Hundreds of NYC cooling towers issued Legionella testing violations since last year – as plumbers union calls for new regulations

Hundreds of cooling towers around the Big Apple were dinged by health inspectors over issues relating to Legionella testing since last year, The Post has learned.

Nearly 250 water cooling towers – more than half of which are in Manhattan – were issued violations after the health department found Legionella samples were “not collected, analyzed or results [were] not reported” to the health department, as mandated by law, since Jan. 1, 2025.

Another 44 cooling towers in Brooklyn were cited for the same non-compliance issue, as well as 22 in the Bronx; 19 in Queens and one in Staten Island. 

The news comes after an Upper East Side cluster has sickened more than 63 and hospitalized 52 this month. 

More than half of cooling towers in the affected outbreak area — spanning Yorkville and Carnegie Hill — were dinged for violations in the past year, a Post analysis revealed. 

“As part of our Legionnaires’ investigation on the Upper East Side, the health department found 73% of the cooling towers in the investigation area have provided the required information,” health department spokesperson William Fowler said, adding the citywide compliance rate hovers at 77%.

“All cooling towers that test positive for the presence of Legionella are now undergoing a full inspection,” he said. “Some of the cooling towers that did not upload information may not be in operation, or have yet started up.”

The latest non-compliance data includes 17 Legionella testing-related violations at cooling towers in Midtown East and 14 in downtown Brooklyn and Hell’s Kitchen.

Four repeat-offenders – in Midtown East, Greenpoint, Washington Heights and Chelsea – were also dinged more than twice over the past year.

A new law that went into effect in May requires cooling towers to report testing every month instead of every 90 days, and fines start at $500 — and can rise to $2,000 for repeat violations.

But union members of Plumbers Local 1 say even those regulations, which aren’t often followed, aren’t enough to keep New Yorkers safe, and are now urging the health department to mandate more comprehensive testing.

“Waiting for people to get sick before testing is a failed, reactive strategy,” the group, representing 6,000 members across the city, told The Post.

The union is now calling on the city to mandate comprehensive building water testing, including in domestic water lines, for facilities over a certain size every three to six months. 

“The cooling towers are where it’s ending but it’s not necessarily where it’s beginning,” said Paul O’Connor, business manager of UA Plumbers Local 1. “So those cooling towers are fed off of domestic water lines, as well as roof tanks.

“We need to stop the crisis before it starts,” he said of the beefed-up requirement — which would employ plumbers to do the inspections.

The Upper East Side cluster did not stem from a building water system, but a cooling tower — although building water system-related Legionnares’ disease cases still sicken roughly 100 New Yorkers annually.