Legionella Risk Management & Water Systems




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Legionella bacteria can grow rapidly in building water systems, particularly when temperature and other conditions are favourable. Although this can include warm water systems, spa pools and even decorative fountains, outbreaks are often attributed to cooling towers, which can potentially disperse contaminated aerosols to a wide area.

Greencap consultants have been assisting clients with Legionella and water system risk management for over three decades. Currently, teams manage microbiological testing and corrosion monitoring programs on behalf of a diverse range of clients across Australia and New Zealand in a wide variety of industries including:

  • Industrials and manufacturing
  • Healthcare and hospitals
  • Retail
  • Commercial premises


The operation of cooling towers is regulated by state-based legislation throughout Australia. These prescribe various requirements around registration (some states not all), cleaning/inspection/maintenance requirements and regular water testing requirements. There is also a requirement for Risk Management Plans (and annual independent auditing) in Victoria and more recently NSW. 

The Greencap team has a depth of expertise around plant and equipment, including a variety of heating, ventilation and air conditioning (HVAC) systems – particularly in the area of Legionella risk and water system risk management. Consultants are experienced in  the writing, reviewing and auditing of cooling tower Risk Management Plans and Risk Assessments.


Greencap Services


  • Development of tailored Risk Assessments and Risk Management Plans (RMP) for:
    • Cooling Water Systems
    • Cold and Heated Water Systems
    • Water Features
    • Car Wash Stations
    • Other water systems
  • Cooling Water System Independent Audits;
  • Risk assessments to ensure compliance in water delivery systems;
  • Microbiological testing and corrosion monitoring program management;
  • Root cause analysis following adverse results or system failure.


What Is Legionnaires’ Disease?

Legionnaires’ disease is generally considered to be acquired through the inhalation of aerosols contaminated with Legionella bacteria.  Symptoms can include fatigue, muscle pains, headache, fever, non-productive cough, shortness of breath, nausea, abdominal pain, vomiting and diarrhoea.  Legionellosis (which includes Pontiac fever) has a low attack rate and is more likely to affect individuals with an underlying illness or a weakened immune system, including people with lung diseases, the elderly and smokers. 


Legislation to Manage Warm Water Delivery Systems

Many people mistakenly assume that legionella is only a risk in cooling towers – there are potential risks in warm water systems as well which need to be appropriately managed. Like Cooling Towers, Warm Water Systems do have state-based legislative requirements to manage the risk of Legionella infection. Prescription is provided around testing and management requirements in various premises seen to be of ‘increased’ risk such as aged care and health/hospital services. 


Read the Greencap Risk Review here: Monitoring & management of water in buildings 

Greencap acknowledges the Traditional Owners of Country throughout Australia and recognises their continuing connection to land, waters and culture.  We pay our respects to their Elders past, present and emerging.