Luckiamute/Ash Creek Study Draft – do not cite or distribute Read Me This report represents the final draft of the Luckiamute / Ash Creek Watershed Assessment. We are looking for your input. Before you begin, please review the purpose and scope of this assessment. This report will be reformatted following this review. This report has undergone a major reorganization since the last draft. Therefore, some of the maps may appear out of sequence AND some of the tables may not be appropriately referenced. The Table of Contents will not be correct until the final formatting is complete. The Executive Summary will follow the organization of the report and will be completed in the final report. Not all the references appear in the Literature Cited section. We are asking reviewers to focus on the content of the report rather than the formatting. Please answer these three questions in your review: 1. Is the information presented accurate? Do you know of important information that is not included? 2. Are there errors in the interpretation of the information? 3. Are the methods used appropriate? Thank you for your time. This will be a better assessment because of your input. --- Ralph Garono, April 14 2004 Earth Design Consultants, Inc. 4/14/2004 Page - 1 - of 278 Luckiamute/Ash Creek Study Draft – do not cite or distribute Table of Contents 1 Introduction................................................................................- 6 - 1.1 List of Acronyms and Abbreviations................................................... - 6 - 1.2 List of Maps ........................................................................................... - 7 - 1.3 Executive Summary.............................................................................. - 7 - 1.4 Purpose and Goals ............................................................................... - 7 - Purpose...................................................................................................................... - 7 - Project Goals.............................................................................................................. - 7 - 1.5 Definitions & Strategy......................................................................... - 11 - Strategy.................................................................................................................... - 14 - 2 How to Use This Report..........................................................- 16 - 3 Data...........................................................................................- 17 - 3.1 Use Restrictions.................................................................................. - 17 - 3.2 Use of Existing Data ........................................................................... - 17 - 3.3 Scale of Data and Units of Comparison ............................................ - 17 - 3.4 Accuracy & Uncertainty...................................................................... - 18 - 4 Watershed Characteristics .....................................................- 19 - Location..................................................................................................... - 19 - Climate....................................................................................................... - 19 - Temperature............................................................................................................. - 19 - Precipitation..............................................................................................................- 20 - Elevation.................................................................................................... - 24 - Lithology.................................................................................................... - 27 - Soils ........................................................................................................... - 34 - Hydric Soils .............................................................................................................. - 34 - Erodible Soils ........................................................................................................... - 42 - Ecoregions and Physiographic Provinces................................................................ - 42 - 5 Human Habitation....................................................................- 47 - Settlement.................................................................................................. - 47 - Historic Settlement ...................................................................................................- 47 - Historic Sites ............................................................................................................ - 48 - Cities ........................................................................................................................ - 48 - Human Population .................................................................................... - 50 - Transportation........................................................................................... - 53 - Roads ....................................................................................................................... - 53 - Railroads .................................................................................................................. - 54 - Airports ..................................................................................................................... - 54 - Ports ......................................................................................................................... - 55 - Land Use.................................................................................................... - 55 - Mills ..........................................................................................................................- 55 - Earth Design Consultants, Inc. 4/14/2004 Page - 2 - of 278 Luckiamute/Ash Creek Study Draft – do not cite or distribute Mining....................................................................................................................... - 58 - Landfills .................................................................................................................... - 60 - Military Facilities....................................................................................................... - 60 - Wildlife Preserves .................................................................................................... - 61 - Land Ownership........................................................................................ - 61 - Zoning and Regulations ........................................................................... - 64 - Recommendations.................................................................................... - 65 - 6 Physical Processes.................................................................- 66 - 6.1 Hydrology, Water Use and Water Quality ......................................... - 66 - 6.1.1 Hydrology ........................................................................................................- 66 - Streams ............................................................................................................. - 66 - Springs .............................................................................................................. - 77 - 6.1.2 Water Use ....................................................................................................... - 78 - Surface Water Use ............................................................................................ - 79 - Ground Water.................................................................................................... - 87 - 6.1.3 Water Quality ..................................................................................................- 92 - Non-Point Source Pollution ............................................................................... - 95 - Water Temperature ........................................................................................... - 95 - Water Quality Evaluation................................................................................... - 98 - High Quality Waters ........................................................................................- 103 - Water Quality Monitoring Data ........................................................................ - 103 - 6.1.4 Stream Flow and Flooding ............................................................................ - 105 - Peak Flows ...................................................................................................... - 105 - Impact of Roads .............................................................................................. - 106 - Rain-on-Snow...................................................................................................... 109 6.1.5 Flooding ............................................................................................................ 109 6.2 Erosional Processes............................................................................. 110 6.2.1 Surface erosion ................................................................................................. 110 Soils..................................................................................................................... 110 Roads .................................................................................................................. 110 Streambank Erosion...........................................................................................