New Measures Aim to Bolster New York City’s Legionella Response
New measures announced last week by the New York City Health Department and Mayor Zohran Mamdani are intended to improve the city’s efforts to address Legionella bacteria in cooling towers. The initiatives follow an outbreak of Legionnaires’ disease that affected the city’s Upper East Side this summer, resulting in 94 cases and 11 deaths. The new measures will focus on accelerating remediation of cooling towers in affected areas, identifying potentially unregistered cooling towers, and enhancing transparency, among other efforts, according to a news release from the Office of the Mayor.
The density of cooling towers in the Upper East Side presented a challenge for investigators, who had to sample almost four times as many towers as they did during last year’s community cluster of Legionnaires’ disease in Central Harlem. Cooling tower remediation results posted on the NYC Health website state that 183 cooling towers at 160 buildings were tested for Legionella during the Upper East Side investigation. Seventy-seven cooling towers at 75 buildings tested positive for Legionella during initial PCR screening tests, and 59 towers and 58 buildings later tested positive during culture testing intended to identify which cooling towers contained live bacteria. As cultures can take up to two weeks to produce results, one of the new measures announced by the city’s health department aims to “reduce the time it takes to test and confirm positive results” by “[exploring] faster culture methods and novel testing approaches.” The health department intends to implement this measure in the coming years, as additional staff and resources will be required.
Another new measure will formalize a partnership between New York City’s health department and its Department of Buildings to address cooling tower registration issues. According to the news release from the mayor’s office, the health department identified unregistered cooling towers during its investigations of Legionnaires’ disease in both the Upper East Side and Central Harlem. The city intended to connect the Cooling Tower Registration Portal, administered by the health department, and the Department of Buildings’ construction permitting system, which “will help ensure more cooling towers are registered in the first place before they are ever turned on.”
The health department also plans to launch a new mapping feature for its cooling tower lookup tool that will show users the locations of registered cooling towers across the city and provide information about towers’ inspection history and compliance with Legionella sampling requirements. A public education and media campaign is set to launch alongside the new mapping tool by spring 2027.
Additional measures announced last week involve improving enforcement of cooling tower violations and convening a scientific advisory panel to evaluate emerging technologies and explore systems that could help reduce the city’s reliance on cooling towers.
Further details can be found in the Office of the Mayor’s news release.
Related: Read “Legionella Regulations in New York: How Much Progress Have We Made?” and “Why Legionnaires’ Disease Outbreaks Continue” in the digital Synergist.