Final

Packwood Lake Drawdown Study Report

For Energy Northwest's Packwood Lake Hydroelectric Project FERC No. 2244 Lewis County, Washington

Submitted to

P.O. Box 968 Richland, Washington 99352-0968

Submitted by

EES Consulting

1155 North State Street, Suite 700 Bellingham, Washington 98225 360.734.5915 phone, 360.734.5918 fax

July 2007

Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

TABLE OF CONTENTS

Section Title Page

1.0 INTRODUCTION ...... 1 1.1 Project Area and Study Area...... 1 1.1.1 Project Area...... 1 1.1.2 Study Area...... 2 2.0 STUDY GOALS AND OBJECTIVES...... 3 3.0 METHODS ...... 4 3.1 Mapping Littoral Areas Subject to Dewatering...... 4 3.1.1 Seasonal Area Dewatered ...... 5 3.2 Shoreline Erosion...... 5 3.3 Drawdown Effects on Wetlands ...... 6 3.3.1 Wetland Water Level ...... 7 3.3.2 Barometric Pressure and Altitude Correction...... 9 3.3.3 Lake Level and Inflow...... 9 4.0 RESULTS 9 4.1 Littoral Mapping ...... 9 4.2 Seasonal Dewatering...... 15 4.3 Shoreline Erosion...... 18 4.4 Vegetation Cover Types for Wetlands...... 25 4.5 Wetland Connectivity...... 30 4.5.1 Piezometers...... 30 4.4.2 Lake Level and Inflow...... 32 4.4.3 Piezometer Water Level, Lake Level, and Inflow ...... 33 5.0 DISCUSSION...... 48 5.1 Drawdown Area...... 48 Shoreline Erosion...... 50 5.2 Wetland Connectivity...... 50 6.0 LITERATURE CITED ...... 55

Appendix A Piezometer Images Appendix B Lake Elevation and Inflow 2001 – 2006 Appendix C Lake Level Exceedance Curves Appendix D Semi Quantified Wetland Assessment Forms

i Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

1.0 INTRODUCTION

Energy Northwest operates the Packwood Lake Hydroelectric Project (Project) near the town of Packwood in Lewis County, Washington. On November 12, 2004 Energy Northwest filed a Notice of Intent (NOI) to file an application for a new license to operate the hydroelectric project. Energy Northwest also concurrently filed with the Federal Energy Regulatory Commission (FERC) and the resource agencies, a Pre-Application Document (PAD), containing existing, relevant, and reasonably available information describing the existing environment and the potential effects of Project facilities and operations. Additional studies of the potential effects of drawdown on wetlands and other natural resources were requested to supplement information contained in the PAD (WDFW 2005, USFS 2005).

Energy Northwest, in consultation with tribes and agencies, developed and implemented a study plan to evaluate the potential effects of drawdown of Packwood Lake as part of Project operations (EES Consulting 2005). This report provides drawdown study results monitored between September 2005 and November 2006.

1.1 Project Area and Study Area

1.1.1 Project Area

Packwood Lake lies within the Gifford Pinchot National Forest in the Cascade Mountains, east of the town of Packwood (Figure 1.1). The Project facilities at Packwood Lake include an intake canal, a concrete drop structure, and an intake building on Lake Creek located about 424 ft downstream from the outlet of Packwood Lake. The drop structure, located adjacent to the intake structure, extends 85 ft in width and is tied into impervious earth fill cutoff walls on each side extending to the natural embankment.

The total area drained by Lake Creek and Packwood Lake is approximately 19.2 square miles. The Project seasonally regulates the lake level so that it is at elevation 2,857.0 ft MSL ±0.50 ft in summer recreation months and drawn down to no lower than elevation. 2,849.0 ft MSL during the winter months. This provides 8 ft of vertical storage usable by the Project. The Project is st operated to achieve a lake elevation of 2,857 MSL +0.50 ft by May 1 of each year. This level is maintained until September 15 when drawdown may begin. When lake level rises above the drop structure crest elevation of 2858.50 ft MSL, the flow passes over the drop structure into Lake Creek downstream of the lake. The influence on lake level exerted by the Project is approximately one-half inch per hour at maximum capacity (260 cfs), assuming no inflow. This effect can be easily reduced or offset by large inflows.

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Figure 1.1 – Energy Northwest’s Packwood Lake Hydroelectric Project is located in the Cowlitz River watershed, tributary to the Lower Columbia River in southwest Washington State (source Energy Northwest 2004).

1.1.2 Study Area

The study area includes Packwood Lake, surrounding shoreline up to the Project boundary inclusive of two wetland complexes adjacent to the lake (Figure 1.2). One wetland complex is located at the head of Packwood Lake and encompasses an area adjacent to Muller Creek and Upper Lake Creek. The second wetland complex is located along the southwest shoreline of Packwood Lake and includes an area adjacent to Osprey Creek.

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2

Osprey Creek

1

Upper Lake Creek Muller Creek

Figure 1.2 – The study area includes Packwood Lake and associated wetlands: (1) at the head of the lake adjacent to Upper Lake Creek and Muller Creek, and (2) on the southwest shore of the lake adjacent to Osprey Creek.

2.0 STUDY GOALS AND OBJECTIVES

The goal of the drawdown study is to identify impacts to fish, wildlife, shorelines, and associated wetlands, due to Project-related drawdown and associated fluctuating reservoir levels. Objectives include:

1. Determine acres of drawdown zone exposed at various seasonal pool levels and evaluate impacts to fish and wildlife;

2. Determine if the wetlands are hydrologically connected to lake levels;

3. Determine if Project operations are impacting the wetland complex near Upper Lake Creek;

4. Investigate shoreline erosion associated with Project operations;

5. Evaluate the rate at which the reservoir is drawn down and if resources are being impacted; and,

6. Assess direct and indirect effects of Project drawdown on fish and wildlife.

This report describes the physical effects of drawdown on lake level, wetland hydrology and erosion. An analysis of direct and indirect effects of Project drawdown on fish and wildlife as well as other resources will be addressed in the synthesis report prepared by Energy Northwest.

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3.0 METHODS

3.1 Mapping Littoral Areas Subject to Dewatering

Bathymetric data were collected at 31 transects each located perpendicular to the shoreline. Shorelines include Agnes Island in Packwood Lake. The placement of transects along the shoreline was based on variability of littoral habitat. Transect density was greater in areas with broad littoral habitats.

The data collection system consisted of a Trimble Pathfinder Pro XRS differential GPS receiver, an interfaced digital depth sounder, and an autolevel. Depth and coordinate data were stored in a Trimble TSC1 data logger and later exported to a computer for analysis and creation of map products.

The shoreline endpoint of each transect was located by using the autolevel to survey elevation 2,859.0 ft MSL relative to the day’s lake water surface elevation. The natural high water elevation of the lake is 2,859 ft MSL. This endpoint and each subsequent station along a transect were geo-referenced using the Trimble Pathfinder Pro XRS differential GPS receiver. The autolevel was used to survey the elevation of other points along the transect that were above the lake water surface. A sounding line was used to locate the longitudinal position of transect points below the water surface; these points were established at 1 ft vertical increments to a submerged elevation of 2,849.0 ft MSL.

Substrate size composition were noted along each transect using WDFW substrate codes (WDFW 1996 – Table 3.1). Substrate coding uses the WDFW convention of xy.z where:

x = the dominant substrate y = the subdominant substrate z = the percentage of the dominant substrate as compared to the subdominant substrate.

For example, a substrate coded 36.8 would denote a dominant substrate of small gravel, a subdominant substrate of small cobble, with 80% of the two substrates being small gravel. A substrate that was exclusively one substrate type would be coded XX.9. For example, substrate that was all small cobble would be coded 66.9.

Table 3.1 – Substrate Codes Code Substrate Description Mm Inches 0 Organic Detritus NA NA 1 Silt, Clay <2 < 0.1 2 Sand <2 < 0.1 3 Small Gravel 2 – 12 0.1 – 0.5 4 Medium Gravel 12- 38 0.5 – 1.5 5 Large Gravel 38 – 76 1.5 - 3.0 6 Small Cobble 76- 152 3.0 – 6.0 7 Large Cobble 152 – 306 6.0 – 12.0 8 Boulder > 305 > 12.0 9 Bedrock

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Transect data were superimposed on the 1994 Washington Department of Natural Resources (WDNR) aerial photo for Packwood Lake within a Geographic Information System (GIS). Use of the 1995 Washington Department of Ecology (WDOE) bathymetric map was initially planned; however, the contours shown in this map did not align well with the aerial photo. Therefore, the WDOE contour data (10 ft increments) were not used. Arcs were drawn between transect data points to construct the bathymetric contours. The shape of the arcs between data points was generally similar to the shoreline although some data points were connected by simply drawing straight lines between the points.

3.1.1 Seasonal Area Dewatered

The lake bathymetric GIS layer for littoral areas was used to compute the area below elevation 2,857 ft MSL that is dewatered relative to water elevation within the operational range (2857 ft MSL to 2849 ft MSL). The area dewatered due to Project operation is reported as monthly maximum, minimum and mean values. An annual exceedence curve for the dewatered area was computed based on the period of record (June 20, 1967 to present).

3.2 Shoreline Erosion

Historic aerial photographs and oblique photos of the Packwood Lake shoreline were evaluated to assess historic shoreline erosion rates and locations of any mass wasting features. Photos were observed using a stereograph to aid in the determination of topography and mass wasting areas. Nine sets of photos were available from the Washington State Department of Transportation (Table 3.2). Air oblique photos were available from March 15, 1983. In addition, 1973 and 1958 (pre-project) aerial photographs were obtained from the US Forest Service (USFS).

Table 3.2 – Historic Aerial Photographs Used in Drawdown Zone Analysis Date Lake Elevation (ft MSL) Scale 9/6/58 Pre-project approx. 1:15,000 7/19/73 2856 1:20,000 3/15/83 2,856 1:5,000 6/1/84 2,856 1:5,000 6/11/85 2,858 1:5,000 5/16/86 2,856 1:5,000 5/6/87 2,856 1:5,000 5/24/88 2,857 1:5,000 10/24/90 2,858 1:5,000 10/4/91 2,849 1:5,000 10/5/92 2,850 1:5,000

A field inventory of the Packwood Lake drawdown zone and shoreline was conducted on September 28, 2005 (lake elevation 2,850 ft MSL). The inventory was conducted by boating and walking around the lake shoreline. The field work included observations of substrate in the drawdown zone, searching for indicators of erosion in the drawdown zone (such as exposed tree roots, rills, etc – there was little evidence of recent erosion outside of the delta areas.), as well as observations of erosion on the lake shoreline (such as steep banks of exposed soil, tree toppling,

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landslides, etc.). These features were mapped in the field on the 1992 aerial photographs and transferred to the bathymetric map of the lake for digitizing.

A map of shoreline erosion and deposition was prepared based on the field inventory and aerial photograph evaluation. The map includes substrate in the drawdown zone and erosion/deposition potential based on the substrate classification, field observations, and subsequent analyses of potential wave erosion.

A request was made to quantify potential erosion of substrate in the drawdown zone based on particle size and wave energy. While a large body of literature and methods exist to quantify erosion on sandy beaches, little information was found on methods to quantify erosion on gravel to cobble beaches in low energy environments such as Packwood Lake. The closest analogy found was a dissertation by Finlayson (2006) on beaches in Puget Sound.

Wind-induced waves are the primary source of wave erosion energy in Packwood Lake. The size and period of wind waves was calculated based on the fetch (length of open water; 1.8 km/1.1 mile between Agnes Island and the upper end of the lake, and 0.7 km/0.4 mile across the lake), average water depth (30.5 meters/100 ft), and a variety of wind speeds. The maximum average daily wind speed recorded at the weather station at the intake structure between 2004 and 2005 was 4.3 mph (1.92 m/s); the maximum daily wind speed was 9.7 mph (4.34 m/s). Additional wave heights were computed for speeds of 20 mph (9 m/s), 30 mph (13 m/s), 40 mph (18 m/s) and 50mph (22 m/s). Wave height and period were computed based on the algorithms in Sherwood (2006).

The equations in Finlayson (2006) were used to estimate the inception of motion of gravel (16 mm/0.63 in.) and cobble (64 mm/2.5 in.) particles. Inception of motion was assumed when the ratio of the shear velocity (u*) to the settling velocity (vs) exceeded 0.2. The settling velocity for gravel was calculated as 2.4 ft/sec (0.72 m/s) and cobble was calculated to be 4.1 ft/sec (1.24 m/s) based on algorithms in Sherwood (2006). The shear velocity in shallow, nearshore water (depth 0.1 m/0.3 ft) was calculated based on the calculated bottom velocity and wave friction factor for the different wind waves described in the preceding paragraph. Please refer to Finlayson (2006) Chapter 5 for a complete description of calculations used for this analysis.

3.3 Drawdown Effects on Wetlands

There are two known large wetland complexes in close proximity to Packwood Lake. This study investigated the level of hydrologic connectivity between the lake level and groundwater in these two wetlands. An assessment of the character and functions of these wetlands was also part of this study.

Vegetation cover-type mapping was completed as part of the Revised Vegetation Cover Type Mapping Study Plan. Methods for cover type mapping are described in the Study Plan (Energy Northwest 2005); field work was completed in July 2006. The cover-type mapping delineated the approximate boundaries and classifications for wetlands adjacent to Packwood Lake. The cover type mapping report also provided information on plant species composition inventoried at samples plots within the wetlands adjacent to Packwood Lake. Concurrent with ground truthing

6 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244 vegetation cover, biologists conducting the cover type mapping also noted observed and potential wildlife use. Information from the cover type mapping report (DTA 2006) was integrated with the results from the drawdown study in order to complete functional assessments of the wetlands using the Semi-quantified Assessment Method (SAM) (Cooke Scientific Services, Inc. 2000).

3.3.1 Wetland Water Level

On September 14, 2005 six piezometers were installed in monitoring wells in the two known wetlands. All monitoring wells were constructed within 500 linear ft of Packwood Lake. Monitoring wells were constructed in pairs, with one situated closer to the lake than the other. Four wells were established in the wetland complex at the head of Packwood Lake; two were located near Muller Creek, and two near Upper Lake Creek (Figure 3.1). Two monitoring wells were also installed in the wetland complex near Osprey Creek (Figure 3.2). An additional piezometer was installed within the Upper Lake Creek wetland complex in June 2006 in order to verify the results of nearby piezometers as well as investigate local variability in wetland hydrology. Map locations for monitoring wells in Figures 3.1 and 3.2 are approximations as heavy forest canopy precluded the use of GPS to map planar position.

Figure 3.1 – Piezometers 1 and 2 installed at the head of Packwood Lake adjacent to Muller Creek. Piezometers 3, 4 and 7 installed at the head of the lake adjacent to Upper Lake Creek.

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Baralogger® 

Piezometer 5 r s Piezometer 6

Figure 3.2 – Piezometers 5 and 6 installed in the Osprey Creek wetland complex on the southwest side of Packwood Lake. A Baralogger® was deployed at the existing weather station situated near the intake structure at the outlet of Packwood Lake.

Each monitoring well included a Campbell screened well point, associated 1.5-inch diameter steel piping, couplings and vented cap (see Appendix A for images). Elevation of each monitoring well head was surveyed relative to a benchmark and lake level using an autolevel and stadia rod. Well head elevations were calculated to within +0.01 ft accuracy, based on the known lake level and a benchmark reference at the time of survey. Well head elevation was referenced to estimate level logger and initial water level elevation, relative to known lake level.

