Legionella is a bacterium that causes Legionnaires’ disease, which is a severe form of pneumonia. Most people catch Legionnaires’ disease by inhaling water droplets carrying the bacteria from the mist produced by conditioning units and showerheads or sink faucets. People most susceptible to the bacterium are elderly and immunocompromised persons. NOVA creates facility water management plans and regularly conducts legionella water sampling in accordance with the CDC Elite Procedures. In addition, we provide recommendations on how to properly manage building water systems in order to manage and/or prevent the growth and spread of legionella in building water systems.