READ MORE about the Yampa River, which C&K identified as one of the world’s most threatened paddling runs for 2015.

What happens when a new rapid forms overnight? What’s it like to suddenly find a bus-eating hole in a stretch of calm river you’ve run dozens of times? These are some of the questions behind Rig to Filp Productions‘s new mini-documentary Warm Springs.

Named after a rapid on the Yampa River in northwestern Colorado that was formed by a landslide nearly 50 years ago and drowned a rafter, Warm Springs is also an account of the last free-flowing river in the Colorado River basin. A roaring Class IV+ cataract during spring runoff but little more than a creek by late summer, Warm Springs Rapid is one of the few places in the West that still goes through seasonal rhythms without interference from large-scale reservoirs thanks to a successful 1950s campaign that blocked construction of the Echo Park Dam.

Warm Springs starts with the exciting story of a single rapid and becomes a look at the river conservation movement in general; the film reminds us why wild rivers matter — and all in 20 minutes. It’s well worth the watch.

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