Smoke and Water Don't Mix

Abstract

Wildfires in California have become more frequent and intense. Along with addressing the typical consequences of these natural disasters, two drinking water utilities discovered how to handle high levels of volatile organic compounds in their distribution systems as well as the physical and public relations effects of contamination.

Wildfire Induces Changes in Receiving Waters: A Review With Considerations for Water Quality Management

“…In addition to PAHs in runoff, fire can directly impact drinking water infrastructure in WUI urban areas, causing organic compound contamination. A recent paper reported benzene and other volatile organic compounds (VOCs) at concentrations 2–3 orders of magnitude above drinking water standards, likely caused by thermal degradation of plastic materials ( Macler et al, 2020 ). Fires in Santa Rosa, CA and Paradise, CA in 2017 and 2018, respectively, burned houses and melted plastic water service lines.…”

“…Benzene was detected at concentrations exceeding federal and state standards ( Table 2 ). Do not drink orders were issued, and contaminants sorbed to plastic pipes required flushing and, in some cases, wholesale infrastructure replacement to remedy ( Macler et al, 2020 ).…”

“…We identified one peer-reviewed study that found ash generated from residential and building materials had higher metal concentrations (e.g., arsenic, copper, lead, nickel, and zinc) than wildland ash ( Burton et al, 2016 ). A second set of articles described increases in benzene and other VOCs due to damaged pipes following two destructive wildland fires affecting WUI urbanized areas in California ( Macler et al, 2020 ; Proctor et al, 2020 ). No other study we found focused explicitly on the effects of these types of fires on endpoint responses.…”

“…Managers of public water supplies should be aware of the potential for post-fire contamination from these chemicals in particular. Physical damage from fire is also a threat to drinking water infrastructure, such as the cases observed in California ( Macler et al, 2020 ). Areas in the fire-prone WUI may need to consider mitigation measures, such as backflow preventers to keep contaminants from burning infrastructure out of drinking water distribution systems.…”