This article is a collaboration with THE CITY.Water testing at a major federal building in Lower Manhattan that houses immigration court and federal law enforcement offices has found bacteria that can cause Legionnaires’ disease in dozens of locations, THE CITY and Healthbeat have learned.The U.S. General Services Administration, which operates the building, found Legionella in the water at 81 locations at 26 Federal Plaza, according to documents obtained by THE CITY. Legionella is a bacteria that can cause the disease, a severe form of pneumonia.The water quality tests were conducted between August 23 and 25, according to an email sent Sunday night from building staff to members of the Department of Justice, which has offices in the building. The results found Legionella in water sources all over the building, including in kitchens, locker room showers, drinking fountains and daycare sinks. The test also found elevated levels of copper in two separate rooms and elevated levels of lead in a lactation room faucet.Signs announcing the results of the water tests greeted people as they entered the building at the visitors’ and employee entrances on Monday: “Legionella has been detected in the drinking water system — normal use may continue.”An employee who works on the eighth floor found out about the presence of Legionella only after a building cleaner showed him a picture of one of the posted notices on Monday afternoon.“One of our contractors came up to me and said, ‘Do you know anything about this?’” he recalled. The employee, who requested anonymity because his job doesn’t allow him to speak to the media, hadn’t received any communication from the building staff about the issue.He then asked another coworker, but they hadn’t heard anything either. “I am very unhappy that we didn’t get an email about this,” he told THE CITY. “I’m drinking water that I brought!”More than a dozen employees who spoke with a reporter outside the building on Monday were unaware of the Legionella, and hadn’t noticed the signs the building had posted.Water in the building at 26 Federal Plaza in New York City was found to have bacteria that can cause Legionnaires’ disease. (Ben Fractenberg / THE CITY)The 41-story complex at 26 Federal Plaza is home to a number of prominent federal agencies, like the Department of Homeland Security, the New York branch of the Federal Bureau of Investigation, and the U.S. Court of International Trade and Immigration Court.Dr. Waleed Javaid, a professor of medicine at the Icahn School of Medicine at Mount Sinai and a director of infection prevention and control, stressed that the presence of Legionella alone should not be too alarming, unless people begin getting sick.For workers in and visitors to a building where Legionella has been detected, the risk of developing Legionnaires’ disease is likely low, he said. Still, he encouraged people to follow posted guidance and reach out to their health care providers if they are concerned or develop symptoms.“If they’ve been exposed, the exposure itself wouldn’t really cause them to get Legionnaires’ unless the Legionella bacteria gets into their lungs, or if they have some preexisting condition that causes them to get the illness,” he said. “If they develop pneumonia, a respiratory illness, that’s when I’d start getting concerned.”A GSA spokesperson said in a statement there are “no known active public health case investigations” of Legionnaires’ disease linked to the water supply at 26 Federal Plaza. This year, as part of a “proactive water quality management program,” the agency is testing the drinking water at thousands of the facilities it oversees.The agency has begun the “flushing of all point-of-use outlets and hot water tanks, equipment evaluation to ensure proper functionality and cleaning or replacement where necessary, and reviewing operations, such as temperature set points and chemical characteristics of incoming water to the building.”Pattern of contaminationThis is not the first time in recent years that the federal agency overseeing the government’s workplaces has found Legionella bacteria in its buildings.A memo released last September by the GSA’s Office of Inspector General reported that since that July, elevated levels of the bacteria had been detected in the water at six GSA-controlled buildings across the country, including in New York, Nebraska, Illinois, Utah and Michigan.In New York, elevated levels of Legionella were detected at the Lewiston Bridge Land Port of Entry, at the U.S-Canada border.In the memo, an assistant inspector general urged the Public Buildings Service, a division of GSA that oversees workplaces for civilian federal agencies, to take “immediate action to address the risk of Legionella contamination in water systems” across buildings owned and leased by GSA.The problem dates back even further, according to the inspector general. In September 2022, that office had alerted the Public Buildings Service that it did “not effectively test for water contamination, including Legionella” in GSA-operated child-care centers. The memo noted that the elevated Legionella levels detected in 2023 coincided with reduced building occupancy, which can lead to water stagnation — a favorable condition for bacterial growth.At 26 Federal Plaza, Legionella was found in five distinct locations in a room that served as a daycare center. It was also found in a sink on an early childhood learning floor, and in five places in four different classrooms.The inspector general memo noted that the Public Buildings Service’s approach to Legionella testing was “not comprehensive or consistent” and urged the division to improve its testing requirements and tighten its oversight of its properties. In January, a GSA official highlighted expanded water testing efforts in its buildings.The agency manages a massive portfolio of real estate. GSA owns 1,600 federal buildings and leases space in more than 6,500 buildings across the country, according to the memo.Deadly risk for someMost healthy people exposed to Legionella bacteria do not get sick, according to the Centers for Disease Control and Prevention. Current or former smokers, people 50 years or older, and people with cancer, chronic lung disease, diabetes, kidney failure, liver failure and a weakened immune system are at increased risk of developing Legionnaires’ disease.Symptoms can include a cough, fever, headaches, muscle aches and shortness of breath. The disease can be successfully treated with antibiotics, though it can require hospitalization. About one in 10 people with Legionnaires’ disease die due to complications, according to the CDC.The likelihood of becoming sick from Legionella is higher in places where people stay for longer periods of time, including apartment buildings and hospitals, Dr. Javaid said.“If you’re just going there or you’re working there, the risk is exceedingly low, but not zero,” he said. “There is always a risk that you can acquire bacteria like this from working in a place that may have Legionella there.”The bacteria occurs naturally in lakes and streams, and doesn’t typically pose a risk unless it enters a building’s water system and multiplies there, where stagnant water and warm temperatures can lead to bacterial growth.People can become sick by inhaling water droplets containing the bacteria, including from showerheads, hot tubs, and centralized air-cooling systems. Legionella isn’t typically a concern in drinking water, although in rare cases, someone can become infected if they accidentally swallow water containing the bacteria that ends up in their lungs, according to the CDC.From 2019 to 2023, there were more than 4,000 cases of illness caused by Legionella, including Legionnaires’ disease and a milder condition called Pontiac fever, in New York state, according to the state Department of Health. In 2021, New York reported more cases of those illnesses than any other state.Clusters of Legionnaires’ disease have also emerged in New York City Housing Authority developments in recent years. In February, THE CITY reported the death of a NYCHA resident from the disease.The number of Legionnaires’ disease cases has fluctuated in New York City from 2010 to 2022, with a peak of more than 600 cases in 2018, according to a city health department report.The bacteria can be particularly dangerous in health-care facilities. Last week, officials announced the deaths of three people who tested positive for Legionnaires’ disease amid an outbreak of cases at an assisted living home in Albany. In 2022, five people died from the disease at a Manhattan nursing home.The building at 26 Federal Plaza has rooms designated for “healthcare,” “health unit” and “health center,” according to the documents obtained by THE CITY and Healthbeat. Legionella was found in six of them.Eliza Fawcett is a reporter covering public health in New York City for Healthbeat. Contact Eliza at efawcett@healthbeat.org. Rachel Kahn is an intern at THE CITY, a non-profit newsroom that serves the people of New York through independent journalism.