Initial water level within each piezometer was determined with the wetted tape method: a dip stick with gauging paste was used to measure the distance from the known elevation of the well head to the water level. The elevation of initial water level was estimated by subtracting the depth to water from the well head elevation.

A Solinst Levelogger® F30 (Levelogger®, electronic datalogger) suspended from the vented cap of each monitoring well recorded water level at 1 hour intervals. Level loggers were suspended at a point close to the bottom of the well point. Level logger elevation was estimated by subtracting the length of cable, used to suspend the level logger, from the well head elevation.

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3.3.2 Barometric Pressure and Altitude Correction

Water level data recorded with a Levelogger® must be corrected for atmospheric (barometric) pressure and altitude. These corrections are necessary because the level loggers utilize pressure transducers to measure water level, and pressure varies with elevation and barometric pressure.

A Solinst Baralogger® (Baralogger®) was deployed at the Packwood intake site (Figure 3.2) at the same time the piezometers were installed. The Baralogger® was used to record barometric pressure and air temperature at the lake. Barometric correction was made by subtracting the atmospheric pressure, as measured by the Baralogger®, from the piezometer water level measured by each Levelogger®.

Altitude correction was made by subtracting the elevation-corrected barometric offset value from the water level measured by each Levelogger®. Elevation-corrected barometric offset was calculated as follows:

(Barometric offset at MSL) – (Level logger elevation/1000) = (Elevation-corrected Barometric Offset)

where the standard Barometric Offset value is 31.17 ft.

3.3.3 Lake Level and Inflow

Energy Northwest continuously records lake level (+ 0.01 ft MSL) using a Stevens® strip chart for a Type A, Model 71 water level recorder. Project staff also manually record lake level and estimated total inflow (cfs) to Packwood Lake on a daily basis. Beginning in June 2006, a Solinst Levelogger® F30 (Levelogger®, electronic datalogger) was installed in the stilling well at the intake; this level logger was programmed to record lake level at 15 minute intervals.

Inflow data are from the Project operations database as recorded daily at 7am. Inflow is the cumulative inflow to Packwood Lake and was not specific to the sub-basin that a wetland was located within. Inflow was calculated as:

Daily inflow (cfs) = (24-hr ∆ Lake volume ft3)/86,400 sec + avg. daily project flow + avg. daily fish release flow

Inflow is a function of precipitation, snow melt and groundwater discharge.

The weather station at Packwood Lake did not measure precipitation. Precipitation data collected by the National Climate Data Center (NCDC) co-op station located in Packwood were used to estimate daily precipitation at Packwood Lake.

4.0 RESULTS

4.1 Littoral Mapping

The location of transects are shown on Figure 4.1. Contours were created by interpolation between elevation points and following a similar shape to the previously mapped 10 ft contours.

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Surveyed elevation data fit well with the Project boundary previously mapped at 2860.0 ft MSL. The Project boundary map around the lake was based on an approximation from existing topographic data available from USGS. Figure 4.2 shows the resulting bathymetric map for littoral habitat in Packwood Lake. The elevation contours are at 1 ft increments between 2849.0 ft MSL and 2859.0 ft MSL. The uppermost contour band (white) is the Project boundary at approximately elevation 2860 ft MSL. Figures 4.3 and 4.4 provide higher resolution maps of littoral habitat at the upper end of the lake and at the mouth of Osprey Creek, respectively.

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Figure 4.1 – Map of Packwood Lake illustrating transect locations and data points (green dots) and Project boundary (white).

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Figure 4.2 – Bathymetric Map of Packwood Lake Littoral Habitat. Uppermost contour (white) is Project boundary; other contour intervals shown at 1 ft increments between 2859 ft and 2849ft.

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Figure 4.3 – Bathymetric Map of Littoral Habitat at upper end of Packwood Lake. Uppermost contour (white) is Project boundary; other contour intervals shown at 1 ft increments between 2859 ft and 2849 ft.

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Figure 4.4 – Bathymetric Map of Littoral Habitat near Mouth of Osprey Creek. Uppermost contour (white) is Project boundary. Other contour intervals are shown at 1 ft increments between 2859 ft and 2849 ft.

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Table 4.1 lists the total surface area of Packwood Lake (acres) at various water surface elevations as computed from the GIS contour map (Figure 4.2). The total lake surface area as calculated in Table 4.1 is slightly less than the previously reported surface area (Energy Northwest 2005). The Project is operated to maintain a lake elevation of 2,857 ft + 0.5 ft in summer months. Beginning in mid-September, the lake is drawn down to no lower than 2,849 ft. The lake level rises with natural inflow during the Project shutdown period in October. If the lake is lowered to the minimum allowed elevation of 2,849.0 ft MSL at the beginning of the Project annual outage; this results in 34 acres being temporarily dewatered. This is a 7.7% reduction in surface area of the lake relative to the surface area at 2,857.0 ft.

The change in surface area of the lake bed dewatered as a function of lake surface elevation was calculated for both the horizontal planar area and the slope surface area. The differences between horizontal planar area and slope surface area were less than 0.1%.

Table 4.1 – Surface Area for Packwood Lake and Acreage Affected by Drawdown Acreages per 1-foot contour between El. 2859 and 2849.

Water Surface Surface Area Change in Area Net Change in Area Elevation (acres) (acres) relative to El. 2857 (ft ) (acres) 2859.0 455 0 -13 2858.0 448 7 -6 2857.0 442 6 0 2856.0 437 6 5 2855.0 431 6 11 2854.0 427 4 15 2853.0 422 5 20 2852.0 418 4 24 2851.0 415 3 27 2850.0 411 4 31 2849.0 408 3 34

4.2 Seasonal Dewatering

Energy Northwest monitors lake level for Packwood Lake. The lake level is drawn down in the latter half of September in advance of the Project shutdown that occurs in October for maintenance. The license provides for Energy Northwest to utilize up to 8 vertical ft of storage in Packwood Lake for energy production during September 15th through April 30th. Spill occurs when inflow exceeds Project operational needs and the lake level reaches at least 2858.5 ft MSL. Figure 4.5 shows the fluctuation in lake level for the period September 2005 through November 14, 2006. Figure 4.6 shows the relationship between lake level and surface area. This relationship was used to plot the daily change in lake surface area for September 2005 through November 14, 2006 (Figure 4.7). An increase in lake surface area corresponds to a rising lake level and a reduction in the amount of exposed lake bed. Table 4.2 lists the monthly average and range for daily change in area of exposed lake bed. The rate of change and total daily fluctuation is a function of both Project operation and natural inflow. The largest daily change observed for

15 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244 a single day change is 24.4 acres, which corresponds to a rapid rise in lake level on November 6, 2006 that resulted in the lake rising from 2854.9 ft MSL to 2861.12 ft MSL when the daily inflow was 1,794 cfs.

Packwood Lake Surface Area

460.00

450.00

440.00 430.00

Acres 420.00

410.00

400.00 5 5 5 5 6 6 6 6 6 6 6 6 6 6 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 9 0 1 2 1 2 3 4 5 6 7 8 9 0 1 1 1 1 1 1

Figure 4.5 – Water Surface Level for Packwood Lake September 2005 through November 2006.

Figure 4.6 – Surface Area (acres) as a Function of Water Surface Elevation for Packwood Lake.

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Packwood Lake Daily Change in Surface Area

8.00 6.00 4.00

2.00

0.00 Acres -2.00 Fall Drawdown -4.00 -6.00 5 5 5 5 6 6 6 6 6 6 6 6 6 6 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /2 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 9 0 1 2 1 2 3 4 5 6 7 8 9 0 1 1 1 1 1 1

Figure 4.7 – Daily Change in Surface Area (acres) for Packwood Lake September 2005 through November 2006. Data are reported relative to acreage at 2857.0 ft.

Table 4.2 – Daily Change in Acres of Exposed Lake Bed for Packwood Lake: September 2005 through November 2006 Daily change in acres of exposed lake bed1 Month Maximum Mean Minimum Sep-05 5.1 1.0 -0.6 Oct-05 -0.3 -0.7 -2.0 Nov-05 1.2 0.0 -3.0 Dec-05 1.5 -0.1 -3.5 Jan-06 2.1 -0.5 -7.7 Feb-06 1.2 0.2 -0.7 Mar-06 0.6 0.3 0.0 Apr-06 0.6 -0.3 -3.6 May-06 1.3 -0.2 -6.3 Jun-06 2.1 0.2 -4.2 Jly-06 3 0.2 -1.8 Aug-06 0.5 0.1 -1.0 Sept-06 4.6 1.0 -1.0 Oct-06 0.8 -0.4 -1.0 Nov-062 1.4 -2.2 -24.4 1 A negative value indicates the area of exposed lake bed was reduced due to a rising water level from the previous day 2 Partial month

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Table 4.3 lists the area of exposed lake bed below elevation 2,857 ft MSL, which is the lake level for summer months. The average monthly lake level in January and February 2006 was above 2,857.0 ft. The maximum area dewatered below 2,857.0 ft was 32.5 acres, which occurred on October 1, 2006 at the end of the fall drawdown when the lake reached an elevation of 2849.55 ft MSL.

Table 4.3 – Area (acres) below 2,857.0 ft Dewatered for Packwood Lake: September 2005 through November 2006 Acres of exposed lake bed1 Month Maximum Mean Minimum Sep-05 31.6 12.1 -0.6 Oct-05 29.8 20.7 10.4 Nov-05 9.8 8.7 6.2 Dec-05 22.8 15.7 6.8 Jan-06 4.0 -4.4 -11.6 Feb-06 -3.6 -6.8 -9.5 Mar-06 5.0 1.0 -3.0 Apr-06 5.6 3.5 -3.6 May-06 -2.4 -8.1 -13.0 Jun-06 -2.4 -8.5 -13.0 Jly-06 0.0 -2.6 -8.1 Aug-06 2.5 1.1 0.0 Sept-06 32.2 11.2 0.5 Oct-06 32.5 26.1 20.8 Nov-062 21.6 1.2 -13.0 1 A negative value indicates the lake level was above 2,857.0 ft MSL 2 Partial month

Monthly exceedance curves for the lake elevation were computed based on the period 1971 – 2006 (see Appendix C.) The 50% exceedance elevation for May through August is at 2857.0 ft +0.1 ft. The 50% exceedance elevation is 2856.5 ft and 2852.5 ft, respectively, for September and October.

4.3 Shoreline Erosion

Project operations include seasonal fluctuations of the lake between elevation 2,857 ft MSL and a low surface elevation (2,849 ft MSL), with occasional higher water levels during floods and overtopping events (top of drop structure at 2,858.5 ft MSL). Daily lake level elevation data from 1999-2006 are shown on the graphs in Appendix B. Potential lake shoreline erosion associated with Project operations includes:

• Surface erosion and wave-induced erosion in the exposed drawdown zone; • Stream deposition and erosion at the mouths of tributaries as streams deposit sediment in deltas at the lake edge and then cut through the deposits at lower lake levels; and

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• Slides along the reservoir banks associated with rapid water level fluctuations. This type of erosion mechanism only occurs if steep banks of fine-grained (low permeability) material are saturated at high reservoir levels, reservoir levels are lowered rapidly enough that the water cannot drain quickly enough out of the saturated bank, and the saturated material is left unsupported. These conditions were not observed in Packwood Lake; there were no high banks of unconsolidated fine-grained materials, and water levels do not drop rapidly enough to leave banks saturated and unsupported (maximum drawdown rate 1999-2006 was 0.5 inches/hour). No evidence of erosion of banks due to rapid reservoir level fluctuations was observed.

Natural bank erosion processes such as undercut banks and tree toppling associated with wave action at full pool levels occur; however, these types of erosion processes would occur with or without Project operations because Packwood Lake is a pre-existing lake.

Current and potential future erosion of the Packwood Lake shoreline and drawdown zone was evaluated based on historic aerial photographs and field visits during low lake levels. Field observations indicate that past lake level fluctuations have moved most of the more erodible fine- grained material (clay, silt, fine sand) from the drawdown zone into deeper areas of the lake. Little evidence of recent erosion in the drawdown zone (such as rills) was seen except in areas of active erosion and deposition in tributary deltas. A map of shoreline erosion was prepared showing existing substrate in the drawdown zone, existing mass wasting locations, and the potential for future erosion (Figure 4.8).

Future erosion potential was based primarily on the size of substrate exposed along the shoreline and the visual evidence of erosion observed (or the fact that no evidence of recent erosion was observed) during field investigations. In addition, the potential for wave erosion from wind- induced waves in the lake was investigated for gravel (16 mm/0.63 in.) and cobble (64 mm/2.5 in.) particles. Maximum wave height would come from wind blowing lengthwise up or down the lake (toward either the southeast or northwest) since this would provide the longest fetch between Agnes Island and the upper end of the lake. The wind often blows in these directions as shown on the wind direction diagram in the upper right hand corner of Figure 4.8 (showing the relative number of days with average wind directions). Smaller wave heights would come from wind blowing across the lake; cross-lake winds are also common. Based on the estimated wave heights required to initiate movement of gravel and cobble-sized particles, wind speeds of 20 mph (9 m/s) would be needed to initiate gravel transport and speeds of 35 mph (16 m/s) would be needed to initiate cobble transport if the wind was blowing lengthwise down the lake. Wind speeds of 35 mph (16 m/s) and over 50 mph (22 m/s) would be needed to initiate transport of gravel and cobble, respectively, for winds blowing across the lake. The maximum daily wind speed recorded in 2004-2005 at the Packwood Lake weather station was 14 mph (4.34 m/s). The weather station is located at the intake, which is wind sheltered by topography and trees relative to the lake. Higher winds speeds and gusts certainly occur infrequently during storms. However, the wind speed calculations support the hypothesis that the gravel and cobble beaches are not erodible under normal wind conditions.

The wave erosion estimates are based on waves hitting a relatively straight shoreline, typical of much of the upper end of Packwood Lake. Wave energy is always higher on headlands that

19 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244 protrude out into the lake, and lower in protected bays as waves are refracted by irregular shorelines. The shorelines in the downstream (outlet) portion of the lake, downstream from Agnes Island, are also more protected since wind and wave energy is dissipated by the island. These findings are consistent with field observations of finer-grained material (sand/gravel mix) on more protected areas of the lake.

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Wind Direction 2004-2005 (wind blowing toward) N

NW NE

W E

SW SE

S

Figure 4.8 – Shoreline Erosion Potential and Mass Wasting Sites for Packwood Lake.

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Five different substrate/erosion potential categories were mapped in the field. Figure 4.9 shows photos with examples of each of these categories.

• Bedrock – No erosion potential. Bedrock is exposed in the southwestern portion of Packwood Lake. This area has no future erosion potential. Total length: 1,809 feet (8% of shoreline length); Total area: 1.4 acres (4% of drawdown area).

• Gravel/cobble/boulder – Low erosion potential. Much of the drawdown zone is armored by a mix of gravel, cobble, and boulders. The substrate is large enough that it resists surface erosion during rainfall events and erosion by waves as lake levels fluctuate. No evidence of recent erosion was observed in these areas. It is possible that some slow erosion will occur in these areas during the term of the new license, (primarily during large wind storms when the lake is drawn down) but the future erosion potential is low. Total length: 13,186 feet (58% of shoreline length); Total area: 19.7 acres (51% of drawdown area).

