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Swan Lake Expansion Project (FERC Project No. 2911) Wetlands Resource Report REVISED FINAL Prepared for: Ketchikan-Misty Fiords Ranger District Tongass National Forest

and

Ketchikan, Alaska Prepared by: Karen Brimacombe, Ecologist

McMillen, LLC

March 2014

Wetlands Resource Report REVISED FINAL

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TABLE OF CONTENTS 1 Introduction ................................................................................................................................ 1

1.1 Project Description ........................................................................................................... 1 1.2 Regulatory Framework ..................................................................................................... 3

1.2.1 Tongass Land and Resource Management Plan ................................................ 3 1.2.2 Clean Water Act ................................................................................................ 4 1.2.3 Section 10 of the Rivers and Harbors Act ......................................................... 4

1.3 Analysis Area ................................................................................................................... 5 2 Action Alternatives and Reasonably Foreseeable Projects ........................................................ 5

2.1 No Action Alternative ...................................................................................................... 5 2.2 Proposed Action Alternative ............................................................................................ 5

2.2.1 Dam, Spillway, and Intake ................................................................................ 9 2.2.2 Reservoir ........................................................................................................... 9 2.2.3 Additional Facilities and Modifications .......................................................... 10

2.3 Reasonably Foreseeable Projects.................................................................................... 10 3 Methodology ............................................................................................................................ 10

3.1 Pre-Field Review of Existing Information ..................................................................... 10 3.2 Field Surveys .................................................................................................................. 10

4 Affected Environment .............................................................................................................. 11 4.1 Wetland Resources ......................................................................................................... 11

4.1.1 Forested Wetlands ........................................................................................... 12 4.1.2 Emergent Sedge Wetlands ............................................................................... 12 4.1.3 Moss Muskegs ................................................................................................. 13

5 Environmental Consequences .................................................................................................. 13 5.1 Effects from Rising Reservoir Levels ............................................................................ 14

5.1.1 Direct and Indirect Effects............................................................................... 14 5.2 Effects from Construction Activities .............................................................................. 14

5.2.1 Direct and Indirect Effects............................................................................... 14 5.3 Cumulative Effects ......................................................................................................... 14 5.4 Mitigation ....................................................................................................................... 15 5.5 Unavoidable Adverse Impacts ........................................................................................ 15 5.6 Irreversible and Irretrievable Commitments of Resources ............................................. 15

6 References ................................................................................................................................ 15

LIST OF TABLES Table 1. Summary of Characteristics for the Proposed Action ................................................... 9 Table 2. Acres of Wetland Resources in the Survey Area1/ ...................................................... 12 LIST OF FIGURES Figure 1. Project Area .................................................................................................................. 2 Figure 2. Project Area Above Dam .............................................................................................. 6 Figure 3. Project Area Below the Dam ........................................................................................ 7 Figure 4. Wetland Resources within the Project Area ................................................................. 8 LIST OF APPENDICES Appendix A Known Projects in the Vicinity of the Swan Lake Expansion Project Appendix B Response to Agency Comments on the Draft Wetlands Report


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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 to 102,467 acre-feet (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 North, Range 92 East, Copper River Meridian. A portion of the proposed reservoir expansion area will include National Forest System (NFS) landsin 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 measues sought by the FERC or agencies. These could include measure 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 to environmental resources from the proposed action.

For the Initial Consultation Document (ICD) submitted in April 2013, the FERC Boundary above the reservoir, defined as the 350-foot contour on the revised Exhibit K maps dated March 29, 1985, was used and rectified to the extent possible. Since the completion of the ICD and associated study reports, vessel-mounted light detection and ranging (LiDAR) was conducted to better assess the actual location of the 350-foot contour around the entirety of the lake. Based on the results of this work, a more refined 350-foot boundary and 330-foot full pool contour was developed for use in better defining potential project level impacts (Tetra Tech 2014).

This Swan Lake Expansion Project Wetlands Resource Report provides an assessment of the current condition of wetland resources in the survey area and the potential effects of implementing the proposed alternatives on these resources. Two alternatives are evaluated in this report: No Action, as required under the National Environmental Policy Act (NEPA), and the proposed action. This analysis addresses the potential effects associated with construction and operation of the proposed project. The following analysis uses existing information from spatial GIS data, field survey results, scientific literature, and other sources, as appropriate.


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Figure 1. Project Area


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The final appendix to this report provides a response to general and resource-specific USDA Forest Service comments on the final Resource Report. This Revised Final Resource Report incorporates the comments as appropriate. Where changes were not made, they are noted and will be addressed in greater detail in the Environment Assessment for the expansion project as needed.

1.2 Regulatory Framework Management activities on NFS lands are required to comply with the Tongass Land and Resource Management Plan (Forest Plan) and federal and state laws. Relevant standards and regulations intended to protect botanical resources are summarized in the subsections below.

