Legionella is a waterborne bacterium that lives naturally in freshwater but becomes dangerous when it colonizes building water systems. When contaminated water is aerosolized through showers, faucets, cooling towers, decorative fountains, or hot tubs, people can inhale the droplets and develop Legionnaires’ disease, a severe and sometimes fatal form of pneumonia. In the Augusta area and across Georgia and South Carolina, the combination of warm climate, high humidity, and aging building infrastructure makes Legionella a real operational concern for commercial and institutional property owners.
The question most building owners ask is whether their water system is actually at risk. The honest answer is that without testing, there is no way to know. Legionella grows in water systems that appear clean, passes standard visual inspections, and does not produce any odor or discoloration that would alert building staff. Routine water sampling is the only reliable way to detect a problem before someone gets sick.
Which Buildings Face the Highest Risk
Any building with a complex water distribution system can harbor Legionella, but certain characteristics increase the likelihood of growth. According to the CDC, Legionella thrives in warm, stagnant water and in systems with scale, rust, or biofilm. Buildings most commonly associated with Legionella risk include:
- Hotels and resorts with large plumbing systems, cooling towers, and high guest turnover
- Hospitals, nursing homes, and assisted living facilities, where immunocompromised residents are at the highest risk of severe disease
- Large office buildings and commercial properties with complex hot and cold water distribution
- Multifamily residential buildings with centralized hot water systems
- Fitness facilities with showers, pools, hot tubs, and misting equipment
- Schools, universities, and government buildings, especially those with seasonal shutdowns that allow water to stagnate
Any building that has undergone recent renovation, experienced periods of low occupancy, or had changes to its plumbing configuration should be treated as elevated risk. Construction and renovation create dead legs in plumbing systems where water sits stagnant. Low occupancy during holidays or off-peak seasons reduces water turnover, allowing temperatures to drift into the range where Legionella multiplies most rapidly.
Regulatory Requirements: ASHRAE 188 and CMS
There is no single federal law that requires all buildings to test for Legionella, but regulatory pressure on high-risk facility types is increasing. Two standards are the most relevant for building owners and operators in Georgia and South Carolina.
ASHRAE Standard 188, “Legionellosis: Risk Management for Building Water Systems,” establishes the industry framework for water management programs in commercial buildings. It requires covered facilities to develop and implement a written water management program that identifies hazardous conditions, establishes control measures, and includes monitoring and verification steps. ASHRAE 188 applies broadly to buildings that meet certain size and system thresholds, and compliance with it is increasingly referenced in insurance requirements and liability assessments.
The Centers for Medicare and Medicaid Services (CMS) issued a memorandum in 2017 requiring all Medicare and Medicaid-certified facilities, including hospitals, nursing homes, and dialysis centers, to have water management programs that address Legionella risk. CDC guidance on Legionella testing for buildings without known cases supports routine environmental sampling as a tool to verify that water management programs are working as intended. For healthcare facilities, this is not optional — it is a condition of participation in federal healthcare programs.
Conditions That Increase Risk in Your System
Even well-maintained water systems can develop conditions that allow Legionella to multiply. The most common contributing factors are:
- Water temperature between 77 and 113 degrees Fahrenheit, the range where Legionella grows most rapidly
- Stagnant or low-flow areas such as dead-end pipe runs, infrequently used outlets, or sections of the system that were isolated during renovation
- Biofilm buildup inside pipes, tanks, and fixtures, which provides nutrients and protection for Legionella colonies
- Scale and sediment in water heaters and storage tanks that reduce the effectiveness of thermal disinfection
- Inadequate or inconsistent disinfectant levels throughout the distribution system
These conditions often develop gradually and without visible warning signs. A water heater thermostat set slightly low, a wing of a building that went unused for two months, or a cooling tower that was not properly cleaned before startup can all create the conditions for Legionella growth without triggering any alarm.
What Legionella Testing Involves
Environmental Legionella testing involves collecting water samples from specific points in the building’s water system — showers, faucets, cooling tower basins, hot water storage tanks, and other high-risk outlets — and sending them to an accredited laboratory for culture or PCR analysis. Sampling plans should be designed to cover the areas of highest risk in your specific building configuration, not just a random selection of outlets.
Results tell you whether Legionella is present, at what concentration, and in which parts of the system. A positive result triggers remediation steps such as hyperchlorination, thermal disinfection, or system flushing, followed by confirmatory testing to verify that the treatment was effective. A negative result, documented properly, is part of the compliance record that demonstrates your water management program is functioning as intended.
Schedule a Legionella Assessment for Your Facility
EnviroPro 360 provides Legionella water sampling and testing for commercial, healthcare, hospitality, and multifamily properties throughout Augusta, North Augusta, Aiken, and the surrounding CSRA. We develop targeted sampling plans for your specific building, coordinate sample collection with your operations team, use accredited laboratory analysis, and deliver clear reporting that supports your water management documentation requirements.
If you manage a building where Legionella risk is a compliance concern or where you simply want to know what is happening in your water system, testing is the right first step. Contact EnviroPro 360 to schedule a Legionella risk assessment and sampling plan for your facility.
