New Guide Addresses Stagnant Water in Buildings with Low Occupancy

IAPMO water expert explains the importance of addressing water stagnation in low-occupancy buildings.

COVID has taken its toll on buildings. Work-from-home mandates have turned once-bustling office and multiuse complexes and other commercial structures into shuttered shells. Building owners have had to quickly pivot to new best practices to keep their structures safe and well maintained.

One of the most pressing issues is the danger posed by stagnant water. “COVID has resulted in buildings being closed for long periods of time, and for many of these, it is unprecedented,” says Peter DeMarco, executive vice president of Advocacy and Research at The IAPMO Group (International Association of Plumbing and Mechanical Officials). “Now you have water sitting in these places for many months with the potential for contaminants like legionella and metals. You have to get water moving and out of those structures, at a minimum.”

Walking through a building and flushing a few toilets is not the answer, according to DeMarco. “You don’t want to make a bad situation worse. If you don’t flush the water correctly you may actually distribute it [and disease] through the building unnecessarily.”

Guide for Stagnant Water Management

The good news is that there is professional guidance on how to manage stagnant water. Created by IAPMO and the American Water Works Association (AWWA), a guide called Responding to Stagnation in Buildings with Reduced or No Water Use is now available.

According to DeMarco, information on stagnant water exists, but it is problematic. “There are more than 60 guidance documents put out by various entities that all address this topic--with conflicting and sometimes inadequate guidance,” he says. “We have created one go-to document with AWWA which represents the voices of our two organizations because we want this to get serious attention.”

The guide offers precise recommended steps to help building owners to get fresh water in through the meter and flush it correctly throughout the system. According to DeMarco, many factors impact action steps, including:

• Age, size, and complexity of the building.
• Quality of the incoming water from the utility, especially residual disinfectant levels and the presence of contaminants or nutrients due to leaks in the distribution system.
• How the building is utilized, which can impact how water is used in the building and the extent immunocompromised people are exposed to the building’s water systems.
• Size and types of plumping pipes.
• At-risk population considerations.

Legionella: A Killer Waiting In Quiet Plumbing Pipes

DeMarco paints a grim picture of the risks of stagnant water, even in buildings that have been vacant for only several weeks.

Picture an old building with an owner unaware of water health. He takes no action to exhaust water in his semi-vacant building. The old plumbing materials, which have degraded over time, offer nutrients for pathogens, while pressure changes have knocked loose heavy metals. Legionella blossoms throughout the pipes.

“Folks can get seriously ill from legionella,” DeMarco emphasizes. “It is the biggest risk, and it is scary because it manifests as COVID-19 respiratory illness. Legionella is a bacteria but has the same type of symptoms as pneumonia, which could lead to misdiagnosis as COVID.”

The pandemic and recession will result in many commercial buildings changing hands over the next few years. The information contained in this guide is crucial for investors who aren’t familiar with the issues of low- or no-occupancy buildings. “If someone is buying a multifamily building that has been sitting for a while, they need to know that they must take action to maintain safe water. This guide gives them the information they need to do it right.”