1.2.1 Tongass Land and Resource Management Plan The Forest Plan is the governing document for management activities that take place within the Tongass National Forest (USDA Forest Service 2008). It consists of three parts that work together to facilitate the development of management activities. These parts include: forest goals and desired conditions for resources; the management prescriptions for each of the 19 land use designations (LUDs); and the Forest-wide Standards and Guidelines, which apply to all or most areas of the Forest and provide for the protection and management of forest resources.

LUD-specific Standards and Guidelines apply in the LUDs where land-disturbing activities would occur (USDA Forest Service 2008, Chapter 3). In addition, there are Forest-wide Standards and Guidelines for wetlands that apply and provide for resource protection across the Forest (USDA Forest Service 2008, Chapter 4). Forest-wide standards and guidelines for wetlands include the following (USDA Forest Service 2008, p. 4-88):

Wetlands: WET

III. Land Use Activities

A. The discharge of dredged or fill material onto wetlands is regulated under Section 404 of the Clean Water Act, which is administered by the U.S. Army Corps of Engineers (USACE) and U.S. Environmental Protection Agency (EPA). Certain categories of activities are exempt from regulation, while others may be permitted (refer to 33 Code of Federal Regulations [CFR] 323.4 Part 330 Appendix A 325). Consult with USACE early in the planning process to determine whether a 404 permit is required. For non-exempt activities, permit requirements may include compensation or replacement of any lost aquatic function.

B. Consistent with the Clean Water Act, as amended, use Best Management Practices (BMPs) in all management activities that could affect water quality of wetlands. BMPs are intended to ensure that flow and circulation patterns, as well as chemical and biological characteristics of water are not impaired. (Forest Service Handbook [FSH] 2509.22, BMP 12.5)

C. Before issuing authorizations, leases, easements, rights-of-way, or exchanging lands containing wetlands, identify uses that are restricted under identified Federal, state, or local wetlands regulations. Incorporate appropriate restrictions, where necessary, to protect or minimize wetland impacts, or withhold such properties from exchange.

D. Cooperate with state and Federal agencies having overlapping resource management responsibilities for wetlands, including the Alaska Department of Fish and Game, Alaska Department of Environmental Conservation, Alaska Department of Natural Resources, USACE, EPA, National Marine Fisheries Service, and the U.S. Fish and Wildlife Service.


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E. Mitigate to minimize impacts caused by activities when BMPs do not perform as expected.

F. When decommissioning roads through wetlands, restore natural drainage patterns.

G. Timber harvest may occur on forested wetlands that meet suitable criteria and are in development LUDs.

1.2.2 Clean Water Act Discharges of dredged or fill material into wetlands are regulated through Section 404 of the Clean Water Act (CWA) by USACE and the EPA. USACE and EPA regulate wetlands on private, state, and federal land.

Under Section 404, USACE issues a number of nationwide permits for different types of activities that result in minimal individual and cumulative adverse effects on the aquatic environment. Permanent wetland losses greater than 0.5 acre or stream impacts greater than 300 linear feet require an individual permit.

1.2.3 Section 10 of the Rivers and Harbors Act Section 10 of the Rivers and Harbors Act of 1899 prohibits the unauthorized obstruction or alteration of any navigable water of the United States.

Obstruction or alteration includes: construction of any structure in or over any navigable water of the United States, excavation of dredge, or deposition of, fill material, any other activities affecting the course, location, condition, or capacity of such waters.

Consultation with U.S. Army Corps of Engineers On May 22, 2013, SEAPA met with stakeholders, including USACE, to discuss permitting requirements for the Swan Lake Expansion Project. USACE indicated that it is their responsibility to administer Section 10 of the Rivers and Harbors Act and Section 404 of the CWA and regulate discharge of fill material into waters of the United States, including wetlands. During consultation, USACE indicated that if there was no placement of fill into waters regulated under Section 10 or Section 404 than a permit would not likely be required. USACE also indicated that their area of concern with respect to the expansion project was whether there would be placement of fill into wetlands or other waters below the dam. SEAPA indicated that wetland resources would be inundated by rising reservoir levels, but project construction would not require fill, removal, or discharge of material into wetlands or other waters of the United States.

During this consultation, SEAPA also indicated that wetlands within the survey area were not formally delineated, but that wetland resources within the survey area, including the areas below the dam, were mapped and characterized. USACE indicated that without a formal delineation below the dam, there is some concern that wetlands may be directly impacted by project construction. USACE’s initial conclusion was that permits would likely not be required, but without final plans and delineation of wetlands within construction areas, a firm determination could not be made. Final plans, supporting design report (when complete), and additional information regarding wetland resources in the expansion project area may be used by USACE as a “pre-application” to advise SEAPA whether permits will be required. A “no permit required” letter would be issued if appropriate. This letter, if deemed appropriate, would specifically include reference to the 26 acres of wetlands on NFS lands in the expansion project area.


