BUTTE CREEK WATERSHED PROJECT EXISTING CONDITIONS REPORT Prepared For: Butte Creek Watershed Conservancy Prepared By: Butte Creek Watershed Project California State University, Chico August 1998 TABLE OF CONTENTS ACKNOWLEDGEMENTS....................................................................................................................................... i INTRODUCTION.................................................................................................................................................. 1 Executive Summary ............................................................................................................................................... 1 General Stakeholder & Watershed Advisory Committee Process............................................................................. 2 Existing Conditions Report..................................................................................................................................... 2 Geographic Information System (GIS).................................................................................................................... 3 Education Program................................................................................................................................................. 4 Watershed Management Strategy............................................................................................................................ 5 PHYSICAL CONDITIONS OF THE WATERSHED ............................................................................................. 6 1. Location and Overview of the Area.................................................................................................................... 6 Butte Meadows ............................................................................................................................................. 6 Butte Creek Canyon ...................................................................................................................................... 7 Valley Section............................................................................................................................................... 7 Butte Basin ................................................................................................................................................... 7 2. Geology, Basin Morphology, and Hydrologic System ........................................................................................ 9 Introduction .................................................................................................................................................. 9 Butte Meadows ............................................................................................................................................. 9 Upper Butte Creek Canyon.......................................................................................................................... 10 Middle Butte Creek Canyon ........................................................................................................................ 11 Lower Butte Creek Canyon ......................................................................................................................... 12 Valley Section and Butte Basin ................................................................................................................... 13 Stream Flows .............................................................................................................................................. 20 Data Gaps ................................................................................................................................................... 23 3. Fluvial Geomorphology................................................................................................................................... 25 Introduction ................................................................................................................................................ 25 Flow Regime............................................................................................................................................... 25 Channel Morphology................................................................................................................................... 26 Channel Stability......................................................................................................................................... 27 Erosion and Sedimentation.......................................................................................................................... 28 Problem Areas ............................................................................................................................................ 28 4. Water Supply and Service Areas of Water Suppliers ........................................................................................ 29 Historical Background................................................................................................................................. 29 Water Suppliers .......................................................................................................................................... 29 Groundwater............................................................................................................................................... 35 5. Water Quality.................................................................................................................................................. 39 Introduction ................................................................................................................................................ 39 Water Quality Goals.................................................................................................................................... 39 Sources of Water Quality Monitoring Information ....................................................................................... 39 Water Quality Monitoring ........................................................................................................................... 39 Analysis of Historic Monitoring and Water Quality Data ............................................................................. 41 Current Sampling Methods.......................................................................................................................... 43 Monitored Water Quality Parameters........................................................................................................... 43 Ground Water Quality Concerns.................................................................................................................. 51 Data Gaps ................................................................................................................................................... 53 Future Monitoring of Water Quality Parameters .......................................................................................... 57 6. Ecology........................................................................................................................................................... 57 Plant Communities and Distributions.................................................................................................................... 57 Valley Communities.................................................................................................................................... 57 Foothill and Montane Communities............................................................................................................. 60 Sensitive Botanical Resources ..................................................................................................................... 63 Management Concerns................................................................................................................................ 65 Wildlife In The Butte Creek Watershed ................................................................................................................ 68 Wildlife Values of Past Riparian and Fresh-Water Marsh Habitats............................................................... 68 Current Status of Special Status Wildlife Populations .................................................................................. 69 Threats by Exotic Species............................................................................................................................ 74 Management Concerns................................................................................................................................ 79 Fisheries And Aquatic Resources.......................................................................................................................... 80 A Brief Historic Perspective........................................................................................................................ 80 Hydraulic Mining Impacts........................................................................................................................... 81 Historic Wetlands ....................................................................................................................................... 81 Stream Habitat Conditions........................................................................................................................... 82 Fishes of Butte Creek .................................................................................................................................