Final Environmental Assessment Project No. 2016-073 Resource Management Plan for Horsetooth Reservoir Carter Lake Pinewood Reservoir Flatiron Reservoir United States Department of the Interior Bureau of Reclamation, Great Plains Region Eastern Colorado Area Office September 2018 i MISSION STATEMENTS The mission of the Department of the Interior is to protect and provide access to our Nation’s natural and cultural heritage and honor our trust responsibilities to Indian Tribes and our commitments to island communities. The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. ii Table of Contents ACRONYMS ................................................................................................................................. v INTRODUCTION......................................................................................................................... 1 PURPOSE AND NEED ................................................................................................................ 1 BACKGROUND ........................................................................................................................... 3 ALTERNATIVES ......................................................................................................................... 5 NO ACTION ALTERNATIVE ........................................................................................................................ 5 PROPOSED ACTION .................................................................................................................................. 5 AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES ................ 10 Hydrology and Water Quality ................................................................................................................ 16 Geology, Soils, and Topography ............................................................................................................ 19 Vegetation and Fire Management ......................................................................................................... 21 Fish and Wildlife ..................................................................................................................................... 28 Federally Listed Species ......................................................................................................................... 30 Colorado Special Status Species ...................................................................................................... 31 Recreation .............................................................................................................................................. 36 Visual ...................................................................................................................................................... 45 Land Use ................................................................................................................................................. 48 Public Facilities and Transportation ...................................................................................................... 50 Socioeconomics ...................................................................................................................................... 54 Cultural Resources .................................................................................................................................. 56 Paleontological Resources ..................................................................................................................... 58 Other Resources ..................................................................................................................................... 59 SUMMARY OF ENVIRONMENTAL EFFECTS .................................................................. 60 CONSULTATION AND COORDINATION ........................................................................... 64 Scoping Process and Public Comment ................................................................................................... 65 Agency Coordination .............................................................................................................................. 66 REFERENCES ............................................................................................................................ 68 iii List of Tables Table 1-Total Area of New Development under the Proposed Action (within footprint of existing recreation not included) .................................................................................................................. 5 Table 2-Planned Campsites and Parking Spaces under the Proposed Action ................................ 5 Table 3-Characteristics of the Four Reservoirs in the Project Area ............................................. 16 Table 4-Potential Conservation Areas and Potential Rankings .................................................... 25 Table 5-Species Reported to be Present in the Project Area ........................................................ 29 Table 6-Federal Listed Wildlife Species with Habitat or the Potential to Occur in Larimer County, Colorado .......................................................................................................................... 30 Table 7-CPW State Special Status Mammal Species with Potential to Occur in Project Area .... 31 Table 8- CPW State Special Status Bird Species with Potential to Occur in Project Area .......... 32 Table 9-CPW State Special Status Amphibian and Reptile Species in Project Area ................... 33 Table 10- CPW State Special Status Fish Species with Potential to Occur in Project Area ........ 33 Table 11-CPW State Special Status Fish Species ......................................................................... 34 Table 12- Estimated Visitation by Day and Annual Passes .......................................................... 37 Table 13- Inventory of Existing Facilities .................................................................................... 38 Table 14-Annual Permits Sold by Location.................................................................................. 39 Table 15-Aquatic Nuisance Species Boating Inspections ............................................................ 39 Table 16-Reservable Camping Sites by Reservoir ....................................................................... 40 Table 17-Summary of Existing Land, Water, and Developed Acreage at Each Reservoir (acres) ....................................................................................................................................................... 48 Table 18-Comparison of Alternatives: Developed Lands (land acres only) ................................. 50 Table 19-Historical and Forecast Population ................................................................................ 55 Table 20- Summary of Resource Impacts ..................................................................................... 61 List of Figures Figure 1- Project Area ..................................................................................................................... 2 Figure 2-Horsetooth Reservoir Existing Conditions..................................................................... 12 Figure 3-Carter Lake Existing Conditions .................................................................................... 13 Figure 4-Pinewood Reservoir Existing Conditions ...................................................................... 14 Figure 5-Flatiron Reservoir Existing Conditions .......................................................................... 15 Figure 6-Desired Activities at the Reservoirs ............................................................................... 42 Figure 7-How Visitors Respond to Crowding at the Reservoirs .................................................. 43 Figure 8-Strategies to Improve Recreational Experience ............................................................. 44 Appendices APPENDIX A—RESOURCE MANAGEMENT PLAN FOR HORSETOOTH RESERVOIR, CARTER LAKE, PINEWOOD RESERVOIR, AND FLATIRON RESERVOIR APPENDIX B—ENVIRONMENTAL COMMITTMENTS APPENDIX C— SUMMARY OF COMMENTS ON DRAFT RMP AND ASSOCIATED ENVIRONMENTAL ANALYSIS iv ACRONYMS ADA Americans with Disabilities Act ANS Aquatic Nuisance Species APE Area of Potential Effects ARPA Archaeological Resources Protection Act C-BT Colorado Big-Thompson CNAP Colorado Natural Areas Program CNHP Colorado Natural Heritage Program CPW Colorado Division of Parks and Wildlife CR County Road CSFS Colorado State Forest Service EA Environmental Assessment ECAO Eastern Colorado Area Office EO Executive Order FONSI Finding of No Significant Impact GI Globally Impaired IPAC Information for Planning and Conservation ITA Indian Trust Asset Larimer County Larimer County Department of Natural Resources MBTA Migratory Bird Treaty Act MOU Memorandum of Understanding NEPA National Environmental Policy Act NHPA National Historic Presevation Act NISP Northern Integrated Supply Project Northern Water Northern Colorado Water Conservancy District PFYC Potential Fossil Yield Classification PRPA Paleological Resource Preservation Act Reclamation Bureau of Reclamation RMP Resource Management Plan Sail Club Carter Lake Sailing Club SCORP Statewide Comprehensive Outdoor Recreation Plan SHPO State Historic