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1.3 Analysis Area The area analyzed for direct and indirect effects to wetland resources includes the area within the FERC boundary (i.e., survey area) (Figure 1). The survey area for wetland resources includes the area between the current spillway crest elevation (330 feet) and the proposed new dam crest elevation of 350 feet (3 feet of freeboard above the PMF of 347 feet). It is estimated that there are about 14 miles of the Swan Lake reservoir shoreline at the 350-foot elevation contour; including portions of Lost Creek, Track Creek, Mint Creek, and Fry Creek (Figure 2). Although the survey area includes the area up to 350 feet elevation (current FERC boundary as revised by LiDAR and survey), the area of impacts from the proposed project anticipates that the normal maximum surface area of the reservoir would increase from 330 feet to 345 feet. Vessel-mounted sidescan LiDAR was conducted in November 2013 for the area above the dam and this report includes revisions to the ICD and associated study reports. Revisions based on LiDAR did not change any key findings of this report; however, it serves to provide a more refined analysis of potential project impacts above the dam.

The survey area also includes a 150-foot buffer around areas where temporary and permanent construction activities (e.g., area around existing dam, existing and proposed staging areas, docks, work garage, existing roads, powerhouse) associated with the proposed project would likely occur. This area is located below the dam and near existing facilities (Figure 3).

The areas described above were selected as the survey area because all project-related disturbance is expected to occur within this area. The area analyzed for cumulative effects to wetland resources includes the survey area described above as well as the entire Value Comparison Unit (VCU) 7450 in which the Swan Lake Expansion Project is located (Figure 4).

2 Action Alternatives and Reasonably Foreseeable Projects

Two alternatives are evaluated in this report: No Action, as required under the National Environmental Policy Act (NEPA), and the proposed action. The analysis addresses the potential effects to wetlands associated with construction and operation of the proposed project. The following analysis uses existing information from spatial GIS data, field survey results, scientific literature, and other sources, as appropriate.

2.1 No Action Alternative The No Action Alternative would be to not modify the existing dam and to continue operating the reservoir as it is currently managed. There would be no inundations of the lake perimeter compared with today’s environment, but system spill would continue and therefore the opportunity to displace on-going diesel generation would be lost. In addition to providing an option for the decision-maker, the No Action Alternative is analyzed to provide a baseline for evaluation of the effects associated with the proposed action.

2.2 Proposed Action Alternative The existing Swan Lake Dam consists of a 174-foot-high concrete arch dam creating an 81,704 ac-ft active storage reservoir. Water passes through a concrete power tower located on the right abutment upstream of the dam, and passes through a 2,300-foot-long power tunnel to the powerhouse. The tunnel feeds an indoor-type powerhouse fitted with two 12,500-kilovolt ampere generating units. Power is transmitted from the powerhouse to Ketchikan, Wrangell, and Petersburg, Alaska.


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Figure 2. Project Area Above Dam


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Figure 3. Project Area Below the Dam


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Figure 4. Wetland Resources within the Project Area


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2.2.1 Dam, Spillway, and Intake The Swan Lake Dam is a double curvature elliptical arch dam with a crest elevation of 344.0 feet, which is 174 feet above the lowest foundation line. A 100-foot-wide un-gated ogee spillway located in the center of the dam. Flow passes over the ogee crest at elevation 330.0 feet and passes over a concrete chute spillway that flips the flow downstream from the dam toe into an excavated plunge pool. The intake consists of a concrete monolith structure located on the right (north) abutment upstream of and separate from the dam. The trashrack sill elevation of the intake entrance is at elevation 232.0 feet

The proposed action would raise the crest of the dam to 350 feet. The hard crest of the spillway would remain at 330 feet MSL. A 5-foot-high Obermeyer gate system would be installed to achieve the new maximum normal operating pool level of 345 feet. The existing spillway gate structure would be extended upstream an additional 5 to 7 feet to accommodate the increased gate length. The intake structure would need to be raised to contain the maximum operating pool of 347.0 feet. This would require raising the concrete intake structure, relocating the gate hoist equipment, increasing the gate lift shaft, and modifying the right abutment. Much of these modifications would be accomplished using a floating barge platform. On the right abutment, a new concrete dam section will have to be extended across the existing access road and tie into the exposed rock abutment. This will require selective removal of the existing access road and fill area to expose undisturbed bedrock.

2.2.2 Reservoir Construction of the Swan Lake Dam raised the level of natural Swan Lake from elevation 236.0 feet to a normal maximum elevation of 330.0 feet. The minimum reservoir surface elevation is now at elevation 271.5 feet, which provides an active storage of 81,704 ac-ft. Using the results of the LiDAR study, the reservoir is approximately 2 miles in length and has a surface area of 1,474 acres when at the full pool level of 330.0 feet.

The proposed action would increase the new normal maximum surface elevation to 345 feet MSL; however, for the purposes of the Resource Report, potential impacts are assessed using the refined (LiDAR-based) 350-foot elevation contour. Based on the slightly more conservative impact assessment up to the 350-foot elevation, the impoundment would inundate an additional 93 acres. The active storage of the Project would increase by approximately 25 percent to 102,467 ac-ft. The PMF elevation would increase to 347 feet. The existing FERC boundary follows the 350-foot contour around the reservoir and would not be modified.

