Swan Lake Expansion Project (FERC Project No. 2911) Botany Resource Report FINAL Prepared for: Ketchikan-Misty Fiords Ranger District Tongass National Forest and Ketchikan, Alaska Prepared by: Kathryn Beck, Botanist Beck Botanical Services Karen Brimacombe, Ecologist McMillen, LLC January 2014 Botany Resource Report FINAL TABLE OF CONTENTS 1 Introduction .............................................................................................................................. 1 1.1 Project Description ........................................................................................................... 1 1.2 Regulatory Framework ..................................................................................................... 3 1.2.1 The National Forest Management Act of 1976 (NFMA) .................................... 3 1.2.2 USDA Departmental Regulations 9500-004 ....................................................... 3 1.2.3 36 Code of Federal Regulations (CFR) 219.19 (2000) ....................................... 3 1.2.4 Tongass Land and Resource Management Plan .................................................. 3 1.3 Analysis Area ................................................................................................................... 4 2 Action Alternatives and Reasonably Foreseeable Projects ...................................................... 4 2.1.1 No Action Alternative ......................................................................................... 5 2.1.2 Proposed Action Alternative ............................................................................... 5 2.2 Reasonably Foreseeable Projects...................................................................................... 9 3 Methodology ............................................................................................................................ 9 3.1 Pre-Field Review of Existing Information ....................................................................... 9 3.2 Field Surveys .................................................................................................................... 9 3.3 Determination of Effects and Risk Assessment ............................................................. 10 3.4 GIS Analyses .................................................................................................................. 11 4 Affected Environment ............................................................................................................ 11 4.1 Vegetation Resources ..................................................................................................... 11 4.2 Sensitive Plants ............................................................................................................... 12 4.3 Rare Plants ...................................................................................................................... 13 4.4 General Vegetation Types .............................................................................................. 16 4.5 Invasive Plants ................................................................................................................ 18 5 Environmental Consequences ................................................................................................ 18 5.1 Direct, Indirect, and Cumulative Effects for Sensitive Plants ........................................ 18 5.1.1 Spatulate Moonwort (Botrychium spathulatum W.H.Wagner)......................... 18 5.1.2 Mountain Lady’s Slipper (Cypripedium montanum Douglas ex Lindl.) .......... 19 5.1.3 Large Yellow Lady’s Slipper Orchid (Cypripedium parviflorum Salisb. var. pubescens (Willdenow) O. W. Knight) ............................................................. 20 5.1.4 Alaska Rein Orchid (Piperia unalascensis (Spreng.) Rydb.) ............................ 20 5.1.5 Lesser Round-Leaved Orchid (Platanthera orbiculata (Pursh)) ........................ 22 5.2 Direct, Indirect, and Cumulative Effects for Rare Plants ............................................... 23 5.2.1 Northern Bugleweed (Lycopus uniflorus Michx.) ............................................ 23 5.2.2 Pacific Buttercup (Ranunculus pacificus (Hulten) L.D.Benson) ...................... 25 5.2.3 Wallace’s Spikemoss (Selaginella wallacei Heiron.) ........................................ 26 5.2.4 Bog St. John’s-wort (Hypericum anagalloides Cham. & Schltdl.) ................... 26 5.3 Mitigation ....................................................................................................................... 27 5.4 Direct, Indirect, and Cumulative Effects for General Vegetation .................................. 28 5.4.1 Old-Growth Forest ............................................................................................ 29 5.4.2 Young-Growth Forest ....................................................................................... 30 5.4.3 Unproductive Forest .......................................................................................... 30 5.5 Mitigation Measures for General Vegetation ................................................................. 31 6 References .............................................................................................................................. 31 Page | i Botany Resource Report FINAL LIST OF TABLES Table 1. Summary of Characteristics for the Proposed Action ................................................... 6 Table 2. Known or Suspected Sensitive Plants in the Ketchikan-Misty Fiords Ranger District and Presence of Potential Habitat within the Survey Area ............................ 12 Table 3. Rare Plants Observed within the Survey Area ............................................................ 14 Table 4. General Vegetation Types in the Survey Area............................................................ 16 Table 5. Acres of Impacts to General Vegetation Types due to the Proposed Action .............. 28 LIST OF FIGURES Figure 1. Project Area .................................................................................................................. 2 Figure 2. Project Area Above Dam .............................................................................................. 7 Figure 3. Project Area Below the Dam ........................................................................................ 8 Figure 4. Rare Plants Observed within the Survey Area ............................................................ 15 Figure 5. Vegetation Communities in the Survey Area ............................................................. 17 LIST OF APPENDICES Appendix A Forest Service Alaska Region Sensitive Species List, May 2012 Appendix B Alaska Natural Heritage Program 2012 Rare Vascular Plant List Appendix C Current and Reasonably Foreseeable Projects on the Tongass National Forest Appendix D Survey Types Appendix E Description of Populations of Rare Plant Observed in the Survey Area Appendix F Rare Plant Element Occurrence Field Forms Appendix G Response to Agency Comments on the Draft Resource Report Page | ii Botany Resource Report FINAL 1 Introduction 1.1 Project Description The Southeast Alaska Power Agency (SEAPA) is the licensee for the Swan Lake Hydroelectric Project, Federal Energy Regulatory Commission (FERC) No. 2911 (Project), on the northeast side of Carroll Inlet in Southeast Alaska. SEAPA is currently evaluating the engineering feasibility and value of increasing the storage capacity of the Swan Lake reservoir through an increase in the dam height. Around the reservoir, the FERC boundary roughly follows the 350- foot elevation contour on the Project drawings. SEAPA is planning a 15-foot raise in full pool elevation; dam crest elevation would increase from an elevation of 344 feet to 350 feet to accommodate a new Probable Maximum Flood (PMF) of 347 feet. The normal maximum surface area of the reservoir would increase from 330 feet to 345 feet. As a result of the proposed action, the maximum operating pool of the reservoir would change from 330 feet mean sea level (MSL) to 345 feet MSL, thereby increasing the active storage capacity of Swan Lake from 81,704 acre-feet (ac-ft) to 102,467 ac-ft (an increase of approximately 25 percent). It is estimated that there are about 14 miles of shoreline around the reservoir, much of which is moderately to extremely steep (Figure 1). The Project is located in Sections 11, 12, 13, 14, 15, 20, 21, 22, 23, and 27, Township 72 South, Range 92 East, Copper River Meridian. A portion of the proposed reservoir expansion area will include National Forest System (NFS) lands, particularly in the area of Lost Creek, a tributary that enters the existing reservoir on the northeast side. The Project’s FERC license sets the Project’s boundary around the reservoir at the 350-foot elevation contour. As currently proposed, the increased reservoir will be entirely contained within the existing FERC boundary and there are no plans to seek a change in the boundary with FERC; however, it is possible that in the course of determining necessary mitigation measures a revision of this boundary may be necessary to implement measures sought by the FERC or agencies. These could include measures for recreation, shoreline control, or protection of environmental resources. Any proposed changes to the facilities, the operation of the reservoir, and potential changes to the Project boundary will require amending the Project’s FERC license, a process that includes evaluating the potential impacts