Officials and engineers have warned for decades of a growing crisis with the aging systems that handle the billions of gallons of water flowing from toilets, tubs and washing machines across the country every day.
So when news broke ofthe untreated wastewater spill into the Potomac River in January, it wasn't a surprise to industry experts.
"When you think about the number of miles of wastewater pipes in the ground, and the age of them, and the fact that for many, many years they have been underfunded, it's not surprising that things like this can occur," said Darren Olson, a professional engineer whochairs the Committee on America's Infrastructurefor the American Society of Civil Engineers.
The societyproduces a "report card" of letter gradesfor each category of the nation's infrastructure every four years. Wastewater consistently earns a "D."
An estimated 3 to 10 million gallons of wastewater are spilled annually in the U.S., butno national data exists showing total discharges, USA TODAY previously reported.
While the federal government used to fund more than 60% of infrastructure improvements, Olson said today the federal funds cover less than 10%, and the costs for repairing, maintaining and upgrading wastewater systems are increasingly shifting to customers and hiking their utility bills. The average residential wastewater bill has nearly doubled since 2010, according to the civil engineers' "report card."
Potomac sewage spill called out by President Trump. See photos.
Aging wastewater systems drive up costs
While the average lifespan of a wastewater system is 40 to 50 years, many of the plants and pipes installed across the nation could be twice that old or more. In cities like Washington, D.C., for example, Olson said, wastewater systems were put in well over a century ago.
In some cases, those pipes may have been replaced, but in many cases, including Chicago, the pipes have not been replaced, he said. "They may have been repaired or maintained at times, but there are still pipes (sewers) in the ground throughout the United States that are well over a century old."
The pipes weren't built to handle the strain from rapidly growing populations and the enormous number of homes and businesses. Nor were they built to handle theincreasing intensity of rainfall ratesdriven by the warming climate that puts additional strain on systems, said Olson and Christine Kirchhoff, an engineer, associate professor and associate director of law, policy and engineering at Penn State.
"Infrastructure is aging, and local governments struggle to keep up with needed repair and replacement," Kirchhoff said. "Changing precipitation and temperature extremes puttremendous pressure on our systems designedfor the climate of the past."
For example, intense rain in Milwaukee in August 2025 led to5.14 billion gallons of untreated wastewaterfrom the city's combined sewer being discharged into nearby waterways and Lake Michigan, the Milwaukee Journal Sentinel reported. Another spill – 20,000 gallons –was reported in September 2025.
What happened on the Potomac River?
In Montgomery County, Maryland on Jan. 19, a 72" diameter section of a sewage pipeknown as the Potomac Interceptor collapsed.The pipe carries about 60 million gallons of wastewater daily from near Washington Dulles Airport in Virginia to a station that pumps it to an advanced wastewater treatment plant.
As a result of the collapse, more than 243 million gallons ofuntreated wastewater have flowed into the Potomac River, DC Water, the utility responsible for the system, reported on Feb. 6.
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The federal government built the 54-mile-long Potomac Interceptor roughly 60 years ago, when Lyndon B. Johnson was president and the entire population of the Washington, D.C. metro area was less than 3 million.
Since then the region's population has more than doubled, and like many other areas of the country, its aging sewer pipes are prime candidates for incidents like the collapse, which eventually ignited a war of words between MarylandGovernor Wes Moore and President Donald Trump.
The water utility already had planned a 10-year, $625 million rehabilitation of the line, said Sherri Lewis, a senior manager of communications for DC Water, in an email. Over five days, the utility built an emergency bypass to reroute the untreated wastewater around the break in the system, which reduced overflows at the site, and then continued working to enhance that bypass to begin emergency repairs on the damaged pipe.
The overflows havetriggered a number of recreational and shellfish harvesting advisoriesalong the Potomac.
On Friday, Jan. 20, the EPA announced the White House had assigned it to be the lead agency to coordinate among federal agencies and the utility in response to the spill, and to "ensure site clean-up activities are completed well before America250 festivities on the Potomac begin."
Wastewater by the numbers
Once the toilet flushes or the laundry is clean, wastewater disappears for most people and the problem is out of sight, until a large break or failure occurs.
People tend not to think about the network of sewers and water lines below ground when they're walking or driving, Olson said. The nation's wastewater systems include:
1.87 million – Miles of wastewater lines
3.3 – Number of failures per 100 miles of wastewater pipes annually
34 billion – Minimum amount of wastewater gallons treated daily
17,500 – Rough number of public wastewater treatment systems
15% – Number of wastewater treatment systems that have reached or exceeded capacity
"It's a massive amount of infrastructure and it requires a lot of investment to maintain it, to operate it and to improve it," Olson said. The civil engineers publish their report card to try to raise awareness of the need to invest in infrastructure before it fails, rather than after. The 2025 report card raised the letter grade for the nation's wastewater systems to a "D+."
Just like it's important to fix a leaky roof to avoid cascading effects all through your house, it's important to maintain these wastewater systems rather than deferring maintenance, he said. It's far less expensive to maintain than replace.
AnEnvironmental Protection Agency report to Congress in 2022points to the challenge, Kirchhoff said.
After tallying wastewater and stormwater system needs listed by communities and states for the next 20 years, the EPA concluded the total needed to upgrade wastewater systems exceeded $300 billion over the next 20 years.
When combined with water and stormwater needs, Olson said the total price tag exceeds $1 trillion.
Dinah Voyles Pulver covers climate change, disasters and the environment for USA TODAY. Reach her at dpulver@usatoday.com or @dinahvp on Bluesky or X or dinahvp.77 on Signal
This article originally appeared on USA TODAY:Potomac sewage spill just the beginning of USA's wastewater problems