Table 1 presents the key hydrological and reservoir data under existing and proposed conditions.

Table 1. Summary of Characteristics for the Proposed Action

Item Existing Conditions Proposed

Conditions Reservoir Data Surface Area (acres) 1/ 1,474 1,567 Normal Pool El. (MSL) 330.0 345.0 Minimum Operating Pool El. 271.5 271.5 Active Storage (ac-ft) 81,704 102,467 1/ Surface area revised based on LiDAR study results conducted in November 2013 (Tetra Tech 2014). Other Sources: Swan Lake Project Final Reports, Four Dam Pool Agency, Swan Lake Hydroelectric Project, Supporting Technical Information Document, February 2005.


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2.2.3 Additional Facilities and Modifications Additional modifications and facilities necessary to support construction and operation of the expanded dam include:

• Raising existing access road, by filling with granular material, to cross the new dam at an elevation of 350 feet.

• Re-grading of existing access roads in the area.

• Rebuilding the reservoir boat dock which would be submerged by any reservoir raise.

• Raising or modifying the equipment room and hoist to allow them to be submerged during flooding events.

• Use of existing staging areas for construction activities associated with the proposed action.

Figure 3 shows the layout of the area below the dam where construction activities would occur. Proposed temporary staging areas, required for dam modification and assembly of the Obermeyer gates, would be located on flat benches along existing access roads below (west) of the existing dam. These areas would consist primarily of staging and laydown areas from original construction. Materials such as trailers, free-draining rock and gravel, and temporary electrical would be barged in.

2.3 Reasonably Foreseeable Projects Known current and reasonably foreseeable future projects in the vicinity of the Swan Lake Expansion Project are discussed in Appendix A. These projects include timber harvest and road activities on NFS lands, and restoration activities in the VCU just south of the Swan Lake Expansion Project.

3 Methodology 3.1 Pre-Field Review of Existing Information Prior to field surveys, a pre-field review of the survey area was conducted. Data reviewed for wetland resources in the survey area was based on the Tongass National Forest wetland mapping layer. This GIS mapping layer has been modified from the National Wetland Inventory (NWI) maps, through the inclusion of the common wetland types present in Southeast Alaska. Additionally, the Ketchikan Area soil survey for the Tongass National Forest area was reviewed to determine the potential location of hydric soils within the survey area.

3.2 Field Surveys Field surveys for wetland resources were conducted August 6 to 10, 2012. Surveys were conducted within the survey area (i.e., FERC boundary) which included the shoreline of Swan Lake and along the banks of Lost Creek up to the 350-foot elevation level. Surveys were dispersed throughout the survey area in a variety of habitat types, elevations and aspects. The surveys were done primarily by boat because steep terrain and dense vegetation restricted the ability to survey the majority of the shoreline on foot. The shoreline and creek margins were surveyed in the limited areas where slope and vegetation density allowed. Surveys of the survey area focused on the area above the dam an area estimated to be 93 acres in size. However, additional surveys for wetland resources were conducted below the dam and near existing


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facilities in an effort to gather baseline information to address potential impacts from construction activities.

Several wetland types were observed during field surveys. These include forested wetlands, emergent wetlands, and moss muskegs. Wetland resources were mapped, to the extent possible, using a Trimble GeoXH global positioning system unit (GPS). Wetlands that could not be mapped using GPS were hand-delineated on aerial maps using the Tongass National Forest wetland layers and hydric soils layers from the Ketchikan area soil survey for the Tongass National Forest to help refine the boundaries. Formal wetland delineations were not conducted.

4 Affected Environment The accepted definition of a wetland by USACE, EPA, and the Tongass Forest Plan is “those areas that are inundated or saturated by surface water or groundwater with a frequency and duration sufficient to support, and under normal circumstances do support, a prevalence of vegetation typically adapted to life in saturated soil conditions” (33 Code of Federal Regulations [CFR] 328.3 and 40 CFR 230.3). The U.S. Fish and Wildlife Service has developed a hierarchical wetland and deepwater habitat classification system, which classifies wetlands by system (e.g., estuarine, palustrine), substrate, flooding regime, and vegetation type (Cowardin et. al. 1979). The Cowardin vegetation types include forested, scrub shrub, emergent, moss/lichen and aquatic bed. As a result of its cool and wet climate, Alaska has several wetland subtypes that are common and widespread in the state that are not specifically addressed in Cowardin et al. (1979). Therefore, the Tongass National Forest has developed a classification system to characterize these wetlands, which generally follows the Cowardin system while providing additional categories for the wetland types common in Alaska; in particular, wetlands with deep organic soils (DeMeo and Loggy 1989). These wetlands types are described in more detail in the following sections.

