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The next story is about a conundrum at Conundrum Hot Springs in Colorado. And it's become quite a destination - a place to take in nature and hang out in warm water, elbow to elbow with a bunch of naked people. There's loud music, drinking and general mayhem. The U.S. Forest Service says it's all threatening the fragile ecosystem. And as Luke Runyon of member station KUNC reports, rangers are starting to crack down.
LUKE RUNYON, BYLINE: OK, so I'm up here at Conundrum Hot Springs, just about to walk up to the hot springs. It's a Saturday night. Dark out, probably about 10:00. The stars are shining overhead. It's beautiful. You can smell a little bit of the sulfur smell on the wind. That's the hot springs. And, of course, you can hear the people.
JEREMY BOOKMAN: I've heard about Conundrum for, like, years and years. I always wanted to do it.
RUNYON: Jeremy Bookman is up here from Boulder. He made the long trek to the springs lugging gear above 11,000 feet in elevation.
BOOKMAN: And it's just legendary - you know? - to do, like, an overnight to a hot springs this deep into the mountains.
RUNYON: Now, just to set the scene, Bookman's one of a couple dozen people soaking in the pool tonight. Most are nude. They're passing around bottles of booze. There's a bachelor party. Bookman says he first thought he might luck out, get a weekend of solitude in the mountains. Who else wants to backpack nine miles uphill?
BOOKMAN: When I started checking for directions, you know, I started Googling it and getting some images about, like, a full pool. And I knew it. Of course everyone's going to want to do this.
ERIC TIERNEY: It's incredibly beautiful up here. It's remote.
RUNYON: Eric Tierney is a wilderness ranger with the U.S. Forest Service, which manages the area.
TIERNEY: And somewhere along the line, it just kind of started to attract a - more of a party crowd.
RUNYON: On weekends in the summer and fall, upwards of 300 people pack into this tight valley.
TIERNEY: Even tonight, it's just like, where are we going to put everyone?
RUNYON: Conundrum's always been popular, but as it's shown up more on the pages of glossy outdoor magazines and in thousands of Instagram posts, the crowds have swelled. In the last 10 years, visitation has increased four-fold. Tierney has the unenviable task of being both rule enforcer and housekeeper. Last year alone, rangers packed out more than 500 pounds of garbage. Revelers at the springs will sometimes abandon whole campsites in the wilderness, leaving rangers like Tierney to clean up the mess.
TIERNEY: Our packs get heavier as we go because we're always packing up trash.
RUNYON: Not to mention the effects to the fragile alpine ecosystem. Campers are stripping trees to build illegal campfires and setting up tents on wildflower meadows. In years past, the pool has tested positive for bacteria found in human feces.
SLOAN SHOEMAKER: When you go to Conundrum, it's like going to a rave, you know, on a Fourth of July weekend or a Labor Day weekend.
RUNYON: Sloan Shoemaker runs Wilderness Workshop, a Colorado-based non-profit that advocates for wilderness areas.
SHOEMAKER: It seems pretty clear that the only solution is to somehow restrict access or to limit access.
RUNYON: And that's exactly what the Forest Service is trying to do. The agency has started looking at limiting the number of visitors to Conundrum as early as next summer.
Back at the hot springs, Jeremy Bookman says the Forest Service should crash the party. He came up on a whim. Under a permit system, he wouldn't be able to be as spontaneous. And that's OK with him.
BOOKMAN: Yeah, it would be inconvenient, but it would also make it all that more special.
RUNYON: And as Colorado's population continues to boom, it'll be that much harder to keep its wild places from losing what makes them special in the first place. For NPR News, I'm Luke Runyon at Conundrum Hot Springs. Transcript provided by NPR, Copyright NPR.