Fire and Water in the Western United States

Wildfires in the western United States are increasing in size and severity due to climate change and historical fire suppression, posing significant risks to water resources. High-severity fires destroy vegetation and alter soil chemistry, leading to increased streamflow, flooding, and the contamination of drinking water with sediments, toxins, and carcinogens. The document advocates for a combination of emissions reductions, active forest management—including prescribed and Indigenous cultural burns—and investments in climate-resilient water infrastructure to mitigate these threats.

• Wildfires disrupt the natural filtration and regulation services of watersheds, where plants stabilize soil and soils absorb pollutants, leading to impacts on water quality and availability that can persist for years or decades.
• High-severity wildfires can kill over 90 percent of vegetation, removing the root systems that stabilize soil and absorb water, which increases streamflow and heightens the risk of flooding, landslides, and debris flows.
• Wildfires degrade water quality by making soil water-repellent, which increases the runoff of sediments and nutrients like nitrogen and phosphorus into freshwater systems, potentially causing toxic algal blooms.
• The burning of human infrastructure, such as cars and homes, releases toxic compounds and carcinogens into water supplies; additionally, water pipes not designed for high temperatures can fail and contaminate distribution networks.
• Climate change and a century of intentional fire suppression have increased wildfire frequency and severity in the West, with human-caused warming linked to a near doubling of the area burned by US wildfires between 1984 and 2015.
• Proactive forest management, including thinning, prescribed burns, and the reintroduction of Indigenous cultural burns, can reduce fuel loads and limit soil heating, thereby protecting water resources from the effects of high-severity fires.
• Adapting water infrastructure to be more climate-resilient involves diversifying water sources, installing sediment barriers, scaling up sediment removal capacity, and mandating heat-resistant pipes in new construction.

APA

Union of Concerned Scientists (2022). Fire and Water in the Western United States. https://www.ucs.org/sites/default/files/2022-06/fire-water-western-us.pdf

Chicago

Union of Concerned Scientists. Fire and Water in the Western United States. 2022. https://www.ucs.org/sites/default/files/2022-06/fire-water-western-us.pdf.

Wikipedia

{{cite report |author=Union of Concerned Scientists |title=Fire and Water in the Western United States |date=June 2022 |url=https://www.ucs.org/sites/default/files/2022-06/fire-water-western-us.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{unionofconcernedscientists2022fire, author = {{Union of Concerned Scientists}}, title = {{Fire and Water in the Western United States}}, institution = {Union of Concerned Scientists}, year = {2022}, month = jun, url = {https://www.ucs.org/sites/default/files/2022-06/fire-water-western-us.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }