Legionella Found in 17% of NYC Water Samples Outside Cooling Towers
Washington – September 08, 2026 -- Independent testing commissioned by the Alliance to Prevent Legionnaires' Disease (APLD) found Legionella bacteria in 17 percent of 109 water samples collected from sinks, showers, hose bibs and other fixtures across the Upper East Side outbreak zone, results the group says expose gaps in New York City's current prevention strategy.
Testing detected live, culturable Legionella pneumophila serogroup 1 across all three sampled zip codes
The independent consultant collected samples in mid-July across zip codes 10128, 10028 and 10075, the area the City identified as the outbreak zone. Legionella was found in 19 buildings, including 10 exterior hose bibs, seven sinks, one shower and a decorative fountain. Positive samples showed Legionella concentrations ranging from less than 1 to 390 CFU/mL, with Legionella pneumophila serogroup 1 confirmed in all three zip codes.