Wildfires can leave surviving homes and their water unsafe – safety tips for residents as they return

Following a wildfire, evacuated residents often mistakenly believe that simply receiving an "all clear" order means it is time to return to their homes and resume normal life. However, the truth is that homes may be safe on the surface but still harbor dangerous pollutants inside. As an environmental engineer with experience in wildfire recovery, I have witnessed this cycle play out repeatedly in communities impacted by some of the most devastating blazes in U.S. history.

When it's safe to return, the first order of business should be to get the home inspected by a professional. Smoke, toxic ash, and chemicals emitted by burning buildings and vehicles can infiltrate through windows, vents, and HVAC systems, settling in walls, carpets, furniture, clothing, and toys – virtually everywhere. These contaminants may include lead, which can impair lung function and brain development in children; arsenic and asbestos, both of which are linked to cancer and respiratory damage; and volatile or semi-volatile organic compounds (VOCs) that can harm internal organs.

Even if the building seems unharmed, the only reliable way to determine whether it's contaminated is through a thorough professional inspection. This should cover all living spaces, attics, crawlspaces, garages, HVAC systems, ductwork, and indoor surfaces. Special tests can identify lead and other metals, while indoor air samples can reveal volatile organic compounds. Asbestos is particularly concerning, as wind and debris can transport it to areas where it was previously absent.

Once contamination is confirmed, remediation work must be carried out by certified professionals, followed by independent confirmation testing. Anyone involved in restoration must use protective equipment and follow safe practices to avoid exposure to hazardous substances. It's crucial to remember that assuming drinking water is safe simply because the faucet works is a common mistake. Fires can damage plumbing systems, allowing smoke, debris, and contaminated air to enter pipes.

Chemical hazards in water systems may include benzene, a known carcinogen, which has been detected in plumbing after fires. Boiling water does not remove these toxins and may even increase exposure by releasing them into the indoor air. Utilities are generally responsible for testing and repairing infrastructure up to the property line, while property owners must then ensure the safety of their own plumbing, water heaters, irrigation systems, and private wells. Even if utility water is declared safe, contamination can persist inside the building.

To address potential water contamination, residents may need to rely on bottled water for drinking, cooking, and bathing. In rural and agricultural areas, similar precautions are needed for water tanks, troughs, and irrigation lines damaged by the fire. By taking these essential safety precautions after a wildfire, residents can protect themselves and their families from the hidden dangers that often accompany these devastating events.