JUANA SUMMERS, HOST:
In 2023, the U.S. Supreme Court dramatically limited the scope of the Clean Water Act. More than a year later, it's still unclear what rivers, streams and wetlands no longer have federal protections. A new study in the journal Science tackles part of that question. NPR's Nathan Rott joins us now to talk about what it found. Hey, Nate.
NATHAN ROTT, BYLINE: Hey.
SUMMERS: So, Nate, tell us about this new study.
ROTT: Right. So this study focuses specifically on the country's wetlands - places that are saturated or covered by water - so, you know, think like a marsh or a squishy mountain meadow.
SUMMERS: The kind of places I'd want to wear rubber boots, it sounds like.
ROTT: Exactly. Yeah. So scientists often call wetlands nature's sponges because they can absorb and store floodwaters, which is one of the many benefits we people get from wetlands. But since the Supreme Court decision last year, in a case called Sackett v. EPA, which was brought by homeowners in Idaho who had filled a wetland on their property, it's been really unclear for developers, for federal and state agencies and for ecologists which wetlands still have federal protections. Here's Adam Gold, an ecologist with the Environmental Defense Fund, who's the lead author of this new study.
ADAM GOLD: So we heard a few kind of initial estimates that, like, half of wetlands in the U.S. could have lost federal protections or are now without federal protections. But in reading the Sackett decision and talking with a bunch of really smart environmental lawyers, what really popped out to us was the just extreme uncertainty in the actual opinion itself.
ROTT: And that's because a bunch of the terms in the opinion, Gold says, are just really vague and subjective. So, for example, it says a wetland has to be indistinguishable from a major water body to be protected.
SUMMERS: What does indistinguishable mean exactly?
ROTT: (Laughter) Juana, that is a very good question. It's a new term in this context. And, you know, maybe a trained wetland ecologist who's looked at how water is moving from a wetland to a river - they might look at this and say, yeah, no doubt, this is indistinguishable. But a home builder or even a federal agency like the Army Corps of Engineers, which makes a lot of these decisions, they might interpret it differently. Nobody really knows yet, which is what Gold's study bore out.
GOLD: I estimated between 17 million acres and all the way up to 90 million acres of wetlands in the U.S. could be without federal protections based on the Sackett majority opinion.
ROTT: And for context, Juana, that high-end estimate, 90 million acres, is nearly every wetland in the lower 48 U.S. states.
SUMMERS: OK. This sounds like a big deal.
ROTT: Yeah.
SUMMERS: What does it mean if a wetland does not have federal protections?
ROTT: Well, that means it's much easier for a wetland to be developed or polluted. So if you're a homebuilder - right? - you don't have to get a federal permit to, say, fill in a wetland and build something on it.
So there might be state protections. And since the Supreme Court decision, we've seen some states strengthen their state water laws, but others have also weakened them. I talked to Marla Stelk, the executive director of the National Association of Wetland Managers, and she says there's been pressure from the development community in some states to weaken water laws to address the need for affordable housing.
MARLA STELK: Nobody disagrees that affordable housing is a huge need right now and extremely important. But if you're building affordable housing in wetlands, you're only putting those people who have the least ability to respond to repeat flooding in harm's way.
ROTT: Because those are places that water is obviously naturally drawn to. They're wetlands for a reason.
SUMMERS: Nate, is there any reason to believe, at some point, we'll get some clarity on this?
ROTT: You know, nobody really knows. There's already new lawsuits. Everyone I've talked to assumes it's only a matter of time before this comes up in the Supreme Court again. Alternatively, Congress could give clarity by passing a new water law. But given the reality - the political reality, I should say - that does not seem likely.
SUMMERS: That's Nathan Rott from NPR's Science Desk. Thank you.
ROTT: Yeah, thank you. Transcript provided by NPR, Copyright NPR.
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