The Swan Lake Expansion Project area is located on the Ketchikan-Misty Fiords Ranger District on Revillagigedo Island in southeast Alaska. The Tongass National Forest, including Revillagigedo Island, is dominated by temperate rainforest. The maritime climate is characterized by cool, wet summers and mild winters with significant precipitation as snow and rainfall. In Ketchikan, approximately 23 miles southwest of the study area, typical summer temperatures average 60 to 65°F, while winter temperatures average 39 to 44°F. The year-round average temperature is 51.6°F. Annual precipitation as rainfall averages 117 inches, with the least precipitation (16 percent) occurring from May through July. The wettest month is October with an average of more than 22 inches accumulation. Snowfall accumulation averages 37 inches per year, with the most snow accumulating in January (35 percent) (Western Regional Climate Center 2012). The study area lies about 300 to 350 feet higher in elevation than Ketchikan.

4.1 Wetland Resources Wetland resources in the survey area were mapped using a combination of the Tongass National Forest wetland layers, the hydric soils layers from the Ketchikan area soil survey for the Tongass National Forest, and wetland boundaries delineated during field surveys of the survey area in August 2012 (see Section 3.2). Approximately 5.4 percent or 84.6 acres of the survey area consists of wetlands. Several types of wetland communities, including forested wetlands, emergent wetlands, and moss muskegs are found in the survey area (Table 2; Figure 4). The different wetland types found in the survey area are briefly described below.


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Table 2. Acres of Wetland Resources in the Survey Area1/

Wetland Type Total Wetland Acres

in Survey Area Percent of

Survey Area1/ Acres on NFS

Land Forested Wetlands 68.1 4.3 25.9 Emergent Wetlands 2/ 15.0 1.0 0.0 Moss Muskegs 1.5 0.1 0.0 Total 84.6 5.4 25.9

1/ Survey area includes the area within the existing FERC (350-foot elevation contour above the dam) and the portion within the FERC boundary below the dam, totaling approximately 1,621 acres. This excludes the area of open water associated with the current maximum reservoir level of Swan Lake. 2/ Includes areas mapped as tall sedge fens in the Tongass National Forest wetland mapping layer.

4.1.1 Forested Wetlands Forested wetlands occur on poorly or very poorly drained hydric mineral and organic soils. Forested wetlands are most common on broad glacial valley bottoms, gently sloping hill slopes or benches, but are also commonly found on steep terrain in areas overlaying volcanic geology. These wetlands provide important functions including wildlife habitat, water quality improvement, peak flow reduction and erosion control, organic matter production and export, and nutrient and carbon cycling (Cooke 2005). Forested wetlands may support the transfer of water to downslope resources, function as recharge areas for groundwater and streams, and provide depositional areas for sediment and nutrients.

Forested wetlands are wetlands dominated by vegetation greater than 20 feet in height. The overstory in forested wetlands in the survey area is varied but typically consists of western hemlock (Tsuga heterophylla), western red cedar (Thuja plicata), Alaska yellow cedar (Callitropsis [Chamaecyparis] nootkatensis), and red alder (Alnus rubra). The understory is often dominated by skunk cabbage (Lysichitum americanum). Other shrub and herbaceous species occurring in the understory of forested wetlands in the survey area include seep monkeyflower (Mimulus guttatus), deer cabbage (Nephrophyllidium crista-galli), fowl mannagrass (Glyceria elata [G. striata]), California black currant (Ribes bracteosum), and salmonberry (Rubus spectabilis). In the survey area, approximately 68.1 acres consists of forested wetlands. Approximately 26 acres of forested wetlands occur on NFS lands.

4.1.2 Emergent Sedge Wetlands Emergent wetlands contain organic soils that are very poorly drained, moderately deep, and are dominated by sedges and grasses. They may include poor fens and rich bogs and there is typically some water flow through. Vegetation in these wetlands typically consist primarily of various sedges and mosses with scattered shrubs. In the survey area, emergent wetlands were typically found along the margin of Swan Lake. Three small emergent wetlands were observed in the portion of the survey area below the dam along existing roads and near existing facilities associated with dam operations (Figure 4).

Species commonly observed in emergent wetlands along the margins of Swan Lake include Sitka sedge (Carex aquatilis), smoothstem sedge (Carex laeviculmis), bluejoint reedgrass (Calamagrostis canadensis), marsh cinquefoil (Comarum palustre [Potentilla palustris]), western water hemlock (Cicuta douglasii), scattered willows (Salix sp.), and occasionally small-fruited bulrush (Scirpus microcarpus). These wetlands provide habitat for unique plants and animals, and contribute water to downslope resources, provide carbon and nutrient cycling benefits for watershed function, and provide water storage for flood and erosion control (EPA 2011). Common species found in the emergent wetlands below the dam along existing roads and near existing facilities include seep monkeyflower (Mimulus guttatus), reed canarygrass (Phalaris


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arundinacea), common horsetail (Equisetum arvense), toad rush (Juncus bufonius), lakeshore sedge (Carex lenticularis),and silverweed cinquefoil (Argentina anserina).

