Eklutna Hydroelectric Project 1991 Fish & Wildlife Agreement Implementation Initial Information Package FINAL September 2020 This page intentionally left blank. Eklutna Hydroelectric Project 1991 Fish & Wildlife Agreement Implementation FINAL Initial Information Package Table of Contents Terms, Acronyms, and Abbreviations ..................................................................................................... ix 1.0 Introduction........................................................................................................................................ 1 1.1 Background on 1991 Fish & Wildlife Agreement ..................................................................... 1 1.1.1 Early Hydropower Development and Anchorage’s Energy Needs ..................................... 1 1.1.2 Federal Hydropower Development ..................................................................................... 2 1.1.3 Sale of the Federal Project to the Local Utilities ................................................................. 4 1.2 Requirements of the 1991 Fish & Wildlife Agreement ............................................................. 5 1.2.1 Procedural Requirements ................................................................................................... 5 1.2.2 Schedule Requirements ...................................................................................................... 7 1.3 Early Consultation and Information Gathering ......................................................................... 8 1.3.1 Initial Consultation Meetings ............................................................................................... 9 1.3.2 Technical Group Follow-up Meeting ................................................................................... 9 1.3.3 Site Reconnaissance ........................................................................................................ 10 1.4 Purpose of the Initial Information Package (IIP) .................................................................... 10 1.5 References ............................................................................................................................. 10 2.0 Schedule and Communication Protocols ..................................................................................... 12 2.1 Process Plan and Schedule ................................................................................................... 12 2.2 Communications and Distribution Protocols .......................................................................... 15 2.3 References ............................................................................................................................. 15 3.0 History of Development in the Eklutna Basin and Project Tailrace Area .................................. 16 3.1 Alaska Native Historical and Current Presence ..................................................................... 16 3.2 Alaska Railroad ...................................................................................................................... 21 3.3 Glenn Highway ....................................................................................................................... 22 3.4 Early Hydropower Development ............................................................................................ 25 3.4.1 Planning ............................................................................................................................ 25 3.4.2 Original Construction and Subsequent Improvements ..................................................... 25 3.4.3 Old Project Sold to the City of Anchorage ........................................................................ 28 3.5 Federal Hydropower Development ........................................................................................ 29 3.5.1 Planning and Authorization ............................................................................................... 29 3.5.2 Initial Federal Project Construction ................................................................................... 31 3.5.3 1964 Earthquake and New Dam Construction ................................................................. 33 3.6 Stream Diversions .................................................................................................................. 35 3.7 Military Use and Facilities ...................................................................................................... 36 McMillen Jacobs Associates i September 2020 Eklutna Hydroelectric Project 1991 Fish & Wildlife Agreement Implementation FINAL Initial Information Package 3.8 Campgrounds and Picnic Areas ............................................................................................ 36 3.9 Chugach State Park ............................................................................................................... 37 3.10 Eklutna Water Project ............................................................................................................ 37 3.11 Gravel Pits ............................................................................................................................. 40 3.12 Eklutna Salmon Hatchery ...................................................................................................... 42 3.13 Eklutna Tailrace Day-Use Fishing Access Site...................................................................... 42 3.14 Eklutna River Canyon Illegal Dump Site ................................................................................ 43 3.15 Removal of the Old Diversion Dam ....................................................................................... 44 3.16 Timeline.................................................................................................................................. 49 3.17 References ............................................................................................................................. 51 4.0 Project Facilities and Operations .................................................................................................. 55 4.1 Project Facilities ..................................................................................................................... 55 4.1.1 Dam and Spillway ............................................................................................................. 55 4.1.2 Reservoir ........................................................................................................................... 58 4.1.3 Intake ................................................................................................................................ 58 4.1.4 Tunnel and Surge Tank .................................................................................................... 58 4.1.5 Penstock ........................................................................................................................... 59 4.1.6 Power Plant and Switchyard ............................................................................................. 59 4.1.7 Tailrace ............................................................................................................................. 60 4.2 Project Operations ................................................................................................................. 60 4.2.1 Reservoir Operations ........................................................................................................ 60 4.2.2 Water Usage, Energy Generation, and Cost of Power ..................................................... 63 4.2.3 Flood Protection ................................................................................................................ 63 4.2.4 Spill Events ....................................................................................................................... 64 4.2.5 Emergency Action Plan ..................................................................................................... 66 4.3 References ............................................................................................................................. 66 5.0 Description of Existing Environment ............................................................................................ 67 5.1 Climate ................................................................................................................................... 67 5.1.1 Historical Climate .............................................................................................................. 67 5.1.2 Climate Change ................................................................................................................ 67 5.1.3 References ........................................................................................................................ 69 5.2 Geology .................................................................................................................................. 70 5.2.1 Glacial Influence ................................................................................................................ 70 5.2.2 Eklutna Lake ..................................................................................................................... 71 5.2.3 Dam Site ........................................................................................................................... 71 5.2.4 Eklutna River Valley and Canyon ....................................................................................