Wildfires threaten drinking water as ash and chemicals pollute watersheds

Wildfires are increasingly compromising U.S. water systems, introducing toxins from burned forests and damaged infrastructure into reservoirs and household supplies.

Daniel Wolfe and Aaron Steckelberg report for The Washington Post.


In short:

  • Over 60% of the U.S. drinking water supply comes from forested areas vulnerable to wildfire contamination.
  • Post-fire runoff containing ash, debris and dissolved organic matter can overwhelm reservoirs, increasing toxic algae blooms and water treatment challenges.
  • Damaged water systems, including melted plastic pipes, can release volatile organic compounds (VOCs), contaminating residential water supplies long after fires are extinguished.

Key quote:

“We’re destabilizing [water] systems and we don’t even know in what way and how.”

— Newsha Ajami, chief strategic development officer for research in the Earth and Environmental Sciences Area at Lawrence Berkeley National Labs

Why this matters:

Megafires are burning larger areas and releasing more harmful materials, straining water treatment systems and exposing millions to potential toxins. Communities must adapt by investing in fire-resilient infrastructure and proactive water safety measures to address worsening fire seasons fueled by climate change.

A rustic outhouse with a crescent moon in the door

The world ditched wasteful toilets, the US stayed behind

US toilets use far more water than many of their global counterparts. President Donald Trump is pushing to loosen water pressure standards, a move critics say would increase waste.
A person kicking a soccer ball into a goal

The 2026 men’s World Cup could be the dirtiest ever

The sprawling North American tournament could generate 9 million metric tons of climate-warming pollution, a report found.
A row of wind turbines on dry hills

Wyoming electric utility dumps wind and solar in long-term planning

PacifiCorp’s previous upward trajectory for renewable energy will flatline beyond 2027 while its forecasted greenhouse emissions will rise.

A red, white and green Hungarian flag waving in the wind

Hungary election promises renewable energy investment and foreign factory crackdowns

Orbán, who once described EU climate ambitions as a 'utopian fantasy', has been replaced by Péter Magyar.
A wind turbine towering over a forest

Blowin’ in the wind: how Nordic countries made electricity free

As wind and hydropower flood Nordic grids, electricity prices are plunging and offering a glimpse of a cheaper energy future.
A person sitting in front of a woodstove

Does burning wood actually fight climate change?

Despite industry claims, scientists say using wood pellets is little better than fossil fuels.
A view of a large petrochemical plant with the sunset in the background

Iran war exposes dependence on petrochemicals

Disruptions from the Iran war are exposing how deeply petrochemicals — made from fossil fuels — are embedded in everyday products and global supply chains.

From our Newsroom
Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

One facility has emitted cancer-causing chemicals into waterways at levels up to 520% higher than legal limits.

Regulators are underestimating health impacts from air pollution: Study

Regulators are underestimating health impacts from air pollution: Study

"The reality is, we are not exposed to one chemical at a time.”

Pennsylvania governor Josh Shapiro speaks with the state flag and American flag behind him.

Two years into his term, has Gov. Shapiro kept his promises to regulate Pennsylvania’s fracking industry?

A new report assesses the administration’s progress and makes new recommendations

silhouette of people holding hands by a lake at sunset

An open letter from EPA staff to the American public

“We cannot stand by and allow this to happen. We need to hold this administration accountable.”

wildfire retardants being sprayed by plane

New evidence links heavy metal pollution with wildfire retardants

“The chemical black box” that blankets wildfire-impacted areas is increasingly under scrutiny.

Stay informed: sign up for The Daily Climate newsletter
Top news on climate impacts, solutions, politics, drivers. Delivered to your inbox week days.