Preventing legionnaires' disease

Preventing legionnaires' disease

Mandatory notification of cooling towers and warm-water systems

To control legionnaires' disease we maintain a register of water-cooling systems in premises (including cooling towers and warm-water systems) in hospitals and nursing homes. Owners and occupiers who install and operate such systems must notify the City under the Public Health Act 2010.

City environmental health officers inspect water-cooling systems to ensure maintenance complies with the Public Health Act 2010 and the Public Health Regulation 2012.

To register a water-cooling or warm-water system or update information on the register, please download the notification form and email a scanned copy to

Regulatory changes to the management of water-cooling systems

An amendment to the Public Health Regulation 2012 was published on 1 December 2017 and the new requirements started on 1 January 2018.

The new approach introduces a more stringent requirement for registered occupiers of buildings to manage their water cooling systems to control the risks associated with Legionella bacteria. 

This approach is in line with Australian Standard 3666 (Air-handling and water systems of buildings – Microbial control) and other jurisdictions in Australia and internationally.

Under this amendment, the occupier of premises that contain a water-cooling system must ensure that: 

  • all water-cooling systems are tested monthly for Legionella count and heterotrophic colony count
  • reportable test results of Legionella count >1000 cfu/mL and heterotrophic colony count >5,000,000 cfu/mL must be notified to the local council within 24 hours by the occupier where the cooling tower is installed. 

The first monthly test must be completed before 1 February 2018.

To report a high Legionella count or high heterotrophic colony count, contact the City on 02 9265 9333 or

Please note, further changes to the regulation are proposed. When changes have been published, we will update this information. Please refer back to this webpage for details. 

For further information on the NSW Health requirements, please visit NSW Health: Legionella control.


The City’s authorised officers can order a system to be maintained or shut down if an inspection and/or sampling finds evidence of/or risk of conditions that support the growth of Legionella

If you no longer use a cooling tower, it must be drained and you should notify the City. 

Failure to comply with these requirements can result in legal notices and orders being issued and/or prosecution. 

What is legionnaires’ disease?

Legionnaires' disease is a potentially fatal type of pneumonia caused by Legionella, a bacteria that may also cause a flu-like condition called Pontiac fever. These conditions can affect everyone but vulnerable groups can be more susceptible. These include older people with existing health problems such as respiratory disease or if they're taking immune-suppressant drugs, heavy smokers and heavy drinkers.

Legionnaires' disease occurs when someone inhales the organism that penetrates deep into the lungs, possibly through a contaminated aerosol from a cooling tower.

Legionella can be controlled by proper water treatment procedures and regular cleaning.


We hold free workshops for anyone who operates a water-cooling system in the local area. This is a simple way to get cooling tower safety messages across to owners, occupiers and building managers.

The course is an excellent resource on controlling Legionella in cooling towers and how to maintain cooling tower systems. It also covers complying with the Public Health Regulation requirements and preventing the spread of Legionella.

Making sure that building managers have the right skills and knowledge will help you to meet your legal obligations. Better knowledge and practices will:

  • prevent an outbreak of Legionella
  • improve record keeping
  • help you to avoid heavy fines or even imprisonment.

Upcoming event dates will appear on this site, or you can contact the City at the number below.


Standards and Policy, Health and Building

02 9265 9333 

Last updated: Monday, 16 July 2018