Cleaning & Legionnaires

Cooling Tower Cleaning & Legionnaires' Disease

Why Regular Maintenance Is Critical for Health, Compliance, and Efficiency

Cooling towers are essential components of many commercial and industrial HVAC systems. However, if not properly maintained, they can become serious public health hazards. One of the most dangerous risks is the proliferation of Legionella bacteria, which causes Legionnaires’ disease—a potentially fatal form of pneumonia transmitted through inhaled water droplets.

As trusted specialists in cooling tower cleaning and disinfection in Northern California, WaterSystems Cleaning is committed to helping facility managers reduce risk through technical expertise and regulatory compliance.

Understanding Legionnaires' Disease

Legionnaires’ disease is a severe respiratory infection caused by Legionella pneumophila, a bacterium that thrives in warm, stagnant water. Outbreaks are frequently linked to large, complex water systems such as:

People can contract the disease by inhaling aerosolized water droplets that contain Legionella. According to the Centers for Disease Control and Prevention (CDC), roughly 1 in 10 infected individuals will die from the illness. (CDC)

Why Cooling Towers Pose a High Risk

Cooling towers provide an ideal environment for bacterial growth, especially when maintenance is neglected. Risk factors include:

Without regular inspection, cleaning, and water treatment, these systems can become breeding grounds for Legionella, increasing the risk of aerosolized bacteria spreading throughout a facility or its surrounding area.

Regulatory Compliance & Industry Best Practices

Multiple agencies and standards address Legionella control in cooling towers:

ASHRAE Standard 188

Mandates development of a site-specific water management plan that identifies and mitigates risk factors. (ASHRAE 188)

OSHA Guidelines

Recommends cleaning and disinfecting cooling towers at least twice per year as part of a broader water safety program. (OSHA)

California Building Standards Code (Title 24)

Requires proper design, maintenance, and operation of mechanical systems that include cooling towers.

Local Health Regulations

Counties like Santa Clara and Alameda have implemented stricter oversight and proactive inspections due to past outbreaks.

Key Practices for Legionella Prevention

A comprehensive, proactive cooling tower maintenance plan should include:

Quarterly Cleaning & Disinfection

Especially important for high-risk settings such as hospitals, data centers, and industrial campuses.

Biocide Dosing & Water Chemistry Monitoring

Ensures bacterial control and prevents scale buildup.

Legionella Testing

Recommended after prolonged inactivity, construction events, or system reactivation.

Mechanical Inspections

Identifies debris accumulation, pump failure, or poor drift eliminator performance.

At WaterSystems Cleaning, we customize each plan based on usage intensity, environmental exposure, and cooling load.

The Cost of Neglect: Health, Legal & Operational Risks

Failing to maintain your cooling tower doesn’t just risk non-compliance—it can have serious consequences:

Health outbreaks and public exposure
Financial penalties and liability lawsuits
System shutdowns by local health authorities
Loss of energy efficiency and increased utility costs
Reputational damage in regulated industries

Final Thoughts

In an innovation-driven region like Northern California, facility safety and reliability are non-negotiable. Preventing Legionnaires’ disease starts with regular cooling tower cleaning, water quality control, and documentation aligned with ASHRAE and OSHA standards.

Don’t wait for a problem to appear. Contact WaterSystems Cleaning to develop a proactive, compliant maintenance strategy today.