Science publishes EDF analysis warning up to 90 million acres of wetlands may now be at risk

(New York, NY) - New peer-reviewed analysis by Environmental Defense Fund (EDF), published by Science, reveals that millions of acres of critical wetland habitat have lost vital protections in the wake of a 2023 Supreme Court of the United States majority opinion (Sackett v EPA) that drastically narrowed the scope of wetlands protected under the Clean Water Act. 

The analysis shows that 17 to 90 million acres of wetlands in the contiguous U.S, a range that is based on how the Court’s decision could be interpreted, have lost federal protections. For reference, 90 million acres is about the size of Montana. The decision is compounded by the fact that many states have few or no state-level wetlands protections, with 24 states relying entirely on federal protections via the Clean Water Act and therefore potentially leaving wetlands without any protection at all.   

“Wetlands provide important wildlife habitat, clean water and significant flood risk reduction,” said Dr. Adam Gold, a scientist with EDF’s Climate Resilient Coasts and Watersheds program. “Rolling back federal wetlands protections will make it harder to conserve these critical ecosystems. This new analysis demonstrates the uncertainty in federal wetlands protections going forward due to the Supreme Court’s ruling.” 

Prior to the majority opinion, the Supreme Court and lower courts upheld that wetlands that are connected to federal waterways, including those connected below the surface, such as through groundwater, should be protected. The Supreme Court opinion now states that wetlands must have “a continuous surface connection” to federal waters, an approach that is not grounded in science and establishes tremendous uncertainty as to how this will be interpreted in the long-term.    

Wetlands are pivotal in protecting communities from flooding, our nation’s costliest natural hazard, because they act as natural sponges that slow and absorb floodwaters, reducing downstream damages. With one acre of wetlands storing as much as 1.5 million gallons of flood water, continued loss of wetlands and development in high-risk areas will only exacerbate the impacts of climate change and put more communities at risk of flooding. Wetlands also clean our water and are home to 40% of the world’s species and 75% of commercially harvested fish and shellfish species in the United States.