Regulated Water Systems

Water Cooling Systems – Cooling Towers, and Warm Water Systems

Regulated Water Systems must be managed safely in order to prevent the growth and transmission of Legionella bacteria. Infection may cause Legionnaires’ disease, a serious and potentially life-threatening condition. The Public Health Act 2010 and Public Health Regulation 2022 define the roles and responsibilities for managing cooling water systems and other regulated systems.

Building occupiers are required to ensure that there are six key safeguards in place for their cooling water systems:

  1. A competent person must undertake a risk assessment of Legionella contamination, documented in a Risk Management Plan (RMP) – every five years (or more frequently if required)
  2. Independent auditing of compliance with the RMP and Regulation – every year
  3. Providing certificates of RMP completion and audit completion to the local government authority
  4. Sampling and testing for Legionella and heterotrophic colony count – every month
  5. Notifying reportable laboratory test results (Legionella count ≥1000 cfu/mL or heterotrophic colony count ≥5,000,000 cfu/mL) to the Willoughby City Council  within 24 hours after they are received by the occupier
  6. Displaying unique identification numbers on all cooling towers.

All Cooling water and warm-water systems must be registered with Council. Council also should be notified of any changes to the owner, the occupier, emergency contact and the regulated system through the registration form.

Notification of reportable test results

The Public Health Regulation 2022 (the Regulation) requires occupiers to ensure that the cooling water system is tested for Legionella count and heterotrophic colony count (HCC), on a monthly basis. Occupiers must notify the Local Government Authority (LGA) within 24 hours of receiving a reportable test result of Legionella count ≥1,000 colony forming units per millilitre (cfu/mL) or HCC ≥5,000,000 cfu/mL.

Approved Form 4 must be completed in accordance with section 18 of the Regulation. Further information on the process of notification and responding to elevated microbial levels is provided in the NSW Guidelines for Legionella Control in Cooling Water Systems (the Guidelines).

The form shall be submitted to Council AND to Team Leader Safe City Unit mark.hayward@willoughby.nsw.gov.au.

Register now

Warm-water systems for hospitals and high-level care residential aged care facilities must also be registered with Council. Thermostatic Mixing Valves (TMVs) are the most common example of a warm-water system. Details of all TMVs at each property address can be registered on one form as one system if accompanied with a list detailing each TMV system.

There are statutory penalties for those who fail to comply with legislation. The responsible person is guilty of an offence if their tower is not registered with Council or has not been maintained as required.

For further information and relevant legislative documents visit  NSW Health.

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