drywall and flooring, tearing out bathrooms, rerouting pipes, and replacing flood-damaged appliances.

Byrd hopes the government will buy out his home, so he can afford to move somewhere else and have something to leave to his grandkids one day. “We’re just tired of this,” he says. “We ain’t young no more. Do something for us now, because we ain’t gonna be here forever.”


This article was written by Shahla Farzan. Additional reporting by Becca Costello.


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Segment Guests

Shahla Farzan

Shahla Farzan is a science journalist, PhD ecologist, and editor with American Public Media, where she helps produce science podcasts for kids. She loves showcasing the many weird and wonderful aspects of science—and encouraging young, curious thinkers to question and explore the world around them.

Becca Costello

Becca Costello is a reporter at WVXU in Cincinnati, Ohio.

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About Shahla Farzan

Shahla Farzan is a science journalist, PhD ecologist, and editor with American Public Media, where she helps produce science podcasts for kids. She loves showcasing the many weird and wonderful aspects of science—and encouraging young, curious thinkers to question and explore the world around them.

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