• Sand and gravel – Moderate erosion potential. There are several sites, primarily in protected bays and at the mouths of very small tributaries, where sand dominates the substrate. These areas are likely to have some surface erosion associated with Project operations in the future, but since these sites are somewhat protected either in bays or in areas where the fetch is limited, erosion will not likely be very rapid (several of the sites had some gravel armor). There was minor, local evidence of recent erosion in these areas. Total length: 4,155 feet (18% of shoreline length); Total area: 5.4 acres (14% of drawdown area).

• Sandy – active stream delta erosion and deposition. The mouths of three of the largest tributaries have active deltas. These areas include the mouths of Lake/Mueller creeks, Osprey Creek, and the bay north of Osprey Creek. These creeks are building deltas in Packwood Lake. Sediment is deposited just below water level, resulting in a moving zone of deposition between full pool and low pool elevations. When the lake level is below full pool, the streams cut through the deposits and transport the sediment to the current pool level. The Upper Lake Creek delta is also exposed to full-fetch wind waves. The result is a zone of very active and varying erosion and deposition. Total length: 3,433 feet (15% of shoreline length); Total area: 12.1 acres (31% of drawdown area).

• Mass wasting sites – location of past slides. Two landslides were observed around the lake shore. The largest of these slides is located on the northeastern side of the lake. This historic slide occurred prior to the Project (it is present on the 1959 aerial photographs). This slide is not related to Project operations since the slide occurred prior to Project initiation, and there is a standing line of mature trees along the lake shoreline at the toe of the slide. It appears that the slide initiated upslope of the lake and the toe/run- out zone just reaches the full pool shoreline. Wave action at full pool levels may undercut the toe of the slide in the future, but this would not be related to Project operations, and major erosion would be needed to topple the standing timber and remove all root strength in the toe. The toe of the slide does not extend below full pool (there is a gently sloping sand/gravel/cobble beach in the drawdown zone at this location). Water

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level fluctuations are not anticipated to affect this slide since the toe does not extend into the drawdown zone, and the rapid permeability of the sand/gravel/cobble beach would allow water in the soil to drain rapidly so that oversaturation of the toe is not likely.

The other slide is on the west side of Agnes Island. This is a small translational slide (approx. 10 ft wide, 20 ft long) in an area that has evidence of a past fire (Figure 4.9). It is possible that this slide was influenced by Project operations, but it was most likely triggered by wave action at full pool, a natural occurrence. This slide is too small to be seen on aerial photographs, so it is not know when it occurred.

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Bedrock (No Potential) Gravel/Cobble/Boulder (Low Potential)

Gravel/Sand (Moderate Potential) Sandy Delta (Active Erosion/Deposition)

Small Mass Wasting Site (Agnes Island)

Figure 4.9 – Photos of Packwood Lake Erosion Classifications

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In addition to Project-related erosion, an assessment of shoreline erosion at full pool was made by comparing the series of historic aerial photographs and observations of the banks during the field visit. There was very little change in the shoreline during the aerial photograph period. Most of the trees along the shoreline during the earliest photo (1958) were still present in the latest photo (1992). The only location where a tree appeared to be missing was on the west side of Agnes Island. This is consistent with the field observations; there was a 1-2 foot high bank anchored by tree roots around the majority of the lake, and little evidence of fresh bank erosion (no loose bare soil, freshly toppled trees, etc.). The west side of Agnes Island had the highest banks (2-5 feet) and also evidence of bank beaver activity.

Other shoreline erosion observed included trampling of banks by recreationalists in the area of the lake outlet (near the foot bridge, the old hotel site, and between the USFS old and new ranger cabins) and at several of the dispersed camping sites along the northeastern shore of the lake.

4.4 Vegetation Cover Types for Wetlands

The methods and results for vegetation cover type mapping inclusive of wetlands adjacent to Packwood Lake are reported in DTA (2006). Digital, black-and-white orthophotos were combined with existing Forest Service GIS vegetation data (available at http://www.fs.fed.us/gpnf/forest-research/gis/) to create base maps of the study area. Base maps were prepared at a resolution sufficient to show and map major vegetation types (1:6,500). The base maps with USFS cover type polygons were reviewed and field sampling points were assigned to each major cover type. Field surveys were completed to verify cover types and further characterize plant species composition.

As reported in DTA (2006), major vegetative and structural characteristics were documented using a plotless, rapid vegetation assessment method. The following data were collected at each point:

• Universal Transverse Mercator (UTM) coordinates; • Representative photograph(s); • Species and estimated cover for dominant and subdominant trees and shrubs; • Estimated diameter at breast height (DBH) of dominant trees, or height of dominants in non- forested areas; • Plant community type; • Plant association, if defined for the habitat; • Estimated local density of snags and coarse woody debris; • Potential for or occurrence of special-status species; • At wetland sites, observed source(s) of wetland hydrology; • At wetland sites, hydrogeomorphic classification (Brinson 1993); and • At wetland sites, classification of dominant wetland types (Cowardin et al. 1979).

Palustrine Forested Wetlands mapped areas were located southeast of the head of Packwood Lake (Figure 4.10). Palustrine forested wetlands southeast of Packwood Lake extend well beyond the study area boundary. Upper Lake Creek is surrounded by palustrine forested

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wetlands in the study area; as such, delineation of a separate riparian vegetation type was not feasible. The smaller tributaries of Packwood Lake are also surrounded by similar vegetation types, precluding riparian mapping. Two categories of Palustrine Forested Wetland were differentiated: Palustrine Forested Wetland-Red Alder and Palustrine Forested Wetland-Mixed. Palustrine Forested Wetland mixed wetlands were characterized by co-dominant species of red alder, black cottonwood, and western red cedar. Occasional Douglas-fir and western hemlock also occur on upland inclusions on slightly higher ground. Shrub cover ranged from about 10- 30% and was dominated by red elderberry (Sambucus racemosa) and vine maple. Herbaceous cover at sampling points was 70-90%. Herbaceous species found at Palustrine Forested Wetland sites were diverse and included lady fern (Athyrium filix-femina), skunk cabbage (Lysichitum americanum), cow-parsnip (Heracleum lanatum), Cooley’s hedge-nettle (Stachys cooleyae), mitrewort (Mitella sp.), piggy-back plant (Tolmiea menziesii), forget-me-not (Myosotis laxa), and monkey-flower (Mimulus sp.).

Brinson (1993) developed a hydrogeomorphic (HGM) classification based on the geomorphic setting, water source and hydrodynamics of wetlands. The wetland complex at the head of Packwood Lake is characteristic of a low gradient alluvial floodplain wetland with seasonal surface drainage, precipitation and groundwater seepage being the water sources. The hydrodynamics include biodirectional flow as the lake also influences the wetland hydrology. According to Brinson (1993), wetland of this category have high wildlife biodiversity and high nutrient retention.

The wetland complex adjacent to Osprey Creek includes both palustrine emergent seasonally flooded and palustrine forested wetlands dominated by red alder (Figure 4-11). Other tree species in this wetland include mountain hemlock and red cedar. A band of scirpus sp. (sedge) 10-20 wide extends back from the shoreline. There is abundant downed large woody debris thourhgout this wetland.

The wetland complex adjacent to Osprey Creek is classified as a low gradient alluvial floodplain using Brinson’s classifications. Water sources are dominated by groundwater seepage and precipitation. The hydrodynamic energy gradient is low.

Core samples of the upper 15 – 20 inches of soil within the wetlands evaluated as part of the drawdown study were collected and examined for indicators of hydrologic condition. Table 4-4 summarizes vegetation cover type (Cowardin et al., 1979), soils texture and color, and hydrologic source for wetlands near each of the peizometers. Additional information on wetland function and value using the Semi-quantified Assessment Method (SAM) (Cooke Scientific Services, Inc. 2000) is reported in Appendix D.

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Table 4-4 Summary of Vegetation cover type, soils and hydrology for wetlands near piezometers Wetland Soil Texture & Hydrologic Site Location Vegetation Type1 Color Source Muck 0-24” Shallow P-1 Palustrine Forested 10YR 2.2 groundwater affected by lake level during drier months; Near groundwater Muller Silt loam 24 - seepage Creek Palustrine Forested 28” associated 10YR 2.1 with precipitation and upslope hydrology during wetter P-2 months Clay/sand Upslope 0-22” hydrology 10YR3.2 associated Upper Lower layer = with Lake Lake P-3 Palustrine Forested gley sand Creek Creek Groundwater Gley 310Y associated P-4 & 7 Palustrine Forested Clay at 2.6 ft with lake level Organic muck 0-26” P-5 Palustrine Forested 10YR2.2 Small Groundwater Organic muck tributary seepage 10YR2.1 north of associated 0-8” Osprey with upslope Coarse sandy Creek hydrology Palustrine silt emergent and Gley 10YR6.3 P-6 Palustrine Forested 8-24” 1Cowardin et al., 1979

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Figure 4.10 Wetland vegetation map for area upstream of Packwood Lake (DTA 2006)

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Figure 4-11 Map of wetlands near Osprey Creek (DTA 2006)

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4.5 Wetland Connectivity

A total of seven piezometers were installed within two wetland complexes adjacent to Packwood Lake. Water level in the piezometers as well as lake water surface elevation were monitored and records compared to establish the response of groundwater level within the wetlands to fluctuations in lake level.

4.5.1 Piezometers

Piezometer Installation and Maintenance

All seven piezometers were installed to a depth of at least 2.25 ft below ground surface (bgs), consistent with the study plan (EES Consulting 2005). Piezometers 1 (P-1) and 5 (P-5) were set at a slightly greater depth (5.42 and 5.75 ft bgs, respectively), but still within continuity of the shallow water table associated with the wetlands. Level logger elevations were approximately 2 ft below mean lake level (2857 ft MSL) for all except Piezometer 3 (P-3). Construction of P-3 met the 2.25 ft bgs standard in the study plan, but was monitored at a higher elevation (2857.45 ft) than the other piezometers because it was constructed at a high point in the wetland. Please see the results section of P-3 for more details.

Piezometers filled with water at varying rates during construction with the exception of P-3, which was dry at the time of construction. Table 4.4 summarizes piezometer installation and setup.

Table 4.4 – Piezometer Number, Level logger Serial Number, Level logger Elevation, and Manually Measured Initial Water Surface Elevation. Level logger Piezometer Levelogger® Initial Water Level Elevation Elevation Number Number (feet above MSL) (feet above MSL) 1 71390 2855.23 2859.19 2 71355 2855.65 2857.78 3 71334 2857.445 n.a.1 4 71382 2855.54 2857.06 5 70844 2854.74 2860.38 6 71357 2855.955 2858.29 72 43649 2856.37 2858.3 1 Water level was not available (n.a.) as P-3 was dry at the time of construction. The piezometer well later filled with water as groundwater level rose with fall precipitation. 2 Installed June 16, 2006

Initial water levels collected with the wetted tape method were compared with barometric- corrected water levels measured by Leveloggers®. Manual measurements of water level at the April 19, 2006 site visit were used to calibrate the previously recorded data. Level loggers continuously recorded water level with a precision of + 0.01 ft. As piezometer water levels were

30 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

based on lake level and a benchmark reference, water levels are reliable for comparative analysis purposes in this report. They should not, however, be interpreted to represent true elevation with accuracy to + 0.01 ft relative to a mean sea level (MSL) standard.

Piezometer Monitoring

Water levels in Packwood Lake wetlands were monitored hourly for the period September 14, 2005 through November 14, 2006. Table 4.5 identifies the number of observations, the mean water level, the minimum water level, and the maximum water level for all seven piezometers.

Table 4.5 – Descriptive Statistics for Packwood Lake Piezometers including: Count, Median, Minimum and Maximum Water Level. Piezometer Number of Median Elevation (ft Min. Elevation Max. Elevation (ft Number Observations above MSL) (ft above MSL) above MSL) 1 9363 2859.73 2858.11 2861.62 2 8058 2858.71 2857.14 2861.35 3 8632 2858.68 2857.06 2861.49 4 5779 2857.30 2855.88 2861.24 5 9364 2860.21 2859.62 2861.11 6 9366 2858.45 2856.37 2861.04 71 1665 2856.72 2856.36 2861.21 1Installed June 16, 2006

The water level within each piezometer was manually measured at each site visit when downloading, deploying and retrieving instruments. These field visits occurred on September 14, 2005 (installation), November 10, 2005, April 19, 2006, June 16, 2006, August 31, 2006, and November 14, 2006. The manually measured water level was compared to the corresponding instrument reading.

Data were checked following data retrieval and barometric and altitude correction. Following data retrieval, the Levelogger® serial number, filename and data were checked to assure that records were not mixed between piezometers. Data were also checked to make sure that there were no unexplained deviations in the data time series. Lastly, data were examined for outliers. The piezometers were each calibrated before and after deployment. All of the piezometers calibrated within +0.06 ft of the true value.

Some observations were eliminated from the record during quality control and quality assurance (QA/QC) data-checks. Data were not utilized when:

• a piezometer was dry, • when data were affected by installation or retrieval, • when the Baralogger® data were not available to properly calibrate piezometer data, or outlier data for a single hour indicated erroneous data.

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Both baraloggers did not properly record data for the period June 16 through July 19, 2006. For this period, a correction factor was computed for each of the piezometer level loggers based on a back calculation of estimated barometric pressure based on the difference between the lake level reported by the Solonist level logger and the Project’s Steven’s recorder.

Piezometer 5 reported the least fluctuation in water level; the range for the entire study period was 1.5 ft. Piezometers P-4 and P-7 showed the greatest fluctuation with a range of 5.36 ft and 4.85 ft, respectively. The water levels in these two piezometers were nearly identical; however, the monitoring period was much longer for P-4.

4.4.2 Lake Level and Inflow

Figure 4.12 shows lake level and inflow to the lake for the period that the piezometers were operated. Lake level data are a compilation of the daily data reported by Energy Northwest and hourly data recorded by a SolonistTM levelogger placed in the intake stilling well; the latter source of data available beginning June 16, 2006. These two data sources had an excellent correlation (R2 = 1.00). Charts of daily lake level based on Project operations records are provided in Appendix B. Monthly lake level exceedance curves based on the period 1971 – 2006 are provided in Appendix C

In 2005, drawdown of Packwood Lake began on September 15, 2005, soon after installation of piezometers on September 14, 2005. A rapid increase in inflow to the lake beginning October 1st had little immediate effect on lake level. Lake level steadily increased through October to an average level of 2855.43 ft in November. At the end of November and early December, a smaller drawdown occurred just prior to significant inflow at the end of December and early January. Inflow peaked at approximately 439 cfs on January 10, 2006 concurrent with the lake level reaching the crest of the drop structure. Inflow decreased throughout the remainder of winter 2005/2006 prior to snowmelt runoff in the spring.

High inflow in spring 2006 and the planned overtopping resulted in the lake exceeding the drop structure crest elevation nearly continuously for the period May 17 through June 19, 2006. The lake level gradually lowered as inflow tapered off. The lake level reached 2857 ft MSL (± 0.5 ft) by July 8, 2006 where it was maintained until mid-September. During the fall 2006 drawdown, the lake elevation was lowered to a minimum 0f 2849.55 ft MSL, which was reached on October 1, 2006. The lake level steadily increased throughout October during the Project shutdown. Lake level rapidly increased at the beginning of November when a large storm event resulted in a peak inflow of 1,794 cfs. Lake level exceeded 2861 ft MSL during this storm event, which resulted in the wetlands adjacent to the lake being fully inundated.

