The Next Bacterial Concern: Legionella and Premise Plumbing

Life in 2020 has been upended by a series of turbulent events – most notably the COVID-19 pandemic and widespread social protests spreading across America – leading to widespread lockdowns and temporary abandonments of office and public infrastructure. As states across the country begin to slowly reopen amidst these once-in-a-generation circumstances, their populations may unknowingly be walking into yet another disruptive, bacterial concern within their offices, restaurants, and buildings.

Empty buildings and unattended HVAC systems, while seemingly nondescript, oftentimes unintentionally promote the unwanted consequence of harmful bacteria growth in stagnant plumbing systems running overhead. Legionella pneumophila, commonly known as legionella, is a bacterium that, when aerosolized, can be inhaled by humans and cause outbreaks of Legionnaire’s Disease within populations with weakened or compromised immune systems such as hospitals and nursing homes1. Warm stagnant water, rust, scale, and the presence of other microorganisms all correlate strongly with the rise of legionella populations, and also happen to be predominant characteristics of unattended premise plumbing fixtures and cooling towers. Legionnaire’s disease causes severe pneumonia, fever, muscle aches, and shortness of breath in individuals and populations with compromised immune systems. The disease infects 52,000 people annually in the US, resulting in the death of one in ten of those afflicted4, rendering it nearly one hundred times as deadly as typical influenza5. How has this bacterial infection, yet another unseen threat in our lives, managed to escape attention for so long?

As the US broadly begins to phase in state reopenings, the water industry, unsurprisingly, will once again play a role in making sure the US population does not forget about other threats such as legionella as they return to work. In much of the past, following outbreaks or situations that give rise to Legionnaire’s, water utilities have recommended flushing out cooling towers and plumbing systems to eliminate the risk of bacterial buildup and then, prior to allowing reentry, perform readily available legionella testing through a local or regional water quality analytical lab. Yet it is unlikely that we will see much of the US building infrastructure flush their systems as the entire nation goes back to work. In a time of increasing concern surrounding water quality and quantity throughout the country, simply flushing a system, wasting thousands of gallons of water, and starting again seems at best, inefficient, and, at worst, wasteful.

The Sylmar team works with clients to implement new premise plumbing treatment systems as a solution both for short-term, post-COVID boot-up scenarios as well as long-term mitigation of the legionella threat in buildings. Building operators and treatment system integrators work with Sylmar and established technologies to set up systems within their own buildings to prevent harmful bacteria from ever forming in the first place. These solutions are not necessarily new – companies like Nalco have been installing systems to chlorinate, disinfect, and extend the life of cooling tower and HVAC equipment for decades9. And yet, novel ionization and filtration technologies have proliferated and decreased in costs over the past decade – leading to more efficient and cost-effective methods to provide individuals living and working in these buildings with a safe working environment. This new preventative method for legionella treatment – decentralized, resilient, sustainable – is the future of premise plumbing and legionella mitigation. For far too long our buildings have believed that the far away, centralized treatment plant will solve their water quality concerns. In many cases that may be true; with legionella, the new, decentralized way is the best way.

As COVID-19 opens our eyes as to how microorganisms can impact our lives in previously unforeseen ways, it is time that the water industry similarly begin to take seriously the potential for legionella to cause an outbreak of another kind. Sylmar works with technologies, companies, and utilities that seek to deploy proven, effective, and environmentally friendly systems to replace the inefficiency and wastefulness of simply trying to flush this problem away. Sylmar is here to help make 2020 not just a year of viral infection, but one in which we begin to think more holistically about the future of our relationship with our water and protecting our most vulnerable populations from the dangers of legionella is one step in that direction.