Prepared for Federal Action Agency U.S. Fish and Wildlife Service U.S. Army Corps of Denver, Colorado Engineers Project Proponent _______________________ o Denver Water Fish and Wildlife Coordination Act Report Moffat Collection System Project _______________________ October 4, 2016 Prepared by URS Corporation 6200 South Quebec Street Greenwood Village, CO 80111 Contents 1. EXECUTIVE SUMMARY ............................................................................................................... 1 2. INTRODUCTION ............................................................................................................................. 3 2.1 Purpose, Scope, and Authority .................................................................................................. 3 2.2 Relevant Prior Studies, Reports, and Previous Consultation ..................................................... 4 3. DESCRIPTION OF THE STUDY AREA ...................................................................................... 7 3.1 Reservoirs ................................................................................................................................ 13 3.2 Other Facilities ........................................................................................................................ 17 3.3 River Segments........................................................................................................................ 17 3.3.1 Fraser River ................................................................................................................ 18 3.3.2 Williams Fork River ................................................................................................... 19 3.3.3 Colorado River ........................................................................................................... 20 3.3.4 Blue River .................................................................................................................. 21 3.3.5 South Boulder Creek .................................................................................................. 21 3.3.6 North Fork South Platte River .................................................................................... 22 3.3.7 South Platte River ....................................................................................................... 22 4. FISH AND WILDLIFE CONCERNS AND PLANNING OBJECTIVES ................................. 25 4.1 Aquatic Resources ................................................................................................................... 25 4.1.1 Study Area .................................................................................................................. 25 4.1.2 Regulatory Framework ............................................................................................... 25 4.2 Wildlife Resources .................................................................................................................. 26 4.2.1 Study Area .................................................................................................................. 26 4.2.2 Regulatory Framework ............................................................................................... 26 4.3 Vegetation Resources .............................................................................................................. 27 4.3.1 Study Area .................................................................................................................. 27 4.3.2 Regulatory Framework ............................................................................................... 27 5. EVALUATION METHODS .......................................................................................................... 29 5.1 Hydrologic Modeling .............................................................................................................. 29 5.2 Aquatic Resources ................................................................................................................... 34 5.2.1 Habitat Simulation Methods ....................................................................................... 34 5.2.2 Approach to Impact Analysis ..................................................................................... 37 5.3 Wildlife Resources .................................................................................................................. 39 5.4 Vegetation Resources .............................................................................................................. 39 6. FISH AND WILDLIFE RESOURCES – CURRENT CONDITIONS ....................................... 41 6.1 Aquatic Resources ................................................................................................................... 41 6.1.1 Gross Reservoir .......................................................................................................... 41 6.1.2 Other Project Facilities ............................................................................................... 42 6.1.3 Fraser River ................................................................................................................ 42 6.1.4 Williams Fork River ................................................................................................... 49 6.1.5 Colorado River ........................................................................................................... 52 6.1.6 Blue River .................................................................................................................. 53 6.1.7 South Boulder Creek .................................................................................................. 54 6.1.8 North Fork South Platte River .................................................................................... 55 6.1.9 South Platte River ....................................................................................................... 55 i 6.2 Wildlife Resources .................................................................................................................. 57 6.2.1 Federally-Listed Threatened and Endangered Species ............................................... 57 6.2.2 State Threatened and Endangered Species and Species of Special Concern ............. 59 6.2.3 USFS Species ............................................................................................................. 61 6.2.4 CNHP Species ............................................................................................................ 62 6.2.5 Big Game .................................................................................................................... 63 6.2.6 Other Wildlife ............................................................................................................ 63 6.2.7 Raptors and Other Migratory Birds ............................................................................ 64 6.2.8 USFS Management Indicator Species and Wildlife Habitats ..................................... 64 6.2.9 Sensitive Areas ........................................................................................................... 64 6.3 Vegetation Resources .............................................................................................................. 65 6.3.1 Federally-Listed Threatened and Endangered Species ............................................... 65 6.3.2 USFS Species ............................................................................................................. 67 6.3.3 CNHP Species ............................................................................................................ 69 6.3.4 Vegetation Cover Types ............................................................................................. 69 6.3.5 Plant Communities of Concern .................................................................................. 74 6.3.6 Noxious Weeds .......................................................................................................... 74 7. FISH AND WILDLIFE RESOURCES – FULL USE OF THE EXISTING SYSTEM WITH RFFAS.................................................................................................................................. 77 7.1 Aquatic Resource Impacts ....................................................................................................... 77 7.1.1 Depletion of Strategic Water Reserve Strategy .......................................................... 77 7.1.2 Combination Strategy ................................................................................................. 80 7.2 Wildlife Resources Impacts ..................................................................................................... 80 7.3 Vegetation Resource Impacts .................................................................................................. 81 8. DESCRIPTION OF ALTERNATIVES ........................................................................................ 83 8.1 Development of Alternatives ................................................................................................... 83 8.2 Description of Alternatives ..................................................................................................... 84 8.2.1 Proposed Action (Alternative 1a) ............................................................................... 84 8.2.2 Alternative 1c ............................................................................................................