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Packwood Lake Wetland Hydrology

2863 500

Lake Level inflow 450 2861 400 2859 350 300 2857 250 2855 (ft.) MSL 200 Inflow (cfs) Water Level Level Water 2853 150 100 2851 50

2849 0 5 5 5 0 06 06 06 06 06 0 0 0 /2 /20 /20 /2 6 19 1 0/15/200 1/15/2 2/16/200 /1 / /20/2006 /2 9/14/20051 1 1 1 2/16/20063/19/20 4 5 6/20/20067/21 8 9/21/200610/22/2006 Date

Figure 4.12 – Packwood Lake Level (ft) and inflow (cfs).

4.4.3 Piezometer Water Level, Lake Level, and Inflow

Water level data for piezometers P-4 and P-7 (near upper Lake Creek) were nearly identical with data for lake level. Water elevations in the other piezometers were generally higher than Packwood Lake level throughout the monitoring period. The median lake level was 2856.6 ft MSL between September 14, 2005 and November 14, 2006. Median wetland water level was 2859.73, 2858.71, 2858.68, 2857.30, 2860.21, 2858.45, and 2856.72 ft as measured in P-1 through P-7, respectively (Figure 4.13). With the exception of P-4 and P-7, piezometer water levels were also considerably less variable than lake level, as illustrated in Figure 4.13.

Lake level and piezometer water level were each analyzed as a function of daily precipitation data from the NCDC Coop station in Packwood. The correlations were poor (R2 < 0.1) in all cases. Correlation analyses were completed for the entire study period as well as the wet period (November through June). Inflow also did not show a good correlation with precipitation. Inflow is predominantly from upper Lake Creek. In the spring and early summer, a large portion of the inflow is from snowmelt. In winter months, precipitation falls as snow at higher elevations within the drainage basin, which contributes to a low correlation between inflow and precipitation.

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2863 WET 2 WET 4 WET 6 Lake Level 2861

2859

2857

2855

Elevation Water 2853

2851

2849 WET 1 WET 3 WET 5 WET 7

Figure 4.13 – Packwood Lake level (Lake) and wetland (piezometer, P) water levels during the 2005-2006 drawdown period. Box-whisker diagrams illustrate minimum and maximum (blue diamond), the 1st and 3rd quartile (box), median (line through box), mean (red cross), and outliers (vertical line) values for each data distribution.

Piezometer 1 (P-1)

P-1 was installed as part of a paired set at the head of Packwood Lake, adjacent to Muller Creek. Of the pair, P-1 was located farthest from the lake. The ground surface elevation at P-1 was higher than at any of the other piezometers installed at the upper end of Packwood Lake. P-1 was constructed to a depth of 5.42 ft below ground surface (bgs), and in continuity with the shallow groundwater table associated with the wetland. The well point slowly began to fill with water at the time of construction.

Water level in P-1 was generally stable throughout the monitoring period. A stepwise forward regression with lake level and inflow as the independent variables resulted in a moderate correlation between lake level and piezometer water level based on data for months July through October (adjusted R2 = 0.704, n = 150). Changes in water level and corresponding lake level during the drier summer and fall period (July 1 – October 31) can be seen in Figure 4.14. Inflow had a stronger influence on piezometer level during the wet months (November through June) (Figure 4.15). The response to lake drawdown was moderate. The water level at P1 dropped 1 ft and 1.3 ft, respectively, during the fall 2005 and fall 2006 drawdown periods. The groundwater level at P-1 was 1.4 ft below the surface just prior to the fall drawdown in 2005. The groundwater level at P-1 remained within approximately 1 ft of the surface during summer 2006 and dropped to a maximum depth of 2.35 ft below the surface during the fall 2006 drawdown.

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Groundwater level at P-1 positively responded to increased inflow/precipitation during the fall drawdown in both years. This indicates a transition from groundwater level being a function of lake level during the dry months to upslope hydrologic conditions with the onset of the fall rainy season. For example, on September 29, 2005 the wetland water level increased by almost one foot (2858.12 ft and 2859.04 ft MSL) in a 13 hour period. Between September 28 and September 30 (a 48 hour period) lake level increased only 0.02 ft (2850.03 to 2850.05). Between September 28 and September 30, inflow changed from 22 cfs to 173 cfs. Sharp increases in both inflow and piezometer water level occurred at the time of storm events on October 1, November 1 and December 24 through 26, 2005. Similarly, the first substantial storm during the fall 2006 drawdown resulted in a rapid rise in groundwater at P-1. Inflow increased from 29 cfs to 65 cfs on October 15, 2006. Water level at P-1 rose 1.2 ft within a 14-hour period. Lake level only increased 0.14 ft during this same period.

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Packwood Lake Wetland Hydrology

Piezometer 1

2863 Lake Level Piezometer 1 ground 2861 2859 2857

2855 (ft.) MSL

Level Water 2853 2851

2849

5 6 6 6 6 006 006 006 006 006 200 2005 200 /200 /2006 /200 /200 4/ 3/20053/2005 1 9 9 8 /14/ /12/2 /13/ /12/2 9/ 0/ 1/ 9 0/1 1 2/11/23 4 5/12/2 6/11/20067/1 8/10/2 1 1 1 11/1 12/1 Date

Figure 4.14 – Piezometer 1 water level (ft) and Packwood Lake Level (ft).

Packwood Lake Wetland Hydrology Piezometer 1

2863 Piezometer 1 Inflow 500 2861 450 400 2859 350 2857 300 250 (cfs) 2855 200 Inflow (ft.) MSL Water Level Water 2853 150 100 2851 50 2849 0

6 05 05 05 06 06 0 006 006 20 20 /200 2 /20 2 20 5/ 6/ 2/ 1 1 16 /19/2006 20 /21/2006 9/14/2005 1/ 2/16/20063/19/ 4 5/20/20066/ 7/21/20068/21/ 9 0/2 10/ 11/15/212/ 1 Date

Figure 4.15 – Piezometer 1 water level (ft) and Packwood Lake inflow (cfs) .

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Piezometer 2 (P-2)

P-2 was part of the paired set installed at the head of Packwood Lake, adjacent to Muller Creek. Of the pair, P-2 was closer to the lake. P-2 was constructed to a depth of 3.22 ft bgs, and in continuity with the shallow groundwater table associated with the wetland. The well point slowly began to fill with water at the time of construction. Data for this piezometer was in obvious error for the period April 19 through June 16, 2006; erroneous data were not included in the analysis.

Water level in P-2 followed a temporal pattern very similar to P-1. As with P-1, water levels were generally stable throughout the monitoring period. The ground surface at this piezometer was lower than P-1 and the soil was saturated to the surface during winter months (Figure 4.16). The groundwater level was within approximately 0.4 ft of the surface in the summer. Groundwater level dropped about 1 ft during the fall 2005 drawdown and 1.2 ft during the 2006 drawdown. The P-2 water level correlated well (R2=0.706) for the dry season (July through October) but upslope hydrology (inflow) was a stronger determinant of water level during other months. The water level at P-2 rapidly rose 1.1 ft on October 15, 2006 with the first storm event; the water level at P-2 returned to within 0.1 ft of the pre-drawdown level even though the lake level only increased 0.14 ft.

The response to lake level elevation for both P-1 and P-2 was small as demonstrated by a relatively flat slope (0.15 and 0.19 for P-1 and P-2, respectively) for the correlation between piezometer water level and lake level. Figure 4-17 shows piezometer water level at P-2 and inflow data.

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Packwood Lake Wetland Hydrology Piezometer 2 2863 2861 Lake Level Piezometer 2 ground 2859

2857

2855 2853 Water Level (ft.) 2851 2849

5 6 6 0 0 2005 2005 20 2006 2006 2006 2006 2006 /2006 20 16/ 19/ 20/ 21/ 21 9/14/ 1/ 2/16/ 3/ 4/19/20065/ 6/20/20067/ 8/21/2009/ 10/15/ 11/15/200512/16/ 10/22/

Date

Figure 4.16 – Piezometer 2 water level (ft) and Packwood Lake level (ft)

Packwood Lake Wetland Hydrology Piezometer 2

2863.00 500 450 2861.00 Piezometer 2 Inflow 400 2859.00 350 300 2857.00 w 250 (cfs) 2855.00 200 Inflo 150

Water Level (ft.) 2853.00 100 2851.00 50 2849.00 0

5 6 6 005 0 006 00 006 006 006 006 006 0 /2 2005 /2 /2 /2 /2 2 2006 4 5/2005 6/ 9 2/ 1 1 1 /16/2 /16/2 1 /21/20 2 9/ 0/ 2/ 1 2 3/19 4/ 5/20 6/20 7/21/20068/21/ 9 0/ 1 11/15/201 1 Date

Figure 4.17 – Piezometer 2 water level (ft) and Packwood Lake inflow (cfs).

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Piezometer 3 (P-3)

P-3 was part of a paired set installed at the head of Packwood Lake adjacent to Upper Lake Creek. Of this pair, P-3 was farthest from the lake. P-3 was constructed to a depth of 3.26 ft bgs, and in continuity with the shallow groundwater table associated with the wetland. Unlike P- 1 that was constructed to a greater depth because it was farther from the lake and farther upslope, P-3 was kept to the minimum construction depth to avoid perforating a clay layer found during construction of P-4. As a result, P-3 met construction criteria in the study plan (EES Consulting 2005), but was monitored at an elevation higher than the other wells (Table 4.4). The well point remained dry throughout construction. Over 700 observations were not utilized for P-3 because the well was dry during much of September and October 2005. Water levels showed more fluctuation at this site than others during the winter months. The water level at P-3 showed a gradual decline throughout the spring and summer through mid August when it stabilized until the time of the drawdown. The water level dropped about 0.6 ft during the fall 2006 drawdown but the level remained above the SolonistTM level logger elevation. The rate of drop during the drawdown was comparable to the gradual decline observed earlier in the summer. The soil was only periodically saturated to the surface at P-3 during winter months.

Water levels in P-3 were highly variable. Neither the variability nor the trends in water level closely followed lake level (Figure 4.18). Piezometer water level was poorly correlated to lake level (R2 = 0.365) for the dry months (July through October). A stepwise regression for the entire study period also showed a weak correlation (R2 = 0.53) for P-3 water level with lake level and inflow as the independent variables. Although the correlation for the entire period of record was weak, there appears to be a relationship between changes in piezometer water level and changes in inflow (Figure 4.19). For instance, spikes in piezometer water level on October 1, November 1, November 13, and December 23, 2005, October 15 and November 4-5, 2006 corresponded with significant increases in inflow to levels over 100 cfs. These corresponding events indicate that water level in P-3 was associated with groundwater in continuity with Upper Lake Creek. Fluctuations in water level of nearly 2 ft occurred that are not explained by changes in lake level. The high variability for water level at P-3 was likely a function of its close proximity to Lake Creek.

39 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Packwood Lake Wetland Hydrology Piezometer 3

2863 Lake Level Piezometer 3 Ground 2861 2859 2857 2855 2853 Water Level (ft.) 2851 2849

5 5 5 5 6 6 6 6 0 0 0 06 0 06 0 06 06 0 0 00 0 0 0 0 0 00 2 2 /20 /2 2 2 2 2 2 4/ 5/20 6 9/ 0/ 1/ 1/ 1 1 /1 /16 /1 /2 2 2 9/ 1/ 2 1 2/16/203 4/19/205 6/20/20067/ 8/21/20069/ 10/15/ 1 1 10/22/ Date

Figure 4.18 – Piezometer 3 water level (ft) and Packwood Lake Level (ft).

Packwood Lake Wetland Hydrology Piezometer 3

2863 Piezometer 3 Inflow 500 450 2861 400 2859 350

2857 300 w 250 (cfs) 2855 200 Inflo 2853 150 Water Level(ft.) Water 100 2851 50 2849 0

6 6 6 6 6 6 05 0 06 0 005 00 00 00 0 /2 /2 /2 /2 /2 /2 5 9/200 1/200 /1 /1 /2 9/14/20050/15 1/16 2/16/20063 4/19/20065/20 6/20/207 8/21 9/21/2006 1 11 12/16/2005 10/22 Date

Figure 4.19 – Piezometer 3 water level (ft) and Packwood Lake inflow (cfs).

40 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Piezometer 4 (P-4)

P-4 was installed as part of a paired set at the head of Packwood Lake, adjacent to Upper Lake Creek. Of this pair, P-4 was closest to the lake. P-4 was constructed to a depth of 3.35 ft bgs. A popping and gurgling sound was clearly audible when the auger used to drill the monitoring well perforated a clay layer at approximately 2 ft bgs indicating that a natural groundwater barrier was penetrated. The well point rapidly filled with water. At the time of construction there was no way to determine if the water in the monitoring well was anything other than that associated with the wetland, so well construction was completed and a piezometer was installed.

Water level at P-4 was highly variable, but closely tracked lake level during the monitoring period (Figure 4.20). P-4 water levels were not well correlated with inflow (Figure 4.21). P-4 went dry in both the 2005 and 2006 drawdown events. Over 3,500 observations were not utilized in the analysis because the monitoring well was dry. These dry well periods corresponded closely with the time periods when lake level was lower than the Levelogger® elevation in P-4 (2855.54 ft). Results suggest a high level of continuity between lake level and water level below the clay layer perforated by P-4. Water level in P-4 was highly correlated to lake level (R2 = 0.939). The coefficient for the regression was 0.89, which indicates a very close relationship; a coefficient or slope of 1.0 would occur if P-4 water level exactly matched lake level.

41 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Packwood Lake Wetland Hydrology Piezometer 4 2863 Lake Level Piezometer 4 Ground 2861 2859

2857

2855

Water Level (ft.) 2853 2851 2849

5 6 6 6 6 6 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 /2 /2 /2 2 /2 2 /2 6 6 9 0 1 /14/2005/15/2005 /1 1 /1 /2 /2 /22/2006 9 0 2 1/16/20062/ 3 4/19/20065/20/ 6 7/21/20068/21/ 9 0 1 11/15/20051 1 Date

Figure 4.20 – Piezometer 4 water level (ft) and Packwood Lake Level (ft).

Packwood Lake Wetland Hydrology Piezometer 4

2863 500 2861 Piezometer 4 Inflow 450 400 2859 350 300 2857 w 250 (cfs) 2855 200 Inflo 2853 150 Water Level (ft.) 100 2851 50 2849 0

5 6 6 6 6 6 0 0 0 0 0 06 006 0 0 0 006 0 0 /2005 /2005 2 2 /200 /2006 /2 /2 2 /2 /2 5 6 9 0 1 1 /19/2006/1 /20 /2 /22 9/14/20050/1 1/16/ 2/16/ 3 4 5 6/2 7 8/21/ 9/2 0 1 11/15/2012/1 1 Date

Figure 4.21 – Piezometer 4 water level (ft) and Packwood Lake inflow (cfs)

42 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Piezometer 5 (P-5)

P-5 was installed as part of a paired set adjacent to Osprey Creek on the southwest shoreline of Packwood Lake. Of this pair, P-5 was farthest from the lake. P-5 was constructed to a depth of 5.75 ft bgs, and in continuity with the shallow groundwater table associated with the wetland. The well point slowly began to fill with water at the time of construction.

