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 view of solar panels with wind turbines and mountains in the background

Clean energy saved EU €51 billion in 2025 by cutting fossil fuel imports

Investing in renewables has ensured greater energy security at a moment when the war on Iran is destabilizing supplies and forcing up costs.

Wall-mounted power storage unit - whole-house battery concept

The household battery revolution that could change energy bills … and the world

Australia is pioneering a revolution in home renewables and battery use, proving what is possible with the right policies.

A view of a rocky wilderness with trees and boulders

Feds to open tens of thousands of acres of Colorado wilderness to oil drilling

A federal agency will offer tens of thousands of acres in northwestern Colorado that the nation’s largest elk herd relies upon for migration, foraging and winter habitat to oil and gas companies.

Financial graph superimposed against a "Wall Street Bro"

SEC proposes to kill climate change disclosure rule

The regulation would have required all publicly traded companies to disclose whether they faced significant risks from climate change and its effects.
Coal-burning power plant emitting air pollution against an orange sky
Credit: Faux Toe/BigStock Photo ID: 1366970

Virginia, Maryland craft stricter coal ash rules as EPA pulls back

The U.S. Environmental Protection Agency this spring proposed loosening environmental regulations on dump sites for coal ash, aiming to meet the energy industry’s request for more flexibility.

A view of a flooded street

Opinion: Climate rollbacks risk Marylanders first

Climate change is not some distant, future threat, it's being felt now all across Maryland, which is why the federal government's decision to do away with the endangerment finding needs to be fought.

Coral reef with some corals showing evidence of bleaching and surrounded by fish

Coral reefs in French Polynesia are stuck between life and death

Scientists’ discovery of hollowed coral skeletons after a 2019 bleaching event reveals a reef that isn’t coming back.
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.