Volume II, Chapter 16 Wind River Subbasin
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Volume II, Chapter 16 Wind River Subbasin TABLE OF CONTENTS 16.0 WIND RIVER SUBBASIN ...................................................................................... 16-1 16.1 Subbasin Description............................................................................................. 16-1 16.1.1 Topography & Geology................................................................................. 16-1 16.1.2 Climate .......................................................................................................... 16-1 16.1.3 Land Use/Land Cover.................................................................................... 16-1 16.2 Focal Fish Species ................................................................................................. 16-5 16.2.1 Spring Chinook—Wind Subbasin .................................................................. 16-5 16.2.2 Fall Chinook—Wind Subbasin ...................................................................... 16-8 16.2.3 Mid-Columbia Bright Late Fall Chinook—Wind Subbasin ........................ 16-11 16.2.4 Chum—Wind Subbasin................................................................................ 16-14 16.2.5 Summer Steelhead—Wind Subbasin............................................................ 16-16 16.2.6 Winter Steelhead—Wind Subbasin.............................................................. 16-19 16.3 Potentially Manageable Impacts.......................................................................... 16-21 16.4 Hatchery Programs .............................................................................................. 16-22 16.5 Fish Habitat Conditions....................................................................................... 16-26 16.5.1 Passage Obstructions .................................................................................. 16-26 16.5.2 Stream Flow................................................................................................. 16-26 16.5.3 Water Quality .............................................................................................. 16-28 16.5.4 Key Habitat.................................................................................................. 16-29 16.5.5 Substrate & Sediment .................................................................................. 16-29 16.5.6 Woody Debris .............................................................................................. 16-30 16.5.7 Channel Stability ......................................................................................... 16-31 16.5.8 Riparian Function ....................................................................................... 16-31 16.5.9 Floodplain Function.................................................................................... 16-31 16.6 Fish/Habitat Assessments.................................................................................... 16-32 16.6.1 Population Analysis..................................................................................... 16-32 16.6.2 Restoration and Preservation Analysis ....................................................... 16-35 16.6.3 Habitat Factor Analysis .............................................................................. 16-39 16.7 Integrated Watershed Assessment (IWA) ........................................................... 16-43 16.7.1 Results and Discussion................................................................................ 16-43 16.7.2 Predicted Future Trends.............................................................................. 16-50 16.8 References ........................................................................................................... 16-52 16.0 Wind River Subbasin 16.1 Subbasin Description 16.1.1 Topography & Geology The Wind River subbasin covers about 143,504 acres (224 mi2) in central Skamania County. The headwaters of the mainstem arise in the McClellan Meadows area in the southern Gifford Pinchot National Forest (GPNF). The major tributaries in the basin include the Little Wind River, Bear Creek, Panther Creek, Trout Creek, Trapper Creek, Dry Creek, Falls Creek, and Paradise Creek. Elevation in the basin ranges from 80 to 3,900 feet. The northwest portion of the basin is steep and the northeast portion is relatively flat and consists of high elevation meadows. Trout Creek, a major tributary to the west, has a broad alluvial bench (Trout Creek Flats) in the upper central portion of the basin. A broad alluvial valley extends along several miles of the middle mainstem before entering into a steep V-shaped canyon in the lower 20 miles of stream. The lower southeast portion of the