MIAMI RIVER WATERSHED ASSESSMENT Final Report December, 2001 A Report by: E&S Environmental Chemistry, Inc. P.O. Box 609 Corvallis, OR 97339 Kai U. Snyder Timothy J. Sullivan Richard B. Raymond Joseph M. Bischoff Shawn White Susan K. Binder Submitted to: Tillamook County Performance Partnership P.O. Box 493 Garibaldi, OR 97118 Miami River Watershed Assessment December, 2001 Page ii TABLE OF CONTENTS LIST OF FIGURES........................................................... vi LIST OF TABLES........................................................... vii ACKNOWLEDGMENTS .......................................................x CHAPTER 1. INTRODUCTION ............................................... 1-1 1.1 Purpose and Scope................................................... 1-1 1.1.1 The Decision Making Framework ................................. 1-1 1.1.2 Geographic Information Systems (GIS) Data Used in this Assessment .... 1-2 1.1.3 Data Confidence .............................................. 1-6 1.2 Setting ............................................................ 1-8 1.3 Ecoregions........................................................ 1-11 1.4 Population ........................................................ 1-11 1.5 Climate and Topography ............................................. 1-12 1.6 Geology.......................................................... 1-13 1.7 Vegetation........................................................ 1-14 1.7.1 Potential Natural Vegetation ............................... 1-14 1.7.2 Historic Floodplain Vegetation .................................. 1-16 1.7.3 Current Vegetation ........................................... 1-16 1.7.4 Large Conifers .............................................. 1-19 1.7.5 Open Areas ................................................. 1-21 1.8 Land Use......................................................... 1-21 1.9 Channel Habitat Types .............................................. 1-23 1.10 History ........................................................... 1-28 1.11 Fire History ....................................................... 1-28 CHAPTER 2. FISHERIES ........ 2-1 2.1 Introduction ........................................................ 2-1 2.2 Fish Presence....................................................... 2-1 2.3 Species of Concern .................................................. 2-2 2.4 Coho ............................................................. 2-3 2.4.1 Life History ................................................. 2-3 2.4.2 Listing Status ................................................. 2-4 2.4.3 Population Status .............................................. 2-5 2.4.4 Factors Responsible for Decline .................................. 2-6 2.4.5 Species Distribution ........................................... 2-7 2.4.6 Hatcheries ................................................... 2-9 2.5 Chinook .......................................................... 2-10 2.5.1 Life History ................................................. 2-10 2.5.2 Listing Status ................................................ 2-10 2.5.3 Population Status ............................................. 2-10 2.5.4 Factors Responsible for Decline ................................. 2-12 2.5.5 Species Distribution .......................................... 2-14 2.6 Coastal Cutthroat................................................... 2-16 Miami River Watershed Assessment December, 2001 Page iii 2.6.1 Life History ................................................. 2-16 2.6.2 Listing Status ................................................ 2-16 2.6.3 Population Status ............................................. 2-16 2.6.4 Factors for Decline ........................................... 2-18 2.6.5 Species Distribution .......................................... 2-18 2.6.6 Species Interactions ........................................... 2-18 2.7 Chum............................................................ 2-19 2.7.1 Life History ................................................. 2-19 2.7.2 Listing Status ................................................ 2-19 2.7.3 Population Status ............................................. 2-20 2.7.4 Factors Responsible for Decline ................................. 2-20 2.7.5 Species Distribution .......................................... 2-21 2.7.6 Hatcheries .................................................. 2-23 2.8 Steelhead......................................................... 2-23 2.8.1 Life History ................................................. 2-23 2.8.2 Listing Status ................................................ 2-24 2.8.3 Population Status ............................................. 2-24 2.8.4 Factors Responsible for Decline ................................. 2-25 2.8.5 Species Distribution .......................................... 2-26 2.8.6 Hatcheries .................................................. 2-26 CHAPTER 3. AQUATIC AND RIPARIAN HABITATS ............................ 3-1 3.1 Introduction ........................................................ 3-1 3.2 Aquatic Habitat Data................................................. 3-2 3.2.1 Stream Morphology and Substrates ............................... 3-5 3.2.2 Large Woody Debris ........................................... 3-6 3.2.3 Large Woody Debris Recruitment Potential ......................... 3-9 3.3 Riparian Conditions ................................................ 3-11 3.4 Fish Passage Barriers................................................3-14 3.4.1 Culverts .................................................... 3-14 3.4.2 Natural Barriers .............................................. 3-15 3.5 Channel Modifications .............................................. 3-15 3.5.1 Channelization, Diking, and Dredging ............................ 3-17 3.5.2 Floodplain Development ....................................... 3-18 3.5.3 Gravel Removal .............................................. 3-19 3.6 Wetlands ......................................................... 3-20 3.6.1 National Wetlands Inventory .................................... 3-20 3.6.2 Wetland Extent and Types ..................................... 3-21 3.6.3 Wetlands and Salmonids ....................................... 3-21 3.6.4 Filling and Diking of Wetlands .................................. 3-24 CHAPTER 4. HYDROLOGY ................................................. 4-1 4.1 Introduction ............................ 4-1 4.2 Hydrologic Characterization........................................... 4-1 4.2.1 Watershed and Peak Flow Characterization .......................... 4-1 4.2.2 Stream Flow .................................................. 4-3 4.3 Potential Land Use Impacts on Peak Flows ............................... 4-4 Miami River Watershed Assessment December, 2001 Page iv 4.3.1 Forestry ..................................................... 4-5 4.3.2 Agriculture and Rangeland ...................................... 4-5 4.3.3 Forest and Rural Roads ......................................... 4-6 4.3.4 Urban and Rural Residential Areas ................................ 4-7 4.3.5 Other Potential Hydrologic Impacts ............................... 4-7 4.4 Conclusions........................................................ 4-8 CHAPTER 5. WATER USE .................................................. 5-1 5.1 In-stream Water Rights............................................... 5-2 5.2 Consumptive Water Use.............................................. 5-2 5.2.1 Irrigation .................................................... 5-2 5.3 Water Availability ................................................... 5-4 5.3.1 Water Availability Models ...................................... 5-4 5.3.2. Low Flow History of the Miami River .............................. 5-5 5.3.3 Flow Restoration Priorities under the Oregon Plan for Salmon .......... 5-7 5.4 Conclusions........................................................ 5-7 CHAPTER 6. SEDIMENT SOURCES .......................................... 6-1 6.1 Introduction ........................................................ 6-1 6.2 Screening for Potential Sediment Sources ................................ 6-2 6.3 Slope Instability ..................................................... 6-2 6.4 Road Instability ..................................................... 6-6 6.5 Road Runoff ....................................................... 6-7 6.6 Streambank Erosion ................................................. 6-8 6.7 The Tillamook Burn ................................................. 6-9 6.8 Conclusions....................................................... 6-10 CHAPTER 7. WATER QUALITY ............................................. 7-1 7.1 Introduction ........................................................ 7-1 7.1.1 Assessment Overview .......................................... 7-1 7.1.2 Components of Water Quality .................................... 7-1 7.2 Beneficial Uses ..................................................... 7-3 7.2.1 Water Uses Sensitive to Water Quality ............................. 7-4 7.3 Pollutant Sources.................................................... 7-4 7.3.1 Point Sources ................................................. 7-4 7.3.2 Non-point Sources ............................................. 7-4 7.3.3 Water Quality Limited Water Bodies .............................. 7-6 7.3.4 Oregon Water Quality Index ....................................