In the survey area, approximately 15.0 acres consists of emergent wetlands with nearly all acres located adjacent to Swan Lake. Three small wetlands comprising 0.26 acre total (0.05, 0.08, and 0.13 acre) were mapped below the dam and near existing facilities (Figure 4). Emergent wetlands mapped in the survey area include types mapped as freshwater emergent sedge (emergent sedge/FW) and tall sedge fens. No emergent wetlands are documented on NFS lands.

4.1.3 Moss Muskegs Moss muskegs are characterized by nutrient limiting acid peat bogs, dominated by sphagnum moss and peat deposits. Muskeg wetlands support a distinctive flora which are adapted to life in these acidic, wet, low-nutrient environments (EPA 2011). Soils in moss muskegs are typically organic peat deposits that accumulate over unconsolidated glacial till or impermeable glacial silts, typically on gentle or nearly level slopes. Moss muskegs often have no significant inflow or outflow of water other than precipitation, thus ponded areas, a result of a high water table, occur within the wetland. These wetlands function as areas of surplus water and peat accumulation creating a stable microclimate and habitat for waterfowl and wildlife, including cranes, black bear, amphibians, mink, and deer. In the survey area, one moss muskeg was observed north of Track Creek on the southwestern shore of Swan Lake (Figure 4). Plants observed in this wetland included small cranberry (Vaccinium oxycoccos), bog blueberry (Vaccinium uliginosum), alpine laurel (Kalmia microphylla ssp. occidentalis), bog Labrador tea (Ledum groenlandicum), cottongrass (Eriophorum spp.), sundews (Drosera spp.), threeleaf goldthread (Coptis trifolia), smoothstem sedge, few-flowered sedge (Carex pauciflora), tufted bulrush (Trichophorum cespitosum), sphagnum moss (Sphagnum spp.) and scattered stunted trees including lodgepole pine (Pinus contorta), red alder and Sitka alder. Approximately 1.5 acres of the survey area consists of muskeg habitat. No muskegs were documented on NFS lands (Table 4).

5 Environmental Consequences The No Action Alternative would have no effect on wetland resources in the survey area because the proposed dam expansion would not be built and there would be no resulting increase in the maximum reservoir pool elevation or impacts due to project construction.

This section describes the direct, indirect, and cumulative effects on wetland resources from the proposed action. Direct and indirect effects to wetland resources are estimated based on the acres of the survey area (FERC boundary) that would be temporarily or permanently impacted by the proposed expansion project.

Direct impacts to wetland resources from the proposed project include acres of wetland affected by construction activities, either as permanent or temporary wetland fill, or as a result of inundation due an increase in maximum full pool reservoir elevation. The majority of activities associated with expansion of the new dam would occur in areas already disturbed or developed for construction of the existing dam; however, wetlands in these areas could potentially be impacted. Direct impacts to wetland resources would primarily occur due to inundation. Indirect impacts include potential changes to hydrology that could result from project construction and inundation.

Cumulative effects are those that result from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions. Cumulative impacts are the sum of the direct and indirect impacts from the Swan Lake Expansion Project plus other projects that


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have occurred in the past, are presently occurring, or are expected to occur in the foreseeable future. Individually these impacts may be minor, but together can result in cumulative impacts over time.

Potential mitigation measures for the expansion project are included in Section 5.3.

5.1 Effects from Rising Reservoir Levels

5.1.1 Direct and Indirect Effects Rising reservoir levels would flood areas of emergent and forested wetlands and moss and forested muskegs within the survey area. These areas of wetland resources would be permanently lost due to inundation. Similar wetland communities may develop adjacent to the new reservoir margins depending on steepness of the adjacent slope. Alternatively, rising reservoir levels could indirectly alter the nature and stability of the adjacent wetland vegetation. Approximately 68.1 acres of forested wetlands, 15.0 acres of emergent wetlands, and 1.5 acres of moss muskegs would be permanently lost due to inundation from rising reservoir levels. This includes approximately 26 acres of forested wetlands on NFS land.

Indirect impacts to wetland resources could also occur from rising and fluctuating water levels in the reservoir in association with dam operation. Changes to hydrology in wetlands adjacent to the new maximum full pool reservoir elevation could impact the functions of these wetlands and alter the species composition of these areas. Alteration of species composition and hydrologic regimes in these wetlands could also result in the loss or modification of wetland habitat. Indirect impacts on wetland habitat through changes in hydrology and soil structure and stability could occur not only from rising reservoir levels but also from fluctuating reservoir levels.

5.2 Effects from Construction Activities

5.2.1 Direct and Indirect Effects

No forested wetlands or moss muskegs would be directly or indirectly impacted by construction activities associated with expansion of the new dam. Although three small wetlands (0.05, 0.08, and 0.13 acre) of emergent wetland were mapped below the existing dam totaling 0.26 acre, facilities such as proposed staging areas have been sited to avoid impacting these wetland resources. Additionally, these emergent wetlands would be flagged prior to construction. None of the emergent wetlands below the dam are located on NFS land. Emergent wetlands adjacent to areas where construction activities would occur are highly degraded and located in heavily disturbed areas (i.e., adjacent to roads, in roadside ditches, and in previously cleared areas).

