Trask River Watershed Analysis TRASK RIVER WATERSHED ANALYSIS FINAL REPORT AUGUST 2003 A Report by E&S Environmental Chemistry, Inc. P.O. Box 609 Corvallis, OR 97339 Kai U. Snyder Timothy J. Sullivan Deian L. Moore Richard B. Raymond Erin H. Gilbert Submitted to Oregon Department of Forestry and U.S. Department of Interior, Bureau of Land Management John Hawksworth, Project Manager Trask River Watershed Analysis ii Table of Contents LIST OF FIGURES ...................................................................................................................... x LIST OF TABLES......................................................................................................................xii ACKNOWLEDGMENTS .........................................................................................................xiv CHAPTER 1. CHARACTERIZATION...................................................................................1-1 1.1 Physical ........................................................................................................1-1 1.1.1 Size and Setting ..........................................................................................1-1 1.1.2 Topography.................................................................................................1-1 1.1.3 Ecoregions..................................................................................................1-3 1.1.4 Geology and Geomorphology.....................................................................1-3 1.1.5 Soils ........................................................................................................1-5 1.1.6 Erosion and Sediment.................................................................................1-5 1.1.7 Climate and Precipitation ...........................................................................1-6 1.1.8 Hydrology...................................................................................................1-6 1.1.9 Water Quality..............................................................................................1-7 1.1.10 Stream Channel...........................................................................................1-8 1.2 Biological ........................................................................................................1-8 1.2.1 Vegetation Characteristics..........................................................................1-8 1.2.2 Fish and Wildlife Habitat..........................................................................1-10 1.2.2.1 Aquatic.......................................................................................1-10 1.2.2.2 Terrestrial...................................................................................1-11 1.3 Social ....................................................................................................1-13 1.3.1 Population.................................................................................................1-13 1.3.2 Ownership.................................................................................................1-14 1.3.3 Land Use...................................................................................................1-14 1.3.4 Human Uses..............................................................................................1-15 1.3.4.1 Forestry.......................................................................................1-15 1.3.4.2 Agriculture.................................................................................1-16 1.3.4.3 Urban and Rural Residential ......................................................1-16 1.3.4.4 Recreation...................................................................................1-16 CHAPTER 2. REFERENCE CONDITIONS...........................................................................2-1 2.1 Introduction ......................................................................................................2-1 2.2 Aquatic ......................................................................................................2-1 2.2.1 Hydrology and Water Quantity ..................................................................2-1 2.2.2 Erosion ......................................................................................................2-3 2.2.3 Water Quality..............................................................................................2-4 2.2.4 Stream Channel...........................................................................................2-4 2.2.5 Aquatic Species and Habitat.......................................................................2-5 2.3 Terrestrial ......................................................................................................2-7 2.3.1 Landscape Vegetation Pattern ....................................................................2-7 2.3.1.1 North Coast Region......................................................................2-7 2.3.1.2 Trask Watershed...........................................................................2-7 2.3.1.3 Sensitive Plant Species.................................................................2-8 Trask River Watershed Analysis iii 2.3.2 Wildlife Species and Habitat ......................................................................2-8 2.3.2.1 Terrestrial Habitat........................................................................2-8 2.3.2.2 Riparian, Wetland, and Estuarine Habitats..................................2-9 2.4 Social ....................................................................................................2-10 2.4.1 Historical Changes in Landscape Pattern .................................................2-10 2.4.2 Human Uses Prior to European Settlement ..............................................2-12 2.4.3 European Settlement.................................................................................2-13 2.4.3.1 Agricultural Operations..............................................................2-14 2.4.3.2 Timber Operations......................................................................2-15 2.4.3.3 Road Building............................................................................2-18 2.4.3.4 Wetland Conversion...................................................................2-18 2.4.3.5 Channel Modification.................................................................2-20 2.4.3.6 Expansion of Urban and Rural Residential Land Uses ..............2-21 2.4.4 Effects of Native Americans and European Settlers Upon Fire Regimes ....................................................................................................2-22 CHAPTER 3. CURRENT CONDITIONS ...............................................................................3-1 3.1 Aquatic Ecosystems................................................................................................3-1 3.1.1 Hydrologic Characterization.......................................................................3-1 3.1.1.1 Flooding.......................................................................................3-3 3.1.1.2 Groundwater.................................................................................3-4 3.1.1.3 Human Impacts on Hydrology .....................................................3-4 3.1.2 Water Quantity............................................................................................3-6 3.1.3 Stream Channel...........................................................................................3-9 3.1.3.1 Stream Morphology and Sediment Transport Processes..............3-9 3.1.3.2 Effects of Human Influences Upon Stream Morphology...........3-13 3.1.3.3 Stream Enhancement Projects....................................................3-14 3.1.4 Erosion and Sediment...............................................................................3-15 3.1.4.1 Overview of Erosion and Sediment Processes...........................3-15 3.1.4.2 Mass-Wasting and Slope Stability in The Trask River Watershed...................................................................................3-16 3.1.4.3 Human Impacts on Erosional Processes and Sediment Production ..................................................................................3-17 3.1.4.4 Effects of Sedimentation on Barney Reservoir..........................3-17 3.1.5 Water Quality............................................................................................3-18 3.1.5.1 Streams on The 1998 ODEQ 303(D) List..................................3-18 3.1.5.2 Water Quality Data and Evaluation Criteria ..............................3-19 3.1.5.3 Water Quality Parameters ..........................................................3-25 3.1.5.4 Summary of Water Quality Concerns ........................................3-33 3.1.5.5 Water Quality Trends.................................................................3-34 3.1.6 Aquatic Species and Habitat.....................................................................3-36 3.1.6.1 Fish and Fish Habitat..................................................................3-36 3.1.6.2 Amphibians ................................................................................3-47 3.1.6.3 Reptiles.......................................................................................3-48 3.1.6.4 Wetland Species and Habitat......................................................3-48 3.2 Terrestrial Ecosystems..........................................................................................3-50