Water level in P-5 was very stable throughout the monitoring period. A shift may have occurred in P-5 when data were retrieved on November 10, 2005 (Figure 4.22). Field notes indicate mud was attached to the P-5 level logger when data were downloaded. When the level logger was returned to the monitoring well, it may not have returned to the original depth, causing the stair- step appearance of the graph in November 2005.

Water level at P-5 was independent of lake level (Figure 4.23) and inflow (Figure 4.24). Lake level ranged 11.57 ft (2849.55 ft MSL to 2861.12ft MSL) during the monitoring period, while P- 5 water level remained no lower than 0.9 ft below the ground surface. Water level data in P-5 reflected a stable groundwater hydrology, most likely associated with upslope hydrology rather than lake level. Water level at P-5 was poorly correlated (R2 = 0.167) to lake level for dry months. Figure 4.25 is a scatter diagram illustrating P-5 water level versus Packwood Lake level during the monitoring period. If there was continuity between lake level and P-5 water level, one would expect to see very similar water levels in the lake and wetland throughout the monitoring period. Instead a scatter of data points occurred, generally following the median P-5 elevation of 2860.2 ft across all lake levels.

Packwood Lake Wetland Hydrology Piezometer 5

2863 2861 2859 2857

2855 2853 Water Level (ft) Water Level (ft.) 2851 2849 5 5 5 5 5 5 5 5 05 0 00 2005 2005 200 /200 /200 /200 3/ /7/2005 9/ 9 /11/ /13/200 /17 /19/200 /23 /25/200 /2 11/1/200511/ 11/5/200511 11/ 1/21/2 1/27/2 11 11 11/15/200511 11 1 11 11 1 11

Figure 4.22– Piezometer 5 water level (ft) and lake level (ft) in November 2005.

43 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Packwood Lake Wetland Hydrology Piezometer 5 2863 Lake Level Piezometer 5 Ground 2861

2859 2857 2855

Water Level (ft.) 2853

2851

2849 6 6 05 05 0 005 006 006 00 00 006 006 006 2 20 2 2 /2 2 2 2 2 4/2 5/ 6/ 1 1 1 /20 /20/ 9/ 1/16/ 2/16/ 3/19/20064/19/20065 6 7/21/ 8/21/ 9/21/ 10/15/2005 11/ 12/ 10/22/2006 Date

Figure 4.23 – Piezometer 5 water level (ft) and Packwood Lake Level (ft)

Packwood Lake Wetland Hydrology

Piezometer 5 2863 500 Piezometer 5 Inflow 450 2861 400 2859 350 300 2857 w 250

(cfs) 2855 Inflo 200 150 Water Level (ft.) 2853 100 2851 50 2849 0

6 6 6 00 00 00 2005 2005 2005 /2006 /2 /2006 /2006 /2 /2006 /2 2006 5/ 6/ 6 6 9 0 1 1 1 2/ /14/2005 /1 /1 /19/2006/1 /20/2006/2 /2 9 0/1 1/15/ /1 1 2 3 4 5/2 6 7 8/2 9 /2 1 1 12 10 Date

Figure 4.24 Piezometer 5 water level (ft) and Packwood Lake inflow (cfs).

44 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Packwood Lake Level vs. P-5 Water Level

2863 2861

2859 2857

2855 2853 Level Water P-5 2851 2849 2849 2851 2853 2855 2857 2859 2861 2863

Lake Level (ft)

Figure 4.25 – A scatter diagram of Piezometer 5 water level (ft) versus Packwood Lake Level during the monitoring period. The appearance of two lines on this chart is the result of a stage shift.

Piezometer 6 (P-6)

P-6 was installed as part of a paired set adjacent to Osprey Creek on the southwest shoreline of Packwood Lake. Of this pair, P-6 was closest to the lake. P-6 was constructed to a depth of 2.42 ft bgs, and in continuity with the shallow groundwater table associated with the wetland. The well point slowly began to fill with water at the time of construction.

Figures 4.26 and 4.27 illustrate changes in P-6 water level as compared with lake level and inflow, respectively. There was no correlation of piezometer water level with either lake level (R2 = 0.048) or inflow (R2 = 0.274) for the dry months (July through October). During the 2005 drawdown, water levels in the lake and piezometer both gradually decreased between September 14 and September 29, 2005. Between September 29 and September 30; however, piezometer water levels rapidly increased by more than 1 ft (from 2857.28 ft MSL to 2858.72 ft MSL). This change corresponded with a change of lake level of only 0.02 ft (from 2850.03 MSL to 2850.05 MSL) between September 28 and September 30. The rapid change in piezometer water level was associated with a spike in inflow due to a precipitation event (Figure 4.27). Inflow changed from 22 cfs to 173 cfs between September 28 and September 30. The ground remained saturated to the surface at P-6 throughout the winter and spring for 2005-2006. Water level in P-6 actually increased by about 1 ft at the onset of the fall 2006 drawdown before dropping back to a level similar to before the drawdown. Water level then rapidly rose with the onset of large precipitation events at the end of October and early November 2006.

45 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Packwood Lake Wetland Hydrology Piezometer 6 2863 Lake Level Piezometer 6 Ground 2861

2859

2857 2855

Water Level (ft.) 2853 2851 2849

5 05 05 6 6 00 006 00 006 006 00 006 006 /20 4/2 5/20 /2 6/2 9/2 /2 1/2 1/2 /1 15 1 /16 /1 /1 /20 /2 /2 9 10/ 11/ 12/16/20051 2 3 4/19/20065/20/20066 7 8 9/21/210/22/2006 Date

Figure 4.26 – Piezometer 6 water level (ft) and Packwood Lake Level (ft).

Packwood Lake Wetland Hydrology

Piezometer 6 2863 500 450 2861 Piezometer 6 Inflow 400 2859 350 300 2857 w 250 (cfs) 2855 200 Inflo 2853 150 Water Level (ft.) 100 2851 50

2849 0

5 6 6 6 6 05 0 0 0 06 005 0 006 00 006 00 0 2 /2 /20 2 /2 /20 2 2 /20 /2 4/ 5 6 6/ 0/ 1/ 2 1 /1 /1 1 19 /19 2 2 /21 /2 9/ 0 2 1/ 2/16/20063/ 4 5/ 6/20/20067/ 8 9/21/20060 1 11/15/20051 1

Date

Figure 4.27 – Piezometer 6 water level (ft) and Packwood Lake inflow (cfs).

46 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Piezometer 7(P-7)

A piezometer was installed approximately 20 ft horizontal distance from P-4 to further evaluate if a localized clay lens in the soil was responsible for differences in the water level response between P-3 and P-4. As previously described, there were indications that the construction of P- 4 had pierced a clay layer and resulted in that piezometer potentially monitoring a deeper aquifer. P-7 was installed on June 16, 2006 and constructed to a depth of 2.4 ft bgs, and in continuity with the shallow groundwater table associated with the wetland. There were no indications of a clay layer being pierced during the installation of P-7.

Water level data for P-7 were nearly identical to data from P-4 for the period that both piezometers were in operation. Figures 4-28 and 4-29 show the water level for P-7 relative to lake level and inflow, respectively. Water level for P7 was well correlated to lake level (R2 = 0.988). The water level dropped below the level logger elevation during 2006 drawdown before rapidly rising to above the ground surface during the large storm event at the beginning of November 2006. A physical examination of the soil condition during drawdown documented that the high clay content of the soil in this area resulted in the soil remaining fully saturated despite the lowered water table.

Packwood Lake Wetland Hydrology Piezometer 7 2863 2861 Lake Level Piezometer 7 2859 2857 2855 2853

Water Level (ft.) 2851 2849 6 6 6 05 0 0 0 06 0 0 0 0 0 /2005 2005 /2006 /2006 /2006 4 5/2005 9 0 1 1 /1 /2 /2 9/ 0/1 1/16/2 2/16/2006 3 4/19/2 5/20/2006 6 7/21/2006 8 9/21/2 1 11/15/2 12/16/ 10/22/2 Date

Figure 4.28 – Piezometer 7 water level (ft) and Packwood Lake level (ft).

47 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Packwood Lake Wetland Hydrology Piezometer 7

2863.00 500 Piezometer 7 Inflow 2861.00 450 400 ) 2859.00 350 2857.00 300 250 (cfs) 2855.00 200 Inflow 2853.00 150 Water Level (ft. 100 2851.00 50 0 2849.00 6 6 05 05 0 06 0 06 0 0 0 0 2 2 20 /2006 20 /2006 /2006 5/ 9 1 2 1 16/2005 /1 /2 2 9/14/2005 / 1/16/ 2/16/2 3/19/20064 5/20/ 6/20/2 7/21/20068/21/20069 0/ 10/ 11/15/ 12 1 Date

Figure 4.29 – Piezometer 7 water level (ft) and Packwood Lake inflow (cfs).

5.0 DISCUSSION

5.1 Drawdown Area

From May 1 to September 15, the Project operates with Project generation flow adjusted to match lake inflow to hold the lake elevation relatively constant. During the summer months, the Project’s generation is dictated by the FERC license lake level requirement of 2,857 feet MSL + 0.5 ft that corresponds to a range in surface area of 5.5 acres. Royce (1965) noted that U.S. Geological records for pre-Project years 1960 – 1963 reported a lake level fluctuation between May 1 and September 15 of approximately 1.2 to 2.1 feet. This corresponds to a change in surface area of the lake of 7 acres for the area between elevation 2857 ft MSL and 2855 ft MSL. The lake is then drawn down in the latter half of September prior to the annual Project shutdown for maintenance. Once the Project is shutdown (typically October 1), the lake level rises dependent upon natural inflow rates. If the lake is lowered to the minimum allowed elevation of 2,849.0 ft MSL at the beginning of the Project annual outage; this results in 34 acres being temporarily dewatered.

Table 5.1 lists the water elevation exceedance data for Packwood Lake. Monthly exceedance curves are provided in Appendix C. The 50% exceedance elevation is 2,857 ft +0.5 ft for May through September; lake elevation is at or above 2,856.5 ft 50% of the time in these months based on data from 1971 – 2006. The lake is at or above 2,857 ft 5.8% of the time in October and 13.25% of the time in November. The lake elevation exceeds 2,857 ft 8.3% of the time for December through April.

48 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Table 5.1 Percent Exceedance for Packwood Lake water elevation (1971 – 2006) Water Elevation (ft) Percent Exceedance Jan Feb Mar Apr May June 1% 2859.0 2859.9 2858.5 2858.7 2859.3 2859.4 10% 2856.6 2857.0 2856.3 2856.9 2857.8 2858.7 20% 2855.4 2855.4 2855.5 2856.5 2857.4 2858.0 30% 2854.8 2854.6 2855.1 2856.2 2857.2 2857.5 40% 2854.4 2854.1 2854.7 2855.9 2857.0 2857.2 50% 2854.0 2853.8 2854.3 2855.6 2856.9 2857.0 60% 2853.5 2853.4 2853.9 2855.4 2856.8 2856.9 70% 2853.1 2853.0 2853.5 2855.0 2856.6 2856.8 80% 2852.6 2852.5 2853.0 2854.2 2856.6 2856.7 90% 2852.1 2851.9 2852.2 2853.5 2856.4 2856.6 99% 2850.8 2850.2 2850.1 2852.4 2854.4 2856.2 Jly Aug Sept Oct Nov Dec 1% 2858.9 2858.2 2857.7 2859.0 2859.6 2859.6 10% 2857.7 2857.3 2857.1 2855.8 2857.7 2857.4 20% 2857.3 2857.2 2856.9 2854.5 2856.2 2855.7 30% 2857.1 2857.0 2856.8 2853.7 2855.7 2854.8 40% 2857.0 2857.0 2856.6 2853.0 2855.4 2854.4 50% 2856.9 2856.9 2856.5 2852.5 2854.9 2853.8 60% 2856.8 2856.8 2855.3 2852.0 2854.2 2853.3 70% 2856.7 2856.7 2854.0 2851.5 2853.7 2852.9 80% 2856.7 2856.7 2852.7 2851.0 2853.1 2852.5 90% 2856.6 2856.6 2851.3 2850.5 2852.5 2851.5 99% 2856.2 2856.3 2849.7 2849.4 2851.1 2850.6

The maximum drawdown rate was 5.1 acres/day in September 2005 and 4.6 acres/day in September 2006. The daily drawdown rate averaged 1 acre/day during the fall drawdown for both years. The maximum rate of decrease in lake area observed in other months during 2005 – 2006 ranged from 0.6 acres/day to 3.0 acres/day with average rates being approximately 0.0 to 0.3 acres/day. The rate of increases in lake area associated with inflow during flood events was as high as 24.4 acres/day. The rate of change that occurred during fall drawdown was similar to the rate of change on the descending limb of storm events as depicted in Figure 4.7

Potential impacts to fish and wildlife associated with the area of the lake affected by Project drawdown will be assessed in a synthesis report that Energy Northwest will distribute separately. The synthesis process will integrate results from multiple studies.

49 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Shoreline Erosion

Comparison of historic (1958) and recent (1992) aerial photographs and field observations of the drawdown zone and shoreline were made to assess erosion. No evidence of shoreline retreat was noted over the 34 year aerial photograph record except for the loss of one tree on the west side of Agnes Island. Areas of the drawdown zone that are armored with cobble/gravel substrate or bedrock (55% of area) have a low future erosion potential since the large substrate protects the shoreline from wave action and surface erosion during rainfall events. Fourteen percent of the drawdown area has sandy or gravel/sand substrate. These areas have a moderate future erosion potential. Three locations have a high future erosion/deposition potential; the stream deltas at the mouths of Lake/Mueller creeks, Osprey Creek, and the tributary north of Osprey Creek (31% of drawdown area). These areas are active deltas, and the streams deposit and then erode and re- work the delta deposits as the lake levels fluctuate.

Erosion of the lake shoreline during the term of the new license has the potential to affect cultural, riparian, recreation, and aquatic resources. The majority (69%) of the drawdown zone has a low or moderate erosion potential, and will have no or minimal effects on these resources. The sandy areas with a high erosion potential could result in exposure of any cultural artifacts close to the surface in those locations during the term of the new license. Project-related bank erosion (bank erosion at levels below 2857 ft MSL) does not appear to be occurring, so there do not appear to be any erosion effects on riparian or recreation resources. Non-Project bank erosion (bank erosion at 2857 ft MSL) is proceeding very slowly so these resources are not being affected very much by bank erosion). Bank erosion and trampling associated with recreation is occurring in a few locations. Erosion and shifting channels in the three delta areas could affect upstream fish passage if these areas are exposed during fish migration periods; however, studies to date indicate that upstream migration initiates no earlier than late May when the deltas are submerged with the lake at 2857 ft and outmigration appears to be completed in August prior to fall drawdown. Assessment of drawdown effects on fish migration were further assessed during synthesis.

5.2 Wetland Connectivity

Hydrology is critical to the structure and function of wetlands. Hydrology and timing can influence species composition and richness, primary productivity, accumulation of organic matter, and nutrient cycling in wetlands (Mitsch and Gosselink 1986). Therefore, understanding wetland hydrology is central to characterizing any potential effects of Project operations on wetlands and associated fish and wildlife.