There is potential for indirect impacts to wetland resources from changes to hydrology associated with construction activities. If hydrology of wetlands adjacent to construction activities is altered, it could result in a change in the species composition and a loss of wetland functions. Indirect effects to emergent wetlands could also result from invasive plant spread. Ground or soil disturbance to or adjacent to wetland resources would increase the risk for invasive plant establishment.

5.3 Cumulative Effects Cumulative effects to wetland resources would occur as a result of past, present, and future projects. Rising reservoir levels due to the proposed action would contribute to approximately


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84.6 acres of cumulative impact to wetland resources within VCU 7450. Reasonably foreseeable projects in the vicinity of the Swan Lake Expansion Project are identified in Appendix A. The only reasonably forseeable projects in the vicinity of the Swan Lake Expansion Project that has the potential to impact wetland resources include road activities on NFS lands. The acres of impacts to wetland resources due to road actitivities (e.g., road grading, drainage structure replacement, decommissioning of unauthorized roads) is unknown at this time. All road maintenance activities; however, would be required to implement Forest Plan standards and guidelines, including Best Management Practices (BMPs) to avoid and reduce impacts to wetland resources.

5.4 Mitigation The effects of the Swan Lake Dam Expansion Project on wetlands would be limited through the site-specific application of Forest Plan Standards and Guidelines as well as BMPs for all action alternatives. Temporary staging areas and road modification activities would avoid wetlands where possible and would be constructed in accordance with the BMPs identified in FSH 2509.22 and other applicable BMPs.

Because of the preponderance of wetlands along the perimeter of Swan Lake, avoidance of impacts to wetlands resulting from the proposed 15-foot increase in pool elevation would not be feasible.

5.5 Unavoidable Adverse Impacts Effects to wetland resources would be avoided or minimized, to the extent possible, during construction and operation with the use of BMPs and application of Forest Plan Standards and Guidelines. Unavoidable adverse impacts from the proposed action include inundation of approximately 84.6 acres of wetlands due to rising reservoir levels.

5.6 Irreversible and Irretrievable Commitments of Resources

The Swan Lake Expansion Project will result in an irreversible loss of approximately 84.6 acres of wetlands. These 84.6 acres of wetlands would be lost due to inundation from rising reservoir levels. This includes inundation of approximately 26 acres of forested wetlands on NFS lands in the Lost Creek area. However, additional wetlands adjacent to the Swan Lake and within the Lost Creek riparian area would likely be created over time.

6 References Cooke (Cooke Scientific Services, Inc.). 2005. Pacific Northwest Forested Wetland Literature

Survey Synthesis Paper. April 2005. 95 pp.

Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Department of the Interior, Fish and Wildlife Service, Washington, D.C. 131pp.

DeMeo, T.E., and W.D. Loggy. 1989. Identification, classification, and delineation of wetlands using soils and vegetation data. Final Report. USDA Forest Service, Tongass National Forest, Ketchikan Area. 59 pp.


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EPA (U.S. Environmental Protection Agency). 2011. Environmental Protection Agency. Wetland Types. Available online at: http://water.epa.gov/type/wetlands/bog.cfm

Swan Lake Project Final Reports. 2005. Part 12-Independent Consultant Inspection Report, Supporting Technical Information Document, and Potential Failure Mode Analysis Report, prepared for the Four Dam Pool Power Agency, February 2005.

Tetra Tech. 2014. Swan Lake Multibeam Bathymetric and Vessel-Mounted LiDAR Survey Technical Memorandum–Survey Results. Prepared for: McMillen, LLC and the Southeast Alaska Power Agency (SEAPA). 69 pp. January.

USDA Forest Service (U.S. Department of Agriculture, Forest Service). 2008. Tongass National Forest: Land and Resource Management Plan. U.S. Dept. of Agriculture, Alaska Region: USDA Forest Service, Tongass Land Management Planning Team, Juneau.

Western Regional Climate Center. 2012. Cooperative Climatological Data Summaries. Available online at: http://www.wrcc.dri.edu/


Appendix A – Known Projects in the Vicinity of the Swan Lake Expansion Project


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Known Projects in the Vicinity of the Swan Lake Expansion Project The following actions are either present or considered reasonably foreseeable, and are combined with past actions considered in the cumulative effects analysis. These actions include Free Use timber harvesting, pre-commercial thinning, road improvement/building, and wildlife/fish habitat restoration. Projects were identified within Value Comparison Unit (VCU) 7450 in which the Swan Lake project is located. The level of cumulative effects that may occur in the future due to these activities will depend on the rate at which new projects are implemented and the rate at which disturbances from past and present activities recover. Furthermore, if and when these projects are implemented is heavily dependent on future levels of available funding.

Timber Harvest on NFS Lands There are is are no timber harvest project proposed or approved on National Forest System (NFS) lands within VCU 7450 (USDA Forest Service 2013a).

