U.S. Environmental Protection Agency Region IX FINAL Upper Main Eel River and Tributaries (including Tomki Creek, Outlet Creek and Lake Pillsbury) Total Maximum Daily Loads for Temperature and Sediment Approved by date Original signed December 29, 2004 Alexis Strauss Director, Water Division Note: For further information please contact Palma Risler at 415/972-3451 and
[email protected] or Dan Pingaro at 415/977-4275 and
[email protected] Table of Contents CHAPTER 1: INTRODUCTION 1.1. Overview - 1 1.2. Watershed Characteristics - 2 1.3. Endangered Species Act Consultation - 4 1.4. Organization - 4 CHAPTER 2: PROBLEM STATEMENT 2.1. Fish Population Problems - 5 2.2. Temperature Problems - 7 2.3. Sediment Problems - 14 2.4. Water Quality Standards - 17 CHAPTER 3: TEMPERATURE TMDL 3.1. Interpreting the Existing Water Quality Standards for Temperature - 18 3.2. Temperature Modeling - 20 3.2.1 Temperature and Solar Radiation Modeling - 21 3.2.2 Selection of Scenario Corresponding to Water Quality Standards - 24 3.3.1 Loading Capacity and TMDL – Solar Radiation for all stream reaches - 26 3.3.2 Shade Allocations - 26 3.3.3 Margin of Safety - 27 3.3.4 Seasonal Variation and Critical Conditions - 27 3.4 Instream Heat TMDL – Van Arsdale to Outlet Creek - 28 3.4.1 Selection of Scenario Corresponding to Water Quality Standards - 34 3.4.2 Water Quality Indicators – Van Arsdale to Outlet Creek - 34 3.4.3 Instream Heat Loading Capacity and TMDL - Van Arsdale to Outlet Creek- 34 3.4.4 Instream Heat Allocations – Van Arsdale to Outlet Creek - 35 3.4.5 Margin of Safety - 35 3.4.6 Seasonal Variation and Critical Conditions - 35 CHAPTER 4: SEDIMENT TMDL 4.1.