In a recent article published by Water Conditioning & Purification International Magazine, Christopher Lloyd, PhD., founding partner of RETEGO Labs, LLC, and VP of Technology, confirms the presence of alarmingly high levels of bacteria within the premise piping of various buildings with low or no use during the recent pandemic.
“Recent testing conducted by our company confirms that buildings subjected to shutdowns or reduced utilization have shown a deterioration in their water quality when returning to pre-pandemic schedules,” explains Lloyd. “This decline in quality has been traced to stagnant water within the buildings.”
Lloyd added that numerous buildings have shown dangerously high bacterial contamination levels (>1,000,000 cfu/mL of slime molds and iron-related bacteria) within the premise piping.
In anticipation of re-opening the economy, the US EPA and the CDC issued the following guidelines for all properties affected by the shutdown:
“Building and business closures for weeks or months reduce water usage, potentially leading to stagnant water inside building plumbing. This water can become unsafe to drink or otherwise use for domestic or commercial purposes. For example, optimal growth conditions for undesirable pathogens, such as Legionella bacteria, can occur when hot water temperatures decrease and disinfectant residuals (e.g., chlorine) drop to low levels.
Water chemistry changes may also increase corrosion and leaching of metals, including lead, and may cause the formation of disinfection by-products. Turning on the water for immediate use after it has been stagnant can pose a risk to public health if not properly managed. Additionally, turning on water after a prolonged period of non-use could disrupt pipe and plumbing scales to such an extent that microbial and chemical contaminants could be released into the water.”
In January, the CDC issued its Legionella Toolkit that is “designed to help people understand which buildings and devices need a Legionella water management program to reduce the risk for Legionnaires’ disease, the key elements of a water management program, and how to develop it.” This Toolkit can be found online at www.cdc.gov/legionella/wmp/control-toolkit/index
Lloyd mentioned that a key component to the CDC Toolkit is the reference to the ASHRAE 12-2020 guideline, which is designed to help in reducing the risk of dangerous levels of bacterial growth in buildings:
“18.104.22.168 Growth. Biofilms play an important role in Legionella growth. Biofilms are complex and dynamic microbial ecosystems that form on surfaces within the building water systems. Biofilms impair the effectiveness of physical and chemical control methods, such as maintaining hot-water temperatures and applying chemical disinfectants. Legionella bacteria are known to invade and replicate within protozoa that are associated with biofilms. While inside these protozoa, the Legionella bacteria are further shielded from disinfectants and temperature extremes. Key factors that contribute to Legionella growth include sediment, temperature, water age, and disinfectant residual.”
Lloyd concluded that the majority of problems associated with OPPPs (and with the biofilms that allow their propagation and survival), can be addressed with a water management plan that uses the detection of residual chlorine to ensure the health and safety of premise plumbing.
To read the complete WCP International Magazine article, click here.