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The Trump administration is moving forward with a proposal that would redefine which waterways in America get federal protection. Many industry groups felt that the previous definition was too broad. NPR's Nathan Rott went to New Mexico, a state that's bracing for significant change. He sent this report.
NATHAN ROTT, BYLINE: For most of you river-goers out there, the Santa Fe...
(SOUNDBITE OF BIRD CHIRPING)
ROTT: ...Would not be much to look at or play in. You'd be lucky if you could float a soda can down it. Though looking at its brush-tangled banks in downtown Santa Fe, it looks like a few people have tried. Its springtime runoff is more trickle than torrent. But to folks like Rachel Conn, this is impressive.
RACHEL CONN: This is, like, flow in New Mexico. This is - a lot of creatures depend on something like this.
ROTT: Conn is with Amigos Bravos, New Mexico-based conservation group that focuses on water issues.
CONN: Up to 94 percent of our waters are these smaller types of waters that flow only part of the year. But they all drain into our bigger systems. And it is from these bigger systems that close to 300,000 New Mexicans receive their drinking water.
ROTT: And it's these types of smaller rivers and streams that may soon lose federal protections. The Trump administration's new proposed definition of which waters should fall under the Clean Water Act does not include ephemeral or intermittent streams - waterways that only flow after precipitation like the Santa Fe, or, say, every other year, which isn't all that uncommon in the arid Southwest. That means industry or landowners looking to discharge wastewater into one of those or dam one of those streams would no longer need a federal permit to do so.
HELEN NEVILLE: So it's millions of miles of stream.
ROTT: Helen Neville is the senior scientist for the conservation and sportsmen's group Trout Unlimited, an organization that opposes the new rule. The Environmental Protection Agency estimates that about 18 percent of streams nationwide and half of the country's wetlands would no longer be considered waters of the United States under the president's proposal. Trout Unlimited believes it's far more because ephemeral streams are so hard to map and so easily overlooked.
NEVILLE: You know, it's very similar to how you think about your capillaries feeding your blood vessels.
ROTT: Ephemeral streams may seem insignificant.
NEVILLE: But they're critically important for the health of those downstream waters just like your capillaries are critically important for the health of your blood system.
ROTT: And she says that's especially true in the southwest, where rains can be few and far between. Even the Rio Grande, New Mexico's biggest river, ran dry in parts last year. Chad Smith, CEO of the New Mexico Farm and Livestock Bureau, is less worried about the impact on the state's waterways and doesn't believe that it will lead to a surge in pollution from industries like his, something environmental groups have warned about.
CHAD SMITH: We want to make sure our waterways are clean. We want to make sure we protect our natural resources that we make a living off of.
ROTT: He says industry groups around the country are applauding the proposed change.
SMITH: It couldn't be more welcomed. I think what it does from a very high-level perspective is it provides some more clarity and certainty for farmers and ranchers across the landscape.
ROTT: Clarity and certainty are the reasons the Trump administration is giving, too. The EPA says they want to make it clear for landowners and developers whether federal laws apply to a project or not. Conflicting court decisions have made that muddy in the past. And it's likely that courts will get another say about this change. Nathan Rott, NPR News, Santa Fe, N.M. Transcript provided by NPR, Copyright NPR.