Hypotheses were formulated specific to each wetland piezometer following a review of the first year of data. Data collected in summer 2006 provided a period during which lake level was maintained relatively constant but inflow showed a gradually decreasing trend. If upslope hydrology was the primary determinant of wetland groundwater level, then it was hypothesized that the latter would be expected to gradually decrease through the summer and be relatively unaffected by the fall drawdown. The alternative hypothesis was that groundwater level would remain fairly constant during the summer followed by a decrease in the fall if lake level was the primary determinant.

50 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

The two large wetland complexes adjacent to Packwood Lake showed very different responses to drawdown. The wetland complex adjacent to Osprey Creek includes both palustrine emergent seasonally flooded and palustrine forested wetlands dominated by red alder. Other tree species in this wetland include mountain hemlock and red cedar. There is abundant downed large woody debris. The soils in this wetland are saturated near the surface nearly year round. The upslope hydrology was the primary determinant of groundwater hydrology for this wetland complex. Water level within the piezometers was unresponsive to lake level drawdowns. Shallow groundwater hydrology supporting wetlands adjacent to Osprey Creek was very stable throughout the monitoring period. Water levels in P-5 remained stable, in spite of significant changes in lake level and inflow. Water levels in P-6 also were stable throughout a majority of the monitoring period.

The wetland complex at the upper end of the lake was mapped as a palustrine forested wetland with areas dominated by red alder as well as mixed tree stands (DTA 2006). Red alders were dominant with typical trunk diameter being 10-14 in dbh. Downed large woody debris was abundant. Upper Lake Creek and Muller Creek flow through this wetland complex. The near- shore area of this wetland complex exhibited complex hydrologic functions. Low lying areas, as best represented by P-2 are seasonally flooded much of the year. The water table at slightly higher ground elevations that occur on hummocks (similar to P-3) was within the upper 18 inches of soil but only sporadically saturated to the surface.

The portion of this wetland near Muller Creek was mapped as a mixed stand palustrine forested wetland. Piezometers P-1 and P-2 were located in this part of the wetland. The groundwater level at both of these piezometers was primarily a function of lake level during the drier portion of the year (July through October). Precipitation and upslope hydrology (inflow) were the primarily determinants of groundwater level during the rest of the year. The transition was abrupt in both 2005 and 2006 with the onset of the first large fall storm events in October – November.

The fall drawdown had the effect of lowering the groundwater level 1.0 ft to 1.3 ft, which was at a level more than 18 inches below the ground surface. This magnitude of change was muted relative to a lake level change of approximately 7.5 ft. The water table and ground level was at a higher elevation at P-1 than P-2 with the slope towards the lake; however the relative magnitude of the effects of lake drawdown on wetland water elevation were very similar.

The groundwater level at P-3, which is closer to Lake Creek, was not closely associated with lake level. The gradual decline in water level at P-3 during the summer months suggests that the hydrology for the wetland in this vicinity of this piezometer was primarily a function of upslope hydrology or inflow. The water level at P-3 dropped about 0.6 ft during the fall 2006 drawdown; however, this rate of decline was similar to rates observed earlier in the summer (Figure 5-1). The minimum elevation for the water table at P-2 was very similar to the level at P-3 for the fall 2006 drawdown, which suggests that the lake level may define the minimum water table elevation throughout the near shore area of this wetland. The lake level likely had some influence on wetland hydrology during the drawdown but the effect was partially masked by the greater influence of upslope hydrology.

51 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

Packwood Lake Wetland Hydrology

2863 200

Lake Level P-1 P-2 P-3 P-4 Inflow 180 2861 160

2859 140 120 2857 100 2855

(ft.)MSL 80 Inflow (cfs)

Water Level 2853 60 40 2851 20 2849 0 6 06 06 06 06 06 0 006 006 006 0 006 /2 2 /2 /20 5/2 2/2006 9/200 2/2006 9/2 6/2006 3/2006 0/2 7/1/20067/8 8/5/2006 9/2/20 9/9 7/1 7/2 7/2 8/1 8/1 8/26/ 9/1 9/2 9/3 10/7/2006 10/14/200610/21 10/28/20 Date

Figure 5-1 – Water level for Piezometers at the upper end of Packwood Lake Level for summer/fall 2006

Piezometer P-3 was located approximately 200 ft from the lake shoreline. Piezometers P-4 and P-7 were located approximately 60 ft from the shoreline. While the summer/fall groundwater table at P-3 was primarily a function of upslope hydrology, the groundwater hydrology was strongly controlled by lake level for the near shore environment adjacent to Lake Creek as represented by P-4 and P-7. There was no obvious transition in vegetation between the locations of these piezometers. This portion of the wetland was mapped as a red-alder dominated palustrine forested wetland. The canopy matrix was red alder with 70% - 90% canopy coverage (DTA 2006). Abundant downed wood was present. According to DTA (2006), shrub cover was dominated by red elderberry (Sambucus racemosa) and vine maple (Acer circinatum). Herbaceous species found were diverse and included lady fern (Athyrium filix-femina), skunk cabbage (Lysichitum americanum), cow-parsnip (Heracleum lanatum), Cooley’s hedge-nettle (Stachys cooleyae), mitrewort (Mitella sp.), piggy-back plant (Tolmiea menziesii), forget-me-not (Myosotis laxa), and monkey-flower (Mimulus sp.).

The soil near P-4 and P-7 was characterized as clay overlaying sandy clay. The soil profile was heavily gleyed, which is indicative of seasonal saturation for extended periods. A clay lens was perforated when P-4 was installed. A second piezometer (P-7) installed nearby at a slightly shallower position in the soil did not perforate the clay lens. Both piezometers reported nearly identical trends for water level, which indicated that the installation of P-4 did not bias results. Although the water table at this location dropped to a level several feet below the ground surface, the surface soils remained saturated due to their high clay content.

52 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

The effect of lake drawdown on the hydrology of the wetland complex at the upper end of the lake was most pronounced in the vicinity of P-4. The lake level had very little effect on wetland hydrology at a point approximately 200 ft from the shoreline for the eastern portion (closer to P- 3). The soil hydrology of the portion of this wetland closer to Muller Creek was a function of lake level during the drier months (July - October) and a function of upslope hydrology during wetter months. Even in areas where the water table dropped below the typical vegetation root zone of 18 inches (Brinson 1993), the high clay content of the soil kept it at or near saturation.

There is only very limited information on seasonal lake level fluctuations prior to construction of the project. Maintaining the lake level at 2857 +0.5 ft may have the effect of maintaining a slightly higher groundwater table within the nearshore portion of the wetland complex at the head of Packwood Lake during late summer. The linear trend for summer groundwater elevation at P-3 is shown in Figure 5-1. The groundwater level reached an equilibrium elevation relative to lake level by mid-August and remained at that elevation until drawdown. The level then dropped to a level comparable to the elevation that was likely, had the seasonal trend continued. The USFS (February 12, 1961) noted that the outlet of Packwood Lake was characterized by an alluvial deposit with continuous seepage flows of 10-15 cfs. Royce (1965): notes “The changes in lake level recorded by the U.S. Geological survey through the years ’60 through ’63 show differences between annual maxima and minima ranging from 2.3 to 3.4 feet. The summer changes in lake level between May 1 and September 15 during these same years ranged from approximately 1.2 to 2.1 feet.”…..“I would judge from the shoreline development that the seasonal average in lake level must have been in the neighborhood of 2856 to 2857 feet, as measured by the most recent surveys.” Figure 5-2 shows Packwood Lake in August 1937; the water level near the intake appears very similar to summer water elevations today.

53 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

The minimum ground water elevation during the Project lake drawdown for most of the wetland complex at the upper end of Packwood Lake may be similar to and probably not more than the groundwater level for pre-project conditions if the summer lake level fluctuation was in the range reported by Royce. The duration of the drawdown effect is limited to 2-4 weeks in September and October with the wetlands being quickly recharged with the onset of fall precipitation. The water level in the wetlands remains at or near the surface during the winter months with minimal influence from lake level; i.e., upslope hydrology is dominant during the winter and spring.

Figure 5-2 – Anglers at Packwood Lake near the intake, photograph by Ray M. Fillon, August 29, 1937 (Courtesy of USDA forest Service).

The biological consequences of lake level drawdown potentially affect aquatic biota in the lake as well as biota within the wetlands adjacent to the lake. Energy Northwest prepared and distributed a synthesis that assesses the hydrological effects of drawdown relative to biological effects.

54 Final Report Packwood Lake Drawdown Study Energy Northwest Packwood Lake Hydroelectric Project July 2007 FERC No. 2244

6.0 LITERATURE CITED

Brinson, M.M. 1993. A Hydrogeomorphic Classification for Wetlands. Wetland Research Program Technical Report WRP-DE-4. U.S. Army Engineer Waterways Experiment Station, Vicksburg, Mississippi.

Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deepwater habitats of the United States. FWS2/OBS-79/31, US Fish and Wildlife Service Office of Biological Services, Washington D.C.

Devine Tarbell and Associates. 2006. Draft Vegetation Cover Type Mapping Study for Packwood Lake Hydroelectric Project, FERC No. 2244, Lewis County, Washington. November 2006.

EES Consulting. 2005. Revised Packwood Lake Drawdown Study Plan for Energy Northwest’s Packwood Lake Hydroelectric Project, FERC No. 2244, Lewis County, Washington. Submitted to Energy Northwest, Richland, WA by EES Consulting and Watershed GeoDynamics. August 22, 2005.

Energy Northwest. 2004. Pre-Application Document, Supplement No. 1 and Notice of Intent. December 6, 2004. Richland WA.

Finlayson, D.P., 2006. The Geomorphology of Puget Sound Beaches. Ph.D. Dissertation, University of Washington, Seattle, WA. 216pp. Available at http://david.p.finlayson.googlepages.com/pugetsoundbeaches

Mitsch, W.J. and J.G. Gosselink. 1986. Wetlands. Van Nostrand Reinhold Company, New York 539 pp.

Royce, William F. 1965. “Effect of changes in lake level on fishing in Packwood Lake”. University of Washington, Seattle,.

Sherwood, C., 2006. Demonstration Sediment-Transport Applets. Available at: http://woodshole.er.usgs.gov/staffpages/csherwood/sedx_equations/sedxinfo.html

USDA Forest Service. USFS. 1961. Letter from Forestry Service to Joseph C. Swidler, FERC dated February 12, 1961.

USDA Forest Service. USFS 2005. Comments on PAD and Scoping Document 1 and Study Requests Packwood Lake Project No. 2244-012. March 11, 2005.

Washington Department of Fish and Wildlife. WDFW. 2005. Packwood Lake Hydroelectric Project, FERC No. P-2244-012 Comments on the Pre-Application Document, Study Requests, and Comments on Scoping Document 1. March 9, 2005.

55

APPENDIX A Piezometer Images

Piezometer 1 – April 19, 2006 Adjacent Muller Creek (off-lake)

Piezometer 2 – November 9, 2005 Adjacent Muller Creek (near lake)

Piezometer 3 – November 9, 2005 Adjacent Lake Creek (off-lake)

Piezometer 4 – April 19, 2006 Adjacent Lake Creek (nearest lake)

Piezometer 5 – November 9, 2005 Adjacent Osprey Creek (off-lake)

Piezometer 6 – April 19, 2006 Adjacent Osprey Creek (nearest lake)

Piezometer 7 Photo not available

Appendix B Packwood Lake Elevation and Inflow Water Years 2001 – 2006

1999-2000 2860 600

2858 500

Full Pool

2856 400

2854 300 Inflow (cfs)

Reservoir level (ft. MSL) level (ft. Reservoir 2852 200

2850 100 Max. Drawdown

2848 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Date

Lake Level Total Inflow Inflow >200 cfs + Lake < 2857 2000-2001 2860 600

2858 500

Full Pool

2856 400

2854 300 Inflow (cfs)

Reservoir level (ft. MSL) level (ft. Reservoir 2852 200

2850 100 Max. Drawdown

2848 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Date

Lake Level Total Inflow Inflow >200 cfs + Lake < 2857 2001-2002 2860 600

2858 500

Full Pool

2856 400

2854 300 Inflow (cfs)

Reservoir level (ft. MSL) level (ft. Reservoir 2852 200

2850 100 Max. Drawdown

2848 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Date

Lake Level Total Inflow Inflow >200 cfs + Lake < 2857 2002-2003 2860 600

2858 500

Full Pool

2856 400

2854 300 Inflow (cfs)

Reservoir level (ft. MSL) level (ft. Reservoir 2852 200

2850 100 Max. Drawdown

2848 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Date

Lake Level Total Inflow Inflow >200 cfs + Lake < 2857 2003-2004 2860 600

2858 500

Full Pool

2856 400

2854 300 Inflow (cfs)

Reservoir level (ft. MSL) level (ft. Reservoir 2852 200

2850 100 Max. Drawdown

2848 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Date

Lake Level Total Inflow Inflow >200 cfs + Lake < 2857 2004-2005 2860 600

2858 500

Full Pool

2856 400

2854 300 Inflow (cfs)

Reservoir level (ft. MSL) level (ft. Reservoir 2852 200

2850 100 Max. Drawdown

2848 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Date

Lake Level Total Inflow Inflow >200 cfs + Lake < 2857 2005-2006 2860 600

2858 500

Full Pool

2856 400

2854 300 Inflow (cfs)

Reservoir level (ft. MSL) level (ft. Reservoir 2852 200

2850 100 Max.

2848 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Date

Lake Level Total Inflow Inflow >200 cfs + Lake < 2857

Appendix C Lake Elevation Exceedance Curves

Elevation Duration Curve, 1971 - 2006

2,860 2,859 January 2,858 2,857 2,856 2,855 2,854 (ft) 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 February 2,858 2,857 2,856 2,855 2,854 (ft) 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 March 2,858 2,857 2,856 2,855 2,854 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation (ft) 2,848 0 102030405060708090100 Percent Exceedence Elevation Duration Curve, 1971 - 2006

2,860 2,859 April 2,858 2,857 2,856 2,855 2,854 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation (ft) 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 May 2,858 2,857 2,856 2,855 2,854 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation (ft) 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 June 2,858 2,857 2,856 2,855 2,854 2,853 2,852 Elevation (ft) 2,851 2,850 Packwood Lake Water 2,849 2,848 0 102030405060708090100 Percent Exceedence Elevation Duration Curve, 1971 - 2006

2,860 2,859 July 2,858 2,857 2,856 2,855 2,854 (ft) 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 August 2,858 2,857 2,856 2,855 2,854 (ft) 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 September 2,858 2,857 2,856 2,855 2,854 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation (ft) 2,848 0 102030405060708090100 Percent Exceedence Elevation Duration Curve, 1971 - 2006

2,860 2,859 October 2,858 2,857 2,856 2,855 2,854 (ft) 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 November 2,858 2,857 2,856 2,855 2,854 (ft) 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation 2,848 0 102030405060708090100 Percent Exceedence

Elevation Duration Curve, 1971 - 2006

2,860 2,859 December 2,858 2,857 2,856 2,855 2,854 2,853 2,852 2,851 2,850 2,849

Packwood Lake Water Elevation (ft) 2,848 0 102030405060708090100 Percent Exceedence

Appendix D Semi Quantified Wetland Assessment Forms

FIELD FORM FOR HYDROLOGY AND SOIL DESCRIPTIONS

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____1______Crew:______Date:_8/31/2006_____

County: Lewis Orthophoto #:______CLASS SUBCLASS

HGM Riverine: Palustrine Flow-through Classification: Depressional: Outflow to lake subsurface and seasonal surface during floods Slope: low gradient Alluvial floodplain: Flats: OTHER GENERAL HYDROLOGY INFORMATION:

Field Observations: Depth of Surface Water: _0 (in.) Depth to Free Water in Pit:___12__ (in.) Depth to Saturated Soil:____6_____ (in.)