Free Use timber harvest is expected to occur within the general area. Free use harvesting can be up to 10 thousand board feet (MBF) per person per year. Individuals must submit a Free Use Permit Application to the Forest Service prior to free use timber harvesting. Selected trees must also be evaluated and approved by the Forest Service prior to their removal. Free use removal is expected to have similar effects as micro-sales, although this type of removal may include more live standing trees.

Timber Harvest on State Lands Per the State of Alaska Department of Natural Resources Division of Forestry (ADNR DOF) draft of the Coastal Region’s Southern Southeast Area Five-Year Schedule of Timber Sales (ADNR DOF 2013), no timber harvest is scheduled for state lands in the vicinity of the Swan Lake project.

Young-Growth Treatments on NFS Lands No young-growth treatments are planned or under contract within VCU 7450 (USDA Forest Service 2013b).

Road Activities on NFS Lands The Ketchikan-Misty Fiord Ranger District Access and Travel Management Plan (ATM) was completed in 2008 (USDA Forest Service 2009). The ATM provides direction and requirements for road storage, decommissioning, motorized trail development, and other roadwork, which will be implemented in the foreseeable future based on the availability of funding. The ATM designates approximately 109 miles of road open to motorized vehicle use and 37 miles of OHV trail.

Ongoing road maintenance will continue to occur in along NFS road systems throughout the Ketchikan-Misty Fiords Ranger District, including the road systems in the vicinity of the Project, as funding becomes available (USDA Forest Service 2013c). These activities could include road grading, drainage structure replacement, decommissioning of unauthorized roads, and other ground-disturbing activities that will cause short-term sediment increases. All road maintenance


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activities would be required to implement Forest Plan standards and guidelines, including Best Management Practices (BMPs) to ensure water quality standards are achieved.

Restoration Activities in the Vicinity of the Swan Lake Expansion Project

The Saddle Lakes Riparian Thinning and Small-scale Stream Rehabilitation project is identified in the Tongass 5-year Fisheries, Watershed, and Soils Program Project Schedule (USDA Forest Service 2013d). This project would include the restoration of approximately 3 miles of stream and associated riparian thinning south of the Swan Lake project area in VCUs 7460, 7470, and 7530. The project will continue to undergo assessment through 2014 and NEPA analysis and refinement of the project design is planned for 2015. None of these restoration activities would occur in VCU 7450, the VCU in which the Swan Lake Expansion Project is located.

Literature Cited ADNR DOF (Alaska Department of Natural Resources Division of Forestry). 2013. Draft Coastal

Region’s Southern Southeast Area Five-Year Schedule of Timber Sales. Alaska Department of Natural Resources, Division of Forestry Southern Southeast Area Office, Ketchikan, Alaska.

USDA Forest Service (U.S. Department of Agriculture, Forest Service). 2009. Decision Memo and Finding of No Significant Impact for the Ketchikan-Misty Fiord Ranger District Access and Travel Management Plan Environmental Assessment. Ketchikan-Misty Fiord Ranger District, Tongass National Forest.

USDA Forest Service. 2013a. Tongass National Forest 5-year Timber Sale Schedule. Tongass National Forest.

USDA Forest Service. 2013b. Tongass National Forest 5-year Pre-commercial Thinning Plan-Service Contracts. Tongass National Forest.

USDA Forest Service. 2013c. Tongass National Forest 5-Year Forest Road Improvement/Maintenance Plan - Construction/Service Contracts. Tongass National Forest.

USDA Forest Service. 2013d. Tongass National Forest 5-year Fish, Watershed, Soils Project Schedule, Tongass National Forest.


Appendix B – Response to Agency Comments on the Final Wetland Resource Report


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Item Agency / Date Comment Response GENERAL COMMENTS (applies to all Resource Reports)

1 USFS, February 20, 2014

All resource reports, except the three botanical reports, list the Proposed Action under Environmental Consequences. When preparing the Preliminary Draft Environmental Assessment, consider reviewing the CEQ 1508 regulations to be consistent with the four required areas of an environmental assessment.

Comment noted


Except for shaded comments, all comments to Draft Resource Reports were addressed and are not included in this document. Additional comments are made to ensure the environmental analysis document is adequate.

Comment noted; see below for responses to all additional comments received.

WETLANDS RESOURCE REPORT 3 USFS, February

20, 2014 Page 4 1.2.1 Tongass Land and Resource Management Plan Listing of WET S&Gs. Alphabet is incorrect.

Alphabetization fixed.


Page 14 1.2.3 Consultation with U.S. Army Corps of Engineers. Final plans, supporting design report, and additional information regarding wetlands resources in the Project area may be used by USACE as a “pre-application” to advise SEAPA whether permits will be required. If permits are required, additional work delineating wetlands will be needed. A “no permit required” letter would be issued if appropriate. Request the letter specifically reference the 26 acres of wetlands on National Forest System lands.

Text added to reflect that a “no permit required” letter, if issued by the USACE, would specifically reference the 26 acres of wetlands on NFS lands.


Page 5 1.3 Analysis Area Show the cumulative effects analysis area on one of the maps.

Figure added.

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