Oregon coastline
The rugged waters off Oregon are turning acidic.
Daniel Powell

Carbon emissions are turning seawater acidic, and environmentalists say that’s a violation of the Clean Water Act.

The Center for Biological Diversity filed a lawsuit Wednesday against the EPA, challenging the agency’s assertion that the increasingly acidic ocean off Oregon and Washington meets federal water-quality standards.

Perhaps a quarter of the carbon dioxide that we pump into the air mixes into the sea, where it reacts with water to produce bicarbonate. The byproducts of these reactions are loose hydrogen atoms, which lower the marine pH. The concentration of hydrogen ions in surface ocean waters has risen 26 percent since the Industrial Revolution, reducing pH levels by 0.1 unit.

Rising ocean acidity has hit the Pacific Northwest hard, and local shellfish hatcheries have been in crisis since 2005. That’s because the deep near-coastal waters experience extensive upwelling — in which waters rise and sink, carrying minerals and nutrients up and down like elevators. Strong upwelling zones off Chile and southern Africa are also being severely affected by acidification.

The Center is arguing in federal court that the acidic waters of Oregon and Washington should be defined by the EPA as impaired. If that were to happen, new pollution control measures may be required to repair the water quality, potentially prompting greater government urgency in clamping down on greenhouse gas emissions.

This is not the first time that the Center has taken such action. From EarthFix:

The Center for Biological Diversity filed a similar lawsuit in 2009. Back then, the EPA agreed with the center and determined that it should address acidification under the Clean Water Act.

But the environmental group says the EPA has not taken the necessary actions since then.

“We need fast action to save marine diversity, because when the harm of ocean acidification deepens we’ll realize how much we all depend on the ocean,” Miyoko Sakashita, the Center’s oceans director, said in a statement. “The Pacific Northwest is among the places getting hit hardest at the outset of this crisis. Although some state officials in Washington are taking it seriously, we need the EPA and the Clean Water Act to truly begin addressing it on a broader scale.”