basin, including the Panther Creek and Little Wind River basins, is quite steep. Shipherd Falls, actually a set of four 10-15 foot falls, is located at approximately RM 2 and historically blocked all anadromous fish except for steelhead, until it was laddered in the 1950s. Basin geologic history consists of old and new volcanic activity combined with more recent glacial and alluvial processes. The older basalt flows date back 12 to 25 million years, while the newer ones emanating from Trout Creek Hill are as recent as 300,000 years ago. The older material, which makes up most of the basin, is the most susceptible to erosion due to weathering into finer material. Relatively recent glacial activity contributed glacial sediments and has shaped river valleys. Alluvial deposits from the massive Bretz Floods, which originated from eastern Washington during the late Pleistocene, have resulted in highly erodable soils in portions of the lower basin. 16.1.2 Climate The climate is marine-influenced, consisting of cool, wet winters and warm, dry summers. Mean annual precipitation is 109 inches at Stabler. Most of the precipitation falls from November through April (WRCC 2003). 70% of the basin is in the rain-on-snow zone, with low elevation areas in the rain-dominated zone and the highest elevation areas in the snow-dominated zone. 16.1.3 Land Use/Land Cover The subbasin is 93% forested. Non-forested lands include alpine meadows in the upper northeast basin and areas of development in lower elevation, privately-owned areas. Forest stands above 3,500 feet are generally in the Pacific silver fir plant association, while lower elevation areas tend to be in the Hemlock zone. Approximately 9.6% of the land is private, while almost all of the remainder lies within the GPNF. Forestry land uses dominate the subbasin. The percentage of the forest in late-successional forest stages has decreased from 83,500 acres to 31,800 acres since pre-settlement times. This change is attributed to timber harvest and forest fires (USFS 1996). The largest population centers are the towns of Carson and Stabler. Carson draws its water supply from Bear Creek, a Wind River tributary. The year 2000 population of the subbasin was estimated at 2,096 persons and is expected to increase to 3,077 by 2020 (Greenberg and Callahan 2002). Land ownership and land cover are illustrated in Figure 16-1 WIND II, 16-1 May 2004 and Figure 16-2. Figure 16-3 displays the pattern of landownership for the basin. Figure 16-4 displays the pattern of land cover / land-use. Non- Private forest 11% 8% Late Seral Early 25% Seral 26% Federal Mid Seral 89% 41% Figure 16-1. Wind River subbasin land Figure 16-2. Wind River subbasin land cover ownership WIND II, 16-2 May 2004 Figure 16-3. Landownership within the Wind basin. Data is WDNR data that was obtained from the Interior Columbia Basin Ecosystem Management Project (ICBEMP). WIND II, 16-3 May 2004 Figure 16-4. Land cover within the Wind basin. Data was obtained from the USGS National Land Cover Dataset (NLCD). WIND II, 16-4 May 2004 16.2 Focal Fish Species 16.2.1 Spring Chinook—Wind Subbasin ESA: Not listed (non-native species) SASSI: Healthy 2002 Distribution • Historically, spring chinook were not found in the Wind River basin • A ladder was constructed at Shipherd Falls (RM 2) in the 1956 as part of a spring chinook introduction program, providing fish access to the upper watershed • Currently, natural spawning occurs in limited numbers from the mouth of Paradise Creek (RM 25) downstream approximately 10 miles Life History • Spring chinook return to the Wind River from March through June; spring chinook counts peak at Bonneville Dam in late April • Spawning in the Wind River occurs between early August and mid-September, with peak activity in late August • Age ranges from 3-year old jacks to 6-year old adults, with 4- and 5-year olds usually the dominant age class (averages are 58.5% and 38.0%, respectively) • Fry emerge between November and March, depending on time of egg deposition and water temperature; spring chinook fry spend one full year in fresh water, and emigrate in their second spring as age-2 smolts WIND II, 16-5 May 2004 Spring Chinook Hatchery Run Size, Spawner escapement surveys for Sport Harvest and Tribal Harvest & Spring chinook hatchery releases in Subsistence, 1993-2002 2.5 the Wind River , 1970-2001 30 4 the Wind River, 1975-2000 Run Size Sport Harvest 25 2.0 Tribal Harvest & Subsistence 3 20 1.5 15 2 1.0 10 1 0.5 Escapement (thousands) 5 Number of (thousands)Fish Hatchery Releases (millions) Hatchery Releases 0.0 0 0 1965 1975 1985 1995 2005 1990 1995 2000 2005 1965 1975 1985 1995 2005 Diversity • Spring chinook did not historically return to the Wind River • Spring chinook were introduced to the Wind River basin; brood stock is mixed upriver spring chinook