River Protection Information Sheet

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information on fish in the East and West Forks of the San Juan River can be obtained from the Colorado Division of Wildlife (CDOW). USFS-Identified Outstandingly Remarkable Values or "ORVs" As part of its evaluation of rivers for Wild and Scenic River (WSR) eligibility, the USFS analyzes rivers for any river-related values that are unique, rare, or exemplary, and that are significant on a regional or national scale. These features are identified as "Outstandingly Remarkable Values." What follows is a description of the ORVs for the East and West Forks taken from the San Juan Public Lands Center's 2007 Draft Land Management Plan: San Juan River East Fork—Geology San Juan River West Fork—Geology, The reach is valuable as a visible geologic Wildlife and Scenery "classroom" where people can see and study a The reach has geologic significance because phenomenon of planetary importance that is the dramatic events recorded in the rocks are so poorly understood today. This stream is a exposed and visible for study and appreciation textbook example in the San Juan Mountains by people. The river has carved through a of a multiple advance-and-retreat alpine complex of Tertiary Oligocene pyroclastics (ash glacial-fluvial system in a setting of recent flows, tuffs and lava flows) emplaced during the volcanic geology, ranging from sculpted creation of the San Juan Volcanic field, a time of headwaters through glaciated valley to narrow possibly the most violent volcanic explosions outwash canyons. There are abundant post- (caldera eruptions) of the last 4 billion years. glacial features, including braided stream Erosion by the river has left visible on the valley system, terminal and lateral moraines, the side walls exposures of massive layers of dramatic"gateway" entrance to the glacial pyroclastics and volcaniclastics that are valley, hanging valleys, and waterfalls. The textbook cross-sections of the distal zones of entire reach of the river is a document of the the San Juan Volcanic field in Colorado. Also in most recent planetary glacial age, which may the river valley, the post-glacial failure of not yet be over, through geologic terrain that support in the volcanic cliff walls has generated was fresh when the glaciation began and has massive ongoing landslides, classic examples been little altered since it ended. The valley's of slope failure, gravity slumping and colluvial dramatic glaciated and floodwater-carved movement, hosting outstanding groves of aspen landscapes have attracted recreational use which thrive on such disturbed ground. and development proposals since the • Recreational driving and hiking benefit from the settlement of this part of the state. colorful exposures of volcanic ash, which rival The importance of this ORV, according to the those of Yellowstone National Park's Little USFS, is that people can view and experience Grand Canyon. the geology because of its accessibility. The importance of this ORV, according to the USFS, is that people can view and experience the geology because of its accessibility. The Wolf Creek and Falls Creek Areas were found to be eligible for WSR because of the ORVs of wildlife and scenery. The Wolf Creek and Falls Creek branched segment contains five waterfalls occupied by nesting black swifts, a bird of conservation concern. Black swifts will nest only at waterfalls, and the species'world- wide breeding distribution is limited to a narrow portion of the Rocky Mountains from Mexico to Canada, and another small band encompassing sea cliffs along the Pacific coast from California to Alaska. The area contains a core breeding population of the bird and provides population and habitat connectivity to the southern portion of the species' range. Treasure Falls, on Falls Creek and just off Highway 160, is one of the easiest waterfalls to 3 visit within the San Juan Public Lands. It is visited by people from all over the world.