Wetland Hydrology Indicators: ____Inundated __X__Saturated in upper 12 inches __X__Water Marks _X___ Drift Lines ____Sediment Deposits __X__ Drainage Patterns __X__Redoximorhpic Features _X___ Water Stained Leaves _X___ Other (describe)

Evidence of inundation, water level fluctuation, maximum depth, etc. (describe) Soil profile indicates prolonged inundation due to high organic muck content; surface tension cracks on soil.

Inlet: No Yes (Describe) seasonal surface flow occurs during extreme high water level in lake and during winter through spring

Outlet: No Yes (Describe) minor expression of surface drainages that are seasonally inudated

Hydrologic Source/Control (describe): upslope hydrology and precipitation during approx. late Oct – June. Lake level affects hydrology during dry summer months.

SOILS INFORMATION:

Profile Description: Matrix Color Mottle Colors Depth Mottle Horizon (Munsell (Munsell Texture/Concretions/Rhizospheres, etc. (inches) Abundance/Contrast Moist) Moist) 0-2 A 10YR2.2 no Organic muck 2-24 A-B 10YR2.2 no Organic muck 24-28 C 10YR2.1 Silt loam

FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:__1______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Flood/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Storm Water __ riverine or lakeshore wetland __ mid-sloped wetland _X_ depressions, headwaters, bogs, flats __ <10% forested cover __ 10 – 30% forested cover X__ > 30% forested cover Control __ unconstrained outlet __ semi-constrained outlet __ culvert/bermed outlet __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage

Base Flow/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Ground Water __ riverine or lakeshore wetland __ mid-sloped wetland X__ depressions, headwaters, bogs, flats __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage Support __ temporarily flooded or saturated __ seasonally or semi-permanently __ permanently flooded or saturated, or Flooded or saturated intermittently exposed __ no flow-sensitive fish populations __ low flow-sensitive fish populations on-site or downstream on-site or downstream

Erosion/ __ spare grass/herbs or no veg along __ sparse wood or veg along OHWM __ dense wood or veg along OHWM Shoreline OHWM __ wetland extends < 30 m from OHWM __ wetland extends 30-60 m from OHWM X__ wetland extends > 200 m from Protection OHWM

Water Quality __ rapid flow through site __ moderate flow through site X__ slow flow through site Improvement __ <50% veg cover __ 50-80 % cover X__ >80% veg cover __ holds <25% overland runoff __ holds 25-50 % overland runoff __ holds > 50 % overland runoff __ soil is coarse gravel, sand, or sandy __ soil is organic mineral mix X__ soil is heavy organic muck and peat Loam

N/A = Not Applicable N/I = No information available FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____1______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Natural __ size <5 acres __ size 5-10 acres X__ size > 10 acres Biological Support __ low veg structure __ 2 level veg X__ high veg structure __ seasonal surface water __ permanent surface water __ open water pools through summer __ one habitat type __ two habitat types X__ > 3 habitat types PAB POW PEM PSS PFO EST __ PAB POW PEM PSS PFO EST _X_ PAB POW PEM PSS PFO EST __ low plant diversity (< 6 species) __ moderate plant diversity __ high plant diversity __ (7-15 species) __ (>15 species) __ > 50% invasive species __ 10 to 50% invasive species _X_ <10% invasive species __ low primary productivity __ moderate primary productivity __ high primary productivity __ low organic accumulation __ moderate organic accumulation X__ high organic accumulation __ low organic export __ low organic export __ high organic export __ few habitat features __ some habitat features _X_ many habitat features __ isolated from upland habitats __ partially connected to upland __ well connected to upland habitats habitats

Overall __ size <5 acres __ size 5-10 acres _X_ size > 10 acres Habitat __ low habitat diversity __ moderate habitat diversity _X_ high habitat diversity __ low sanctuary or refuge __ moderate sanctuary or refuge X__ high sanctuary or refuge Functions

Specific __ low invertebrate habitat __ moderate invertebrate habitat __ high invertebrate habitat Habitat Functions __ low amphibian habitat __ moderate amphibian habitat X__ high amphibian habitat __ low fish habitat __ moderate fish habitat __ high fish habitat __ low mammal habitat __ moderate mammal habitat _X_ high mammal habitat __ low bird habitat __ moderate bird habitat moderate _X_ high bird habitat

Cultural/ __ low educational opportunities __ moderate educational opportunities X__ high educational opportunities Socioeconomic __ low aesthetic value __ moderate aesthetic value _X_ high aesthetic value __ lacks passive and active __ some passive and active __ many passive and active recreational opportunities recreational opportunities recreational opportunities

Notes: FIELD FORM FOR HYDROLOGY AND SOIL DESCRIPTIONS

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____2______Crew:______Date:_8/31/2006_____

County: Lewis Orthophoto #:______CLASS SUBCLASS

HGM Riverine: Palustrine Flow-through Classification: Depressional: Outflow Slope: Low gradient alluvial Flats: OTHER GENERAL HYDROLOGY INFORMATION:

Field Observations: Depth of Surface Water: _0 (in.) Depth to Free Water in Pit:___1.3__ (in.) Depth to Saturated Soil:____1_____ (in.)

Wetland Hydrology Indicators: ____Inundated __X__Saturated in upper 12 inches __X__Water Marks _X___ Drift Lines ____Sediment Deposits __X__ Drainage Patterns __X__Redoximorhpic Features _X___ Water Stained Leaves _X___ Other (describe)

Evidence of inundation, water level fluctuation, maximum depth, etc. (describe) Soil profile indicates prolonged inundation due to high organic muck content; surface tension cracks on soil.

Inlet: No Yes (Describe) seasonal surface flow occurs during extreme high water level in lake and during winter through spring

Outlet: No Yes (Describe) minor expression of surface drainages that are seasonally inudated

Hydrologic Source/Control (describe): upslope hydrology and precipitation during approx. late Oct – June. Lake level affects hydrology during dry summer months.

SOILS INFORMATION:

Profile Description: Matrix Color Mottle Colors Depth Mottle Horizon (Munsell (Munsell Texture/Concretions/Rhizospheres, etc. (inches) Abundance/Contrast Moist) Moist) 0-2 A 10YR2.2 no Organic muck 2-24 A-B 10YR2.2 no Organic muck 24-28 C 10YR2.1 Silt loam

FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:__2______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Flood/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Storm Water __ riverine or lakeshore wetland __ mid-sloped wetland _X_ depressions, headwaters, bogs, flats __ <10% forested cover __ 10 – 30% forested cover X__ > 30% forested cover Control __ unconstrained outlet __ semi-constrained outlet __ culvert/bermed outlet __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage

Base Flow/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Ground Water __ riverine or lakeshore wetland __ mid-sloped wetland X__ depressions, headwaters, bogs, flats __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage Support __ temporarily flooded or saturated __ seasonally or semi-permanently __ permanently flooded or saturated, or Flooded or saturated intermittently exposed __ no flow-sensitive fish populations __ low flow-sensitive fish populations on-site or downstream on-site or downstream

Erosion/ __ spare grass/herbs or no veg along __ sparse wood or veg along OHWM __ dense wood or veg along OHWM Shoreline OHWM __ wetland extends < 30 m from OHWM __ wetland extends 30-60 m from OHWM X__ wetland extends > 200 m from Protection OHWM

Water Quality __ rapid flow through site __ moderate flow through site X__ slow flow through site Improvement __ <50% veg cover __ 50-80 % cover X__ >80% veg cover __ holds <25% overland runoff __ holds 25-50 % overland runoff __ holds > 50 % overland runoff __ soil is coarse gravel, sand, or sandy __ soil is organic mineral mix X__ soil is heavy organic muck and peat Loam

N/A = Not Applicable N/I = No information available FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____2______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Natural __ size <5 acres __ size 5-10 acres X__ size > 10 acres Biological Support __ low veg structure __ 2 level veg X__ high veg structure __ seasonal surface water __ permanent surface water __ open water pools through summer __ one habitat type __ two habitat types X__ > 3 habitat types PAB POW PEM PSS PFO EST __ PAB POW PEM PSS PFO EST _X_ PAB POW PEM PSS PFO EST __ low plant diversity (< 6 species) __ moderate plant diversity __ high plant diversity __ (7-15 species) __ (>15 species) __ > 50% invasive species __ 10 to 50% invasive species _X_ <10% invasive species __ low primary productivity __ moderate primary productivity __ high primary productivity __ low organic accumulation __ moderate organic accumulation X__ high organic accumulation __ low organic export __ low organic export __ high organic export __ few habitat features __ some habitat features _X_ many habitat features __ isolated from upland habitats __ partially connected to upland __ well connected to upland habitats habitats

Overall __ size <5 acres __ size 5-10 acres _X_ size > 10 acres Habitat __ low habitat diversity __ moderate habitat diversity _X_ high habitat diversity __ low sanctuary or refuge __ moderate sanctuary or refuge X__ high sanctuary or refuge Functions

Specific __ low invertebrate habitat __ moderate invertebrate habitat __ high invertebrate habitat Habitat Functions __ low amphibian habitat __ moderate amphibian habitat X__ high amphibian habitat __ low fish habitat __ moderate fish habitat __ high fish habitat __ low mammal habitat __ moderate mammal habitat _X_ high mammal habitat __ low bird habitat __ moderate bird habitat moderate _X_ high bird habitat

Cultural/ __ low educational opportunities __ moderate educational opportunities X__ high educational opportunities Socioeconomic __ low aesthetic value __ moderate aesthetic value _X_ high aesthetic value __ lacks passive and active __ some passive and active __ many passive and active recreational opportunities recreational opportunities recreational opportunities

Notes: FIELD FORM FOR HYDROLOGY AND SOIL DESCRIPTIONS

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____3______Crew:______Date:_8/31/2006_____

County: Lewis Orthophoto #:______CLASS SUBCLASS

HGM Riverine: Palustrine Flow-through Classification: Depressional: Outflow Slope: Low gradient Alluvial floodplain Flats: OTHER GENERAL HYDROLOGY INFORMATION:

Field Observations: Depth of Surface Water: _0 (in.) Depth to Free Water in Pit:___36__ (in.) Depth to Saturated Soil:____27_____ (in.)

Wetland Hydrology Indicators: ____Inundated ____Saturated in upper 12 inches __X__Water Marks _X___ Drift Lines ____Sediment Deposits __X__ Drainage Patterns __X__Redoximorhpic Features _X___ Water Stained Leaves _X___ Other (describe)

Evidence of inundation, water level fluctuation, maximum depth, etc. (describe) Soil profile indicates prolonged inundation due to high organic muck content; surface tension cracks on soil.

Inlet: No Yes (Describe) seasonal surface flow occurs during extreme high water level in lake and during winter through spring

Outlet: No Yes (Describe) minor expression of surface drainages that are seasonally inudated

Hydrologic Source/Control (describe): upslope hydrology and precipitation during approx. late Oct – June. Lake level affects hydrology during dry summer months.

SOILS INFORMATION:

Profile Description: Matrix Color Mottle Colors Depth Mottle Horizon (Munsell (Munsell Texture/Concretions/Rhizospheres, etc. (inches) Abundance/Contrast Moist) Moist) 0-22 A 10YR3.2 no Clay sand >23 A-B gley no sandy

FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:__3______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Flood/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Storm Water __ riverine or lakeshore wetland __ mid-sloped wetland _X_ depressions, headwaters, bogs, flats __ <10% forested cover __ 10 – 30% forested cover X__ > 30% forested cover Control __ unconstrained outlet __ semi-constrained outlet __ culvert/bermed outlet __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage

Base Flow/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Ground Water __ riverine or lakeshore wetland __ mid-sloped wetland X__ depressions, headwaters, bogs, flats __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage Support __ temporarily flooded or saturated __ seasonally or semi-permanently __ permanently flooded or saturated, or Flooded or saturated intermittently exposed __ no flow-sensitive fish populations __ low flow-sensitive fish populations on-site or downstream on-site or downstream

Erosion/ __ spare grass/herbs or no veg along __ sparse wood or veg along OHWM __ dense wood or veg along OHWM Shoreline OHWM __ wetland extends < 30 m from OHWM __ wetland extends 30-60 m from OHWM X__ wetland extends > 200 m from Protection OHWM

Water Quality __ rapid flow through site __ moderate flow through site X__ slow flow through site Improvement __ <50% veg cover __ 50-80 % cover X__ >80% veg cover __ holds <25% overland runoff __ holds 25-50 % overland runoff __ holds > 50 % overland runoff __ soil is coarse gravel, sand, or sandy __ soil is organic mineral mix X__ soil is heavy organic muck and peat Loam

N/A = Not Applicable N/I = No information available FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____3______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Natural __ size <5 acres __ size 5-10 acres X__ size > 10 acres Biological Support __ low veg structure __ 2 level veg X__ high veg structure __ seasonal surface water __ permanent surface water __ open water pools through summer __ one habitat type __ two habitat types X__ > 3 habitat types PAB POW PEM PSS PFO EST __ PAB POW PEM PSS PFO EST _X_ PAB POW PEM PSS PFO EST __ low plant diversity (< 6 species) __ moderate plant diversity __ high plant diversity __ (7-15 species) __ (>15 species) __ > 50% invasive species __ 10 to 50% invasive species _X_ <10% invasive species __ low primary productivity __ moderate primary productivity __ high primary productivity __ low organic accumulation __ moderate organic accumulation __ high organic accumulation __ low organic export __ low organic export __ high organic export __ few habitat features __ some habitat features _X_ many habitat features __ isolated from upland habitats __ partially connected to upland __ well connected to upland habitats habitats

Overall __ size <5 acres __ size 5-10 acres _X_ size > 10 acres Habitat __ low habitat diversity __ moderate habitat diversity _X_ high habitat diversity __ low sanctuary or refuge __ moderate sanctuary or refuge X__ high sanctuary or refuge Functions

Specific __ low invertebrate habitat __ moderate invertebrate habitat __ high invertebrate habitat Habitat Functions __ low amphibian habitat __ moderate amphibian habitat X__ high amphibian habitat __ low fish habitat __ moderate fish habitat __ high fish habitat __ low mammal habitat __ moderate mammal habitat _X_ high mammal habitat __ low bird habitat __ moderate bird habitat moderate _X_ high bird habitat

Cultural/ __ low educational opportunities __ moderate educational opportunities X__ high educational opportunities Socioeconomic __ low aesthetic value __ moderate aesthetic value _X_ high aesthetic value __ lacks passive and active __ some passive and active __ many passive and active recreational opportunities recreational opportunities recreational opportunities

Notes: FIELD FORM FOR HYDROLOGY AND SOIL DESCRIPTIONS

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____4______Crew:______Date:_8/31/2006_____

County: Lewis Orthophoto #:______CLASS SUBCLASS

HGM Riverine: Palustrine Flow-through Classification: Depressional: Outflow Slope: Low gradient Alluvial/Lacustrine Fringe: Flats: OTHER GENERAL HYDROLOGY INFORMATION:

Field Observations: Depth of Surface Water: _0 (in.) Depth to Free Water in Pit:___26__ (in.) Depth to Saturated Soil:____5_____ (in.)

