Green River Block Water Exchange Contract Final Environmental Assessment PRO-EA-16-020 Upper Colorado Region Provo Area Office Provo, Utah U.S. Department of the Interior Bureau of Reclamation Provo Area Office Provo, Utah January 2019 Mission Statements The Department of the Interior conserves and manages the Nation’s natural resources and cultural heritage for the benefit and enjoyment of the American people, provides scientific and other information about natural resources and natural hazards to address societal challenges and create opportunities for the American people, and honors the Nation’s trust responsibilities or special commitments to American Indians, Alaska Natives, and affiliated island communities to help them prosper. 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. Green River Block Water Exchange Contract Final Environmental Assessment Upper Colorado Region Provo Area Office Provo, Utah Interdisciplinary Team Leader: Jared Baxter 302 East 1860 South Provo, Utah 84606 [email protected] U.S. Department of the Interior Bureau of Reclamation Provo Area Office Provo, Utah January 2019 Contents Page Executive Summary .............................................................................................. 1 Chapter 1 Introduction......................................................................................... 3 1.1 How to Read this Document ....................................................................... 4 1.2 Abbreviations .............................................................................................. 4 1.3 Background ................................................................................................. 5 1.4 Purpose of and Need for Proposed Action .................................................. 8 1.5 Scoping, Public Involvement, and Consultation ......................................... 8 1.5.1 U.S. Fish and Wildlife Service .......................................................... 8 1.5.2 Native American Coordination .......................................................... 9 1.5.3 Public Meeting and Comment Period .............................................. 10 1.5.4 Utah and Colorado State Historic Preservation Offices .................. 10 1.6 Permits and Authorizations ....................................................................... 10 1.7 Related Projects and Documents .............................................................. 10 1.7.1 Lake Powell Pipeline ....................................................................... 10 1.7.2 Operation of FG Dam FEIS (2005) and ROD (2006)...................... 11 1.7.3 Larval Trigger Study Plan (2012; LTSP)......................................... 11 1.8 Scope of Analysis ..................................................................................... 11 Chapter 2 Alternatives ....................................................................................... 12 2.1 Introduction ............................................................................................... 12 2.2 No Action .................................................................................................. 12 2.3 Proposed Action ........................................................................................ 12 Chapter 3 Affected Environment and Environmental Consequences ........... 14 3.1 Introduction ............................................................................................... 14 3.2 Resources Considered and Eliminated from Further Analysis ................. 14 3.3 Affected Environment and Environmental Consequences ....................... 15 3.3.1 Hydrology ........................................................................................ 15 3.3.1.1 Overview ................................................................................. 15 3.3.1.2 Methodology ........................................................................... 16 3.3.1.2.1 Future Depletion Scenarios ............................................ 17 3.3.1.2.2 Future Inflow Hydrology Scenarios............................... 17 3.3.1.3 No Action ................................................................................ 18 3.3.1.4 Proposed Action ...................................................................... 19 3.3.1.5 Cumulative Effects.................................................................. 21 3.3.2 Recreation ........................................................................................ 23 3.3.2.1 No Action ................................................................................ 26 3.3.2.2 Proposed Action ...................................................................... 26 3.3.2.3 Cumulative Effects.................................................................. 27 3.3.3 Wetlands, Riparian, Noxious Weeds, and Vegetation ..................... 27 3.3.3.1 No Action ................................................................................ 29 3.3.3.2 Proposed Action ...................................................................... 29 3.3.3.3 Cumulative Effects.................................................................. 29 3.3.4 Fish and Wildlife Resources ............................................................ 31 3.3.4.1 Fish Species ............................................................................ 31 3.3.4.1.1 No Action ....................................................................... 33 3.3.4.1.2 Proposed Action ............................................................. 33 3.3.4.1.3 Cumulative Effects ......................................................... 33 3.3.4.2 Terrestrial Species ................................................................... 34 3.3.4.2.1 No Action ....................................................................... 34 3.3.4.2.2 Proposed Action ............................................................. 35 3.3.4.2.3 Cumulative Effects ......................................................... 35 3.3.4.3 Avian Species.......................................................................... 35 3.3.4.3.1 No Action ....................................................................... 37 3.3.4.3.2 Proposed Action ............................................................. 37 3.3.4.3.3 Cumulative Effects ......................................................... 37 3.3.5 Threatened and Endangered Species ............................................... 38 3.3.5.1 Mammals................................................................................. 39 3.3.5.2 Birds ........................................................................................ 40 3.3.5.3 Fish .......................................................................................... 42 3.3.5.3.1 No Action ....................................................................... 46 3.3.5.3.2 Proposed Action ............................................................. 47 3.3.5.3.3 Cumulative Effects ......................................................... 47 3.3.5.4 Plants ....................................................................................... 48 3.3.6 Sensitive Species .............................................................................. 51 3.3.6.1 Fish .......................................................................................... 51 3.3.6.1.1 No Action ....................................................................... 52 3.3.6.1.2 Proposed Action ............................................................. 52 3.3.6.1.3 Cumulative Effects ......................................................... 53 3.3.7 Socioeconomics ............................................................................... 53 3.3.7.1 No Action ................................................................................ 53 3.3.7.2 Proposed Action ...................................................................... 53 3.3.7.3 Cumulative Effects.................................................................. 54 3.3.8 Water Rights .................................................................................... 54 3.3.8.1 No Action ................................................................................ 55 3.3.8.2 Proposed Action ...................................................................... 55 3.3.8.3 Cumulative Effects.................................................................. 56 3.3.9 Cultural Resources ........................................................................... 56 3.3.9.1 No Action ................................................................................ 58 3.3.9.2 Proposed Action ...................................................................... 58 3.3.9.3 Cumulative Effects.................................................................. 59 3.3.10 Paleontology .................................................................................. 60 3.3.10.1 No Action .............................................................................. 60 3.3.10.2 Proposed Action .................................................................... 60 3.3.10.3 Cumulative Effects................................................................ 60 3.3.11 Floodplains ..................................................................................... 60 3.3.11.1 No Action .............................................................................