Alvord Lake Subbasin Total Maximum Daily Load (TMDL) & Water Quality Management Plan (WQMP) Prepared by: December 2003 ALVORD LAKE SUBBASIN TMDL DECEMBER 2003 . Primary authors are: Bruce Hammon, Bonnie Lamb, Dick Nichols, Brian Kasper, Matt Boyd December 2003 For more information contact: Greg Aldrich, Manager of Watershed Management Section Department of Environmental Quality 811 Southwest 6th Avenue Portland, Oregon 97204 [email protected] Dick Nichols, Manager of Eastern Region Department of Environmental Quality 2146 Northeast 4th Street Bend, Oregon 97701 [email protected] OREGON DEPARTMENT OF ENVIRONMENTAL QUALITY ALVORD LAKE SUBBASIN TMDL DECEMBER 2003 ALVORD LAKE SUBBASIN TOTAL MAXIMUM DAILY LOAD (TMDL) TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................... I WATER QUALITY SUMMARY................................................................................................................... I TMDL SUMMARIES ................................................................................................................................... I Alvord Lake Subbasin Stream Temperature TMDL (Chapter II) ............................................................ i Willow Creek (Trout Creek Mountains) Temperature TMDL (Chapter III)............................................. ii Willow Creek (Trout Creek Mountains) Dissolved Oxygen TMDL (Chapter IV).................................... ii WATER QUALITY MANAGEMENT PLAN SUMMARY ............................................................................ II CHAPTER I: OVERVIEW AND BACKGROUND.........................................................................................1 1.1 INTRODUCTION.................................................................................................................................2 1.2 OVERVIEW OF TOTAL MAXIMUM DAILY LOADS ...........................................................................3 1.2.1 Elements of a TMDL .....................................................................................................................3 1.2.3 TMDL Implementation via the Water Quality Management Plan .................................................3 1.2.4 Implementation and Adaptive Management Issues......................................................................5 1.4 ALVORD LAKE SUBBASIN OVERVIEW............................................................................................7 1.4.1 Geology.........................................................................................................................................7 1.4.2 Climate..........................................................................................................................................7 1.4.3 Stream Flow................................................................................................................................10 1.4.4 Land Use and Ownership ...........................................................................................................10 1.4.5 Fisheries .....................................................................................................................................13 CHAPTER II: STREAM TEMPERATURE TMDL.......................................................................................19 2.1 OVERVIEW .......................................................................................................................................20 2.1.1 Summary of Temperature TMDL Development and Approach ..................................................20 2.1.2 Salmonid Thermal Requirements ...............................................................................................28 2.2 TARGET IDENTIFICATION – CWA §303(D)(1) ...............................................................................29 2.2.1 Sensitive Beneficial Use Identification........................................................................................29 2.2.2 Water Quality Standard Identification .........................................................................................30 2.2.3 Pollutant Identification.................................................................................................................31 2.3 SEASONAL VARIATION - CWA §303(D)(1) ....................................................................................34 2.4 EXISTING HEAT SOURCES - CWA §303(D)(1) ..............................................................................39 2.4.1 Stream Heating Processes – Background Information...............................................................39 2.4.2 Analytical Methodology...............................................................................................................40 2.4.3 Nonpoint Sources of Heat...........................................................................................................40 2.4.4 Point Sources of Heat.................................................................................................................65 2.5 LOADING CAPACITY – 40 CFR 130.2(F) ........................................................................................65 2.5.1 Nonpoint Sources .......................................................................................................................66 2.5.2 Point Sources..............................................................................................................................66 2.6 ALLOCATIONS – 40 CFR 130.2(G) AND (H)...................................................................................70 2.7 SURROGATE MEASURES – 40 CFR 130.2(I) ................................................................................70 2.7.1 Site Specific Effective Shade Surrogate Measures ....................................................................71 OREGON DEPARTMENT OF ENVIRONMENTAL QUALITY ALVORD LAKE SUBBASIN TMDL DECEMBER 2003 2.7.2 Effective Shade Curves for Ecological Provinces.......................................................................72 2.8 MARGINS OF SAFETY – CWA §303(D)(1)......................................................................................79 2.8.1 Implicit Margins of Safety............................................................................................................80 2.9 WATER QUALITY STANDARD ATTAINMENT ANALYSIS – CWA §303(D)(1) ..............................81 CHAPTER III: WILLOW CREEK TEMPERATURE TMDL ........................................................................83 3.1 OVERVIEW .......................................................................................................................................84 3.2 TARGET IDENTIFICATION – CWA §303(D)(1) ...............................................................................86 3.2.1 Sensitive Beneficial Uses ...........................................................................................................86 3.2.2 Water Quality Standard Identification .........................................................................................86 3.2.3 Pollutant Identification.................................................................................................................88 3.3 SEASONAL VARIATION - CWA §303(D)(1) ....................................................................................88 3.4 EXISTING HEAT SOURCES - CWA §303(D)(1) ..............................................................................89 3.4.1 Stream Heating Processes – Background Information...............................................................89 3.4.2 Analytical Methodology...............................................................................................................89 3.4.3 Nonpoint Sources of Heat...........................................................................................................91 3.4.4 Point Sources of Heat.................................................................................................................95 3.4.5 Beaver Dams and Hotsprings.....................................................................................................95 3.5 LOADING CAPACITY - 40 CFR 130.2(F).........................................................................................96 3.5.1 Nonpoint Sources .......................................................................................................................97 3.5.2 Point Sources..............................................................................................................................98 3.6 ALLOCATIONS - 40 CFR 130.2(G) AND (H)....................................................................................98 3.7 SURROGATE MEASURES – 40 CFR 130.2(I) ................................................................................99 3.7.1 Site Specific Effective Shade Surrogate Measures ....................................................................99 3.7.2 Regional Effective Shade Curves.............................................................................................101 3.8 MARGINS OF SAFETY – CWA §303(D)(1)....................................................................................104 3.8.1 Implicit Margins of Safety..........................................................................................................104 3.9 WATER QUALITY STANDARD ATTAINMENT ANALYSIS – CWA §303(D)(1) ............................104 CHAPTER