This story also ran on WAMU. It can be republished for free.
On a bright October day, high schoolers from Francis L. Cardozo Education Campus piled into a boat on the Anacostia River in Washington, D.C. Most had never been on the water before.
Their guide, Trey Sherard of the Anacostia Riverkeeper, started the tour with a well-rehearsed safety talk. The nonprofit advocates for the protection of the river.
A boy with tousled black hair casually dipped his fingers in the water.
“Don’t touch it!” Sherard yelled.
Why was Sherard being so stern? Was it dangerously cold? Were there biting fish?
Because of the sewage.
“We get less sewage than we used to. Sewage is a code word for what?” Sherard asked the teenagers.
“Poop!” one student piped up.
“Human poop,” Sherard said. “Notice I didn’t say we get none. I said we get what? Less.”
Tours like this are designed to get young people interested in the river’s ecology, but it’s a fine line to tread — interacting with the water can make people sick. Because of the health risks, swimming hasn’t been legal in the Anacostia for more than half a century. The polluted water can cause gastrointestinal and respiratory illnesses, as well as eye, nose, and skin infections.
The river is the cleanest it’s been in years, according to environmental experts, but they still advise you not to take a dip in the Anacostia — not yet, at least.
About 40 million people in the U.S. live in a community with a combined sewer system, where wastewater and stormwater flow through the same pipes. When pipe capacities are reached after heavy rains, the overflow sends raw wastewater into the rivers instead of to a treatment plant.
Federal regulations, including sections of the Clean Water Act, require municipalities such as Washington to reduce at least 85% of this pollution or face steep fines.
To achieve compliance, Washington launched a $2.6 billion infrastructure project in 2011. DC Water’s Clean Rivers Project will eventually build multiple miles-long underground storage basins to capture stormwater and wastewater and pump it to treatment plants once heavy rains have subsided.
The Anacostia tunnel is the first of these storage basins to be completed. It can collect 190 million gallons of bacteria-laden wastewater for later treatment, said Moussa Wone, vice president of the Clean Rivers Project.
Climate change is causing more intense rainstorms in Washington, so even after construction is complete in 2030, Wone said, untreated stormwater will be discharged into the river, though much less frequently.
“On the Anacostia, we’re going to be reducing the frequency of overflows from 82 to two in an average year,” Wone said.
But while the Anacostia sewershed covers 176 square miles, he noted, only 17% is in Washington.
“The other 83% is outside the district,” Wone said. “We can do our part, but everybody else has to do their part also.”
Upstream in Maryland’s Montgomery and Prince George’s counties, miles of sewer lines are in the process of being upgraded to divert raw sewage to a treatment plant instead of the river.
The data shows that poop is a problem for river health — but knowing what kind of poop it is matters. Scientists monitor E. coli to indicate the presence of feces in river water, but since the bacteria live in the guts of most warm-blooded animals, the source is difficult to determine.
“Is it human feces? Or is it deer? Is it gulls’? Is it dogs’?” said Amy Sapkota, a professor of environmental and occupational health at the University of Maryland.
Bacterial levels can fluctuate across the river even without rainstorms. An Anacostia Riverkeeper report found that in 2023 just three of nine sites sampled along the Washington portion of the watershed had consistently low E. coli levels throughout the summer season.
Sapkota is heading a new bacterial monitoring program measuring the amount of E. coli that different animal species deposit along the river.
The team uses microbial source tracking to analyze samples of river water taken from different locations each month by volunteers. The molecular approach enables scientists to target specific gene sequences associated with fecal bacteria and determine whether the bacteria come from humans or wildlife. Microbial source tracking also measures fecal pollution levels by source.
“We can quantify the levels of different bacterial targets that may be coming from a human fecal source or an animal fecal source,” Sapkota said.
Her team expects to have preliminary results this year.
The health risk to humans from river water will never be zero, Sapkota said, but based on her team’s research, smart city planning and retooled infrastructure could lessen the level of harmful bacteria in the water.
“Let’s say that we’re finding that actually there’s a lot of deer fecal signatures in our results,” Sapkota said. “Maybe this points to the fact that we need more green buffers along the river that can help prevent fecal contaminants from wildlife from entering the river during stormwater events.”
Washington is hoping to recoup some of the cost of building green spaces and other river cleanup. In January, the office of D.C. Attorney General Brian Schwalb filed a lawsuit seeking unspecified damages from the federal government over decades of alleged pollution of the Anacostia River.
Brenda Lee Richardson, coordinator of the Anacostia Parks & Community Collaborative, said the efforts to cut down on trash and sewage are paying off. She sees a river on the mend, with more plant and animal life sprouting up.
“The ecosystem seems a lot greener,” she said. “There’s stuff in the river now that wasn’t there before.”
But any changes to the waterfront need to be done with residents of both sides of the river in mind, she said.
“We want there to be some sense of equity as it relates to who has access,” she said. “When I look at who is recreating, it’s not people who look like me.”
Richardson has lived for 40 years in Ward 8 — a predominantly Black area on the east side of the river whose residents are generally less affluent than those on the west side. She and her neighbors don’t consider the Anacostia a place to get out and play, she said.
As the water quality slowly improves, Richardson said, she hopes the Anacostia’s reputation is also rehabilitated. Even if it’s not safe to swim in, Richardson enjoys boating trips like the one with the Anacostia Riverkeeper.
“To see all those creatures along the way and the greenery. It was comforting,” she said. “So rather than take a pill to settle my nerves, I can just go down the river.”