Wetland Hydrology Indicators: ____Inundated __X__Saturated in upper 12 inches __X__Water Marks _X___ Drift Lines ____Sediment Deposits __X__ Drainage Patterns __X__Redoximorhpic Features _X___ Water Stained Leaves _X___ Other (describe)

Evidence of inundation, water level fluctuation, maximum depth, etc. (describe) Soil profile indicates prolonged inundation due to high organic muck content; surface tension cracks on soil.

Inlet: No Yes (Describe) seasonal surface flow occurs during extreme high water level in lake and during winter through spring

Outlet: No Yes (Describe) minor expression of surface drainages that are seasonally inudated

Hydrologic Source/Control (describe): upslope hydrology and precipitation during approx. late Oct – June. Lake level affects hydrology during dry summer months.

SOILS INFORMATION:

Profile Description: Matrix Color Mottle Colors Depth Mottle Hborizon (Munsell (Munsell Texture/Concretions/Rhizospheres, etc. (inches) Abundance/Contrast Moist) Moist) 0-25 A_B 310Y gley no Silty clay 26 C gley abundant clay

FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:__4______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Flood/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Storm Water __ riverine or lakeshore wetland __ mid-sloped wetland _X_ depressions, headwaters, bogs, flats __ <10% forested cover __ 10 – 30% forested cover X__ > 30% forested cover Control __ unconstrained outlet __ semi-constrained outlet __ culvert/bermed outlet __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage

Base Flow/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Ground Water __ riverine or lakeshore wetland __ mid-sloped wetland X__ depressions, headwaters, bogs, flats __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage Support __ temporarily flooded or saturated __ seasonally or semi-permanently __ permanently flooded or saturated, or Flooded or saturated intermittently exposed __ no flow-sensitive fish populations __ low flow-sensitive fish populations on-site or downstream on-site or downstream

Erosion/ __ spare grass/herbs or no veg along __ sparse wood or veg along OHWM __ dense wood or veg along OHWM Shoreline OHWM __ wetland extends < 30 m from OHWM __ wetland extends 30-60 m from OHWM X__ wetland extends > 200 m from Protection OHWM

Water Quality __ rapid flow through site __ moderate flow through site X__ slow flow through site Improvement __ <50% veg cover __ 50-80 % cover X__ >80% veg cover __ holds <25% overland runoff __ holds 25-50 % overland runoff __ holds > 50 % overland runoff __ soil is coarse gravel, sand, or sandy __ soil is organic mineral mix __ soil is heavy organic muck and peat Loam

N/A = Not Applicable N/I = No information available FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____4______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Natural __ size <5 acres __ size 5-10 acres X__ size > 10 acres Biological Support __ low veg structure __ 2 level veg X__ high veg structure __ seasonal surface water __ permanent surface water __ open water pools through summer __ one habitat type __ two habitat types X__ > 3 habitat types PAB POW PEM PSS PFO EST __ PAB POW PEM PSS PFO EST _X_ PAB POW PEM PSS PFO EST __ low plant diversity (< 6 species) __ moderate plant diversity __ high plant diversity __ (7-15 species) __ (>15 species) __ > 50% invasive species __ 10 to 50% invasive species __ <10% invasive species __ low primary productivity __ moderate primary productivity __ high primary productivity __ low organic accumulation __ moderate organic accumulation X__ high organic accumulation __ low organic export __ low organic export __ high organic export __ few habitat features __ some habitat features _X_ many habitat features __ isolated from upland habitats __ partially connected to upland __ well connected to upland habitats habitats

Overall __ size <5 acres __ size 5-10 acres _X_ size > 10 acres Habitat __ low habitat diversity __ moderate habitat diversity _X_ high habitat diversity __ low sanctuary or refuge __ moderate sanctuary or refuge X__ high sanctuary or refuge Functions

Specific __ low invertebrate habitat __ moderate invertebrate habitat __ high invertebrate habitat Habitat Functions __ low amphibian habitat __ moderate amphibian habitat X__ high amphibian habitat __ low fish habitat __ moderate fish habitat __ high fish habitat __ low mammal habitat __ moderate mammal habitat _X_ high mammal habitat __ low bird habitat __ moderate bird habitat moderate _X_ high bird habitat

Cultural/ __ low educational opportunities __ moderate educational opportunities X__ high educational opportunities Socioeconomic __ low aesthetic value __ moderate aesthetic value _X_ high aesthetic value __ lacks passive and active __ some passive and active __ many passive and active recreational opportunities recreational opportunities recreational opportunities

Notes: FIELD FORM FOR HYDROLOGY AND SOIL DESCRIPTIONS

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____5______Crew:______Date:_8/31/2006_____

County: Lewis Orthophoto #:______CLASS SUBCLASS

HGM Riverine: Palustrine Flow-through Classification: Depressional: Outflow Slope: low Alluvial floodplain Flats: OTHER GENERAL HYDROLOGY INFORMATION:

Field Observations: Depth of Surface Water: _0 (in.) Depth to Free Water in Pit:___7__ (in.) Depth to Saturated Soil:____0_____ (in.)

Wetland Hydrology Indicators: ____Inundated __X__Saturated in upper 12 inches __X__Water Marks _X___ Drift Lines ____Sediment Deposits __X__ Drainage Patterns __X__Redoximorhpic Features _X___ Water Stained Leaves _X___ Other (describe)

Evidence of inundation, water level fluctuation, maximum depth, etc. (describe) Soil profile indicates prolonged inundation due to high organic muck content; surface tension cracks on soil.

Inlet: No Yes (Describe) seasonal surface flow occurs during extreme high water level in lake and during winter through spring

Outlet: No Yes (Describe) minor expression of surface drainages that are seasonally inudated

Hydrologic Source/Control (describe): upslope hydrology and precipitation during approx. late Oct – June. Lake level affects hydrology during dry summer months.

SOILS INFORMATION:

Profile Description: Matrix Color Mottle Colors Depth Mottle Horizon (Munsell (Munsell Texture/Concretions/Rhizospheres, etc. (inches) Abundance/Contrast Moist) Moist) 0-26 A 10YR2.2 no Organic muck muck

FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:__5______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Flood/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Storm Water __ riverine or lakeshore wetland __ mid-sloped wetland _X_ depressions, headwaters, bogs, flats __ <10% forested cover __ 10 – 30% forested cover X__ > 30% forested cover Control __ unconstrained outlet __ semi-constrained outlet __ culvert/bermed outlet __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage

Base Flow/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Ground Water __ riverine or lakeshore wetland __ mid-sloped wetland X__ depressions, headwaters, bogs, flats __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage Support __ temporarily flooded or saturated __ seasonally or semi-permanently __ permanently flooded or saturated, or Flooded or saturated intermittently exposed __ no flow-sensitive fish populations __ low flow-sensitive fish populations on-site or downstream on-site or downstream

Erosion/ __ spare grass/herbs or no veg along __ sparse wood or veg along OHWM __ dense wood or veg along OHWM Shoreline OHWM __ wetland extends < 30 m from OHWM __ wetland extends 30-60 m from OHWM X__ wetland extends > 200 m from Protection OHWM

Water Quality __ rapid flow through site __ moderate flow through site X__ slow flow through site Improvement __ <50% veg cover __ 50-80 % cover X__ >80% veg cover __ holds <25% overland runoff __ holds 25-50 % overland runoff __ holds > 50 % overland runoff __ soil is coarse gravel, sand, or sandy __ soil is organic mineral mix X__ soil is heavy organic muck and peat Loam

N/A = Not Applicable N/I = No information available FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____5______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Natural __ size <5 acres __ size 5-10 acres X__ size > 10 acres Biological Support __ low veg structure __ 2 level veg X__ high veg structure __ seasonal surface water __ permanent surface water __ open water pools through summer __ one habitat type __ two habitat types X__ > 3 habitat types PAB POW PEM PSS PFO EST __ PAB POW PEM PSS PFO EST _X_ PAB POW PEM PSS PFO EST __ low plant diversity (< 6 species) __ moderate plant diversity __ high plant diversity __ (7-15 species) __ (>15 species) __ > 50% invasive species __ 10 to 50% invasive species _X_ <10% invasive species __ low primary productivity __ moderate primary productivity __ high primary productivity __ low organic accumulation __ moderate organic accumulation X__ high organic accumulation __ low organic export __ low organic export __ high organic export __ few habitat features __ some habitat features _X_ many habitat features __ isolated from upland habitats __ partially connected to upland __ well connected to upland habitats habitats

Overall __ size <5 acres __ size 5-10 acres _X_ size > 10 acres Habitat __ low habitat diversity __ moderate habitat diversity _X_ high habitat diversity __ low sanctuary or refuge __ moderate sanctuary or refuge X__ high sanctuary or refuge Functions

Specific __ low invertebrate habitat __ moderate invertebrate habitat __ high invertebrate habitat Habitat Functions __ low amphibian habitat __ moderate amphibian habitat X__ high amphibian habitat __ low fish habitat __ moderate fish habitat __ high fish habitat __ low mammal habitat __ moderate mammal habitat _X_ high mammal habitat __ low bird habitat __ moderate bird habitat moderate _X_ high bird habitat

Cultural/ __ low educational opportunities __ moderate educational opportunities X__ high educational opportunities Socioeconomic __ low aesthetic value __ moderate aesthetic value _X_ high aesthetic value __ lacks passive and active __ some passive and active __ many passive and active recreational opportunities recreational opportunities recreational opportunities

Notes:

FIELD FORM FOR HYDROLOGY AND SOIL DESCRIPTIONS

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____6______Crew:______Date:_8/31/2006_____

County: Lewis Orthophoto #:______CLASS SUBCLASS

HGM Riverine: Palustrine Flow-through Classification: Depressional: Outflow Slope: Low gradient Alluvial floodplain Flats: OTHER GENERAL HYDROLOGY INFORMATION:

Field Observations: Depth of Surface Water: _0 (in.) Depth to Free Water in Pit:___13__ (in.) Depth to Saturated Soil:____7_____ (in.)

Wetland Hydrology Indicators: ____Inundated __X__Saturated in upper 12 inches __X__Water Marks _X___ Drift Lines ____Sediment Deposits __X__ Drainage Patterns __X__Redoximorhpic Features _X___ Water Stained Leaves _X___ Other (describe)

Evidence of inundation, water level fluctuation, maximum depth, etc. (describe) Soil profile indicates prolonged inundation due to high organic muck content; surface tension cracks on soil.

Inlet: No Yes (Describe) seasonal surface flow occurs during extreme high water level in lake and during winter through spring

Outlet: No Yes (Describe) minor expression of surface drainages that are seasonally inudated

Hydrologic Source/Control (describe): upslope hydrology and precipitation during approx. late Oct – June. Lake level affects hydrology during dry summer months.

SOILS INFORMATION:

Profile Description: Matrix Color Mottle Colors Depth Mottle Horizon (Munsell (Munsell Texture/Concretions/Rhizospheres, etc. (inches) Abundance/Contrast Moist) Moist) 0-8 A 10YR2.1 no Organic muck 8-28 B 10YR6.3 abundant Coarse sandy silt Silt loam

FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:__6______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Flood/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Storm Water __ riverine or lakeshore wetland __ mid-sloped wetland _X_ depressions, headwaters, bogs, flats __ <10% forested cover __ 10 – 30% forested cover X__ > 30% forested cover Control __ unconstrained outlet __ semi-constrained outlet __ culvert/bermed outlet __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage

Base Flow/ __ size <5 acres __ size 5-10 acres X__ size > 10 acres Ground Water __ riverine or lakeshore wetland __ mid-sloped wetland X__ depressions, headwaters, bogs, flats __ located in lower 1/3 of the drainage __ located I middle 1/3 of the drainage __ located in upper 1/3 of the drainage Support __ temporarily flooded or saturated __ seasonally or semi-permanently __ permanently flooded or saturated, or Flooded or saturated intermittently exposed __ no flow-sensitive fish populations __ low flow-sensitive fish populations on-site or downstream on-site or downstream

Erosion/ __ spare grass/herbs or no veg along __ sparse wood or veg along OHWM __ dense wood or veg along OHWM Shoreline OHWM __ wetland extends < 30 m from OHWM __ wetland extends 30-60 m from OHWM X__ wetland extends > 200 m from Protection OHWM

Water Quality __ rapid flow through site __ moderate flow through site X__ slow flow through site Improvement __ <50% veg cover __ 50-80 % cover X__ >80% veg cover __ holds <25% overland runoff __ holds 25-50 % overland runoff __ holds > 50 % overland runoff __ soil is coarse gravel, sand, or sandy __ soil is organic mineral mix X__ soil is heavy organic muck and peat Loam

N/A = Not Applicable N/I = No information available FIELD FORM FOR FUNCTION AND VALUE DESCRIPTIONS Per Semi-quantified Assessment Method (CSS 2000)

DRAWDOWN STUDY EFFECT ON WETLANDS PACKWOOD HYDROELECTRIC PROJECT

Polygon#:______Plot #s:____6______Crew:______Date:______

County: Lewis Orthophoto #:______

Criteria Function Group1 Group 2 Group 3 Natural __ size <5 acres __ size 5-10 acres X__ size > 10 acres Biological Support __ low veg structure __ 2 level veg X__ high veg structure __ seasonal surface water __ permanent surface water __ open water pools through summer __ one habitat type __ two habitat types X__ > 3 habitat types PAB POW PEM PSS PFO EST __ PAB POW PEM PSS PFO EST _X_ PAB POW PEM PSS PFO EST __ low plant diversity (< 6 species) __ moderate plant diversity __ high plant diversity __ (7-15 species) __ (>15 species) __ > 50% invasive species __ 10 to 50% invasive species _X_ <10% invasive species __ low primary productivity __ moderate primary productivity __ high primary productivity __ low organic accumulation __ moderate organic accumulation X__ high organic accumulation __ low organic export __ low organic export __ high organic export __ few habitat features __ some habitat features _X_ many habitat features __ isolated from upland habitats __ partially connected to upland __ well connected to upland habitats habitats

Overall __ size <5 acres __ size 5-10 acres _X_ size > 10 acres Habitat __ low habitat diversity __ moderate habitat diversity _X_ high habitat diversity __ low sanctuary or refuge __ moderate sanctuary or refuge X__ high sanctuary or refuge Functions

Specific __ low invertebrate habitat __ moderate invertebrate habitat __ high invertebrate habitat Habitat Functions __ low amphibian habitat __ moderate amphibian habitat X__ high amphibian habitat __ low fish habitat __ moderate fish habitat __ high fish habitat __ low mammal habitat __ moderate mammal habitat _X_ high mammal habitat __ low bird habitat __ moderate bird habitat moderate _X_ high bird habitat

Cultural/ __ low educational opportunities __ moderate educational opportunities X__ high educational opportunities Socioeconomic __ low aesthetic value __ moderate aesthetic value _X_ high aesthetic value __ lacks passive and active __ some passive and active __ many passive and active recreational opportunities recreational opportunities recreational opportunities

Notes: