Local Law 77 — Cooling Tower Registration, Inspection, and Legionella Testing

Who is covered

Any building or facility in New York City that operates one or more cooling towers, evaporative condensers, or fluid coolers.

What the law requires

• Register each cooling tower with DOHMH within 30 days of installation or operation.
• Develop and maintain a Maintenance Program & Plan following ASHRAE Standard 188 or equivalent.
• Collect Legionella culture samples at least every 31 days while the tower is in operation (LL159/2025) and upload each sample date to the DOHMH portal within 5 days.
• Have a qualified person perform a compliance inspection at least every 90 days during operation.
• Submit an annual certification to DOHMH confirming compliance with all maintenance and testing requirements.
• Immediately report any Legionella test result exceeding the action level to DOHMH and initiate disinfection.

Filing frequency and deadlines

Penalty structure

Non-compliance with LL77 can result in the following penalties:

• $2,000 to $5,000 for failure to submit the annual certification.
• $1,000 to $2,000 per tower for failure to register.
• $1,000 to $2,000 per missed Legionella sampling event.
• Emergency shutdown orders for towers with positive Legionella results that are not properly addressed.

Exemptions

• There are no exemptions — all cooling towers must comply regardless of building type or size.

Recent updates and amendments

Local Law 159 of 2025 (effective May 8, 2026) changed Legionella culture sampling from every 90 days to at least every 31 days while the tower is in operation, with sample dates uploaded to the DOHMH portal within 5 days. Verify the exact effective date and any phase-in against the DOHMH rule before relying on it for an enforcement-sensitive date.

Reference

Official source: NYC DOHMH — Cooling Towers