When an outbreak of Legionnaires’ Disease in the South Bronx killed at least 12 people and sickened hundreds more in the summer of 2015, the city and state rushed to enact sweeping regulations in an effort to prevent a similar episode in the future.

Listen to WNYC's Sean Carlson and Lylla Younes discuss what they found in their analysis:

The regulations specifically target cooling towers; the big, boxy machines on city rooftops that regulate air conditioning systems in large buildings. Cooling towers are often confused with the iconic cylindrical structures on city rooftops that store drinking water. (Water towers have their own issues.) Cooling towers collect and vaporize warm water that can contain legionella bacteria. People contract the disease by breathing the contaminated vapor when it floats down to the street level.

To combat the disease, owners of cooling towers are required to have their machines inspected every 90 days, and cleaned immediately if the amount of legionella bacteria present is above a certain level. But an analysis of the state’s cooling tower inspection records reveals that greater than 1,190 towers around New York City, more than 20 percent, are behind on their quarterly inspections.

Data: NYS Department of Health Cooling Tower Inspection Data, updated weekly. (Lylla Younes, Gothamist/WNYC)

Over 80 percent of non-compliant cooling towers were in Manhattan, with less than a hundred in Brooklyn, Queens and the Bronx. Approximately 24 percent of noncompliant towers were last inspected in August of 2015, shortly after the regulations were issued. Most non-compliant cooling towers did not contain a hazardous amount of legionella at the time of their last inspection, but the 18 units that did have not been checked in over a year.

Diagnosed cases of Legionnaires’ in New York City are rising. The Alliance to Prevent Legionnaires Disease, a nonprofit dedicated to combating the disease around the world, points to federal data that showed a 64 percent spike in cases around the city last year compared to 2016. It’s unclear how many of these cases were caused by cooling towers.

Listen to Sean Carlson's report for WNYC:

Jeffrey Hammond, a spokesperson for the New York State Department of Health, said the focus since 2015 has been educating cooling tower owners, and that the agency will now shift to enforcement. Hammond also said the state keeps separate data on cooling towers than the city.

But the city, unlike the state, does not publish inspection data for cooling towers. Gothamist asked the NYC Department of Health and Mental Hygiene for that data. After a month, the city said the information is only available through a freedom of information request.

The city law mandates that the Health Department file annual reports tracking data on inspections, but when asked they only produced reports showing information through November 2016. The most recent report shows that almost half of the cooling towers registered to the city have not filed required information on inspections.

The report also shows that the city Health Department inspected nearly 1,000 towers on its own that year, and issued nearly 1,000 violations. These violations, while not necessarily all related to the presence of Legionella, are still disturbing. More than 65 percent were considered “critical.” Nearly 20 percent were considered a public health hazard.

The new city law, Local Law 77, mandates that the Health Department file a report by May 15 of this year with the latest data. When asked for that report, a spokesman for the health department said it was in the process of being finalized.

An air cooling unit on the roof of Lincoln Hospital in the Bronx, August 4, 2015 (Seth Wenig/AP/REX/Shutterstock)

City Councilman Ben Kallos was a co-sponsor of the law. He says if the data is correct and there really is widespread noncompliance with the state and city rules, the city should do something about it.

“We need to know if the legislation we passed is actually working,” Kallos said.

Meanwhile, some advocates say the law isn’t working. Brad Considine is the director of strategic planning at the APLD. He believes that New York City residents are not getting their money's worth for the law, which costs cooling tower owners approximately 130 million dollars a year.

“The whole thing is misguided, but they did it over a weekend,” Considine said, referring to the city’s legislation. “They felt political pressure and their political interests and business interests [are] driving this discussion, and meanwhile people are getting sick and dying.”

This story was co-reported by WNYC and Gothamist.

Data for the analysis is maintained by the state in a public database of every cooling tower registered since 2015. The state Health Department said the data is updated weekly. The city and state determine that a cooling tower has a hazardous amount of legionella bacteria if the tower’s liquid contains greater than 1,000 Colony Forming Units (CFU) of legionella per ml.

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