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Hotchkiss before converging with the main stem of the Gunnison River north of the Gunnison <br />Gorge and the Black Canyon of the Gunnson National Park. The headwaters begin at the <br />confluence of Anthracite Creek and Muddy Creek in the Gunnison National Forest at an <br />approximate elevation of 6200 feet. The river flows 33 miles in a southwestern direction through <br />a valley of multiple river terraces positioned laterally along a highly dissected broad valley with <br />gentle down-valley slope. <br />The North Fork of the Gunnison River drainage is located on the western edge of the Rocky <br />Mountain uplift. The geology of the watershed is a complex mix of sedimentary formations, <br />primarily Mancos shales and the mixed Mesa Verde and Wasatch formations that have been <br />uplifted by the Rocky Mountain orogeny and intn~ded by a variety of igneous materials. These <br />sedimentary materials are young geologically and loosely consolidated causing a high erosivity <br />and producing high sediment loads. The majority of these lands are considered sensitive to very <br />sensitive to disturbance due to geology and slope. <br />The North Fork of the Gunnison River is a 4ti' order perennial stream channel with seasonal <br />variations in streamflow dominated primarily by snowmelt n~noff. The USGS hydrologic unit <br />code is 14020004. Flows increase from approximately 50 cfs in late summer to a range of 2000 <br />to 5000 cfs during May and June at peak runoff. The highest peak flow on record was 9220 cfs in <br />1984 at the gage in Somerset. The mean annual high water runoff is approximately 3200 cfs. <br />The dominant stream types (Rosgen Classification) in the priority reaches between Paonia and <br />Hotchkiss are C-3 and D-3. The North Fork of the Gunnson River is listed as a Category 1 in <br />the Uiufied Watershed Assessment and recognized in the Colorado Nonpoint Assessment Report <br />as a contributor of sediment and selenum to the Colorado River system that includes prime <br />habitat for endangered fish. Sediment and selenium is the primary pollutant of this impaired <br />stream segment. <br />Land use within the watershed is approximately 94% forest and 4% agriculture. Land ownership <br />within the project location is 100% private with the primary land use being agricultural. <br />Issues The North Fork of the Guiulison Basin segment 3 (which contains the project site) is <br />identified as having chronic selenium concentrations exceeding in-stream water quality standards <br />as adopted in the Classifications and Numeric Standards for the Gunnson and Lower Dolores <br />River Basins (Regulation No. 35). Selenium is a naturally occurring element conu7loi~ly found in <br />Mancos shale formations typical to the North Fork Basin and surrounding areas. It is released in <br />toxic amounts to the river primarily by irrigation n~noff and bai~lc erosion. Decades of bulldozing <br />in the river and removal of riparian buffers have increased selenium and nutrients concentrations, <br />such as phosphates and nitrates, by substantially increasing bai~lc erosion and direct nuloff to the <br />river. Results from water quality monitoring following storm runoff events closely correlates <br />with increases in turbidity and total suspended solids with phosphates and selenium. <br />The Watershed Restoration Action Strategy of the North Fork of the Gunnison River was <br />completed in November 2000 and developed as a living document to guide the actions of the <br />North Fork River Improvement Association. The document is available in electronic format from <br />the Association. The document is periodically updated at strategic planiung sessions. Goal 2 of <br />