News Feature | October 9, 2023

Rising Groundwater Could Release Toxic Chemicals From More Than 100,000 Contaminated Sites Across U.S.

Peter Chawaga - editor

By Peter Chawaga

Peter Chawaga

Researchers have uncovered a new climate-induced threat that could imperil thousands of water systems across the country, introducing harsh contaminants left in soil by industrial facilities into the influent that passes through drinking water treatment facilities.

“A little-known climate threat lurks under our feet: rising groundwater that could release toxic chemicals from more than 132,000 contaminated sites in coastal areas of the U.S.,” Bloomberg reported. “When groundwater rises toward the surface, whether from sea level rise or increasingly intense climate-driven storms, those contaminants can leach into it and spread to other waterways, potentially poisoning people and wildlife.”

Drinking water and wastewater treatment facilities are no strangers to climate change-induced obstacles. Drier weather has introduced drought conditions throughout the nation, growing wildfires have devastated water infrastructure, and toxic algae is growing in source water at alarming rates, just to name a few.

Now, highlighting a lesser-known water threat, researchers have mapped the areas most likely to see their groundwater inundated with industrial pollutants as sea levels continue to rise. Making matters worse, the researchers believe some of the volatile organic compounds in the soil can vaporize and enter homes through buried wastewater infrastructure.

In the Bay Area, for instance, pollution introduced by rising groundwater can put thousands of areas at risk.

“A new report finds that over the next century, rising groundwater levels in the San Francisco Bay Area could impact twice as much land area as coastal flooding alone, putting more than 5,200 state- and federally-managed contaminated sites at risk,” according to Berkeley News. “Many of these sites are near communities already burdened with high levels of pollution.”

But even as more attention turns to this emerging source of contamination, this climate-driven water issue will have to compete for resources already dedicated to so many others. Even as we only begin to understand the drinking water and wastewater issues this contamination could pose, it’s clear that solving them won’t be an easy task.

“Climate-related groundwater rise can scramble the calculus on cleaning up toxic sites,” per Bloomberg. “Rehabilitating these locations can drag on for years, if not decades, and the high cost of removing soil has resulted in it being left in place at many sites, covered by an impermeable clay or concrete cap meant to contain the contamination.”

For more information, about how water systems confront source water contamination visit Water Online’s Source Water Contamination Solutions Center.