Illinois EPA Clean Lakes Program Phase 1 Diagnostic/Feasibility Study of Lake Vermilion, Vermilion County, IL (Final Draft Submittal – 2/2/04) (A Division of the Illinois Dept. of Natural Resources) with assistance from: Consumers Illinois Water Company Illinois Environmental Protection Agency Phase I: Diagnostic Study of Lake Vermilion, Vermilion County, Illinois Shun Dar Lin and William Bogner Prepared for The Consumers Illinois Water Company and Illinois Environmental Protection Agency ii CONTENTS Page PART 1: DIAGNOSTIC STUDY OF LAKE VERMILION ................................................... 1 Introduction............................................................................................................................... 1 Lake Identification and Location...................................................................................... 2 Acknowledgments............................................................................................................. 5 Study Area ................................................................................................................................ 7 Lake Vermilion ................................................................................................................ 7 Watershed ......................................................................................................................... 10 Climatologic Conditions of the Study Area...................................................................... 11 Geological and Soil Characteristics of the Drainage Basin.............................................. 13 Drainage Area........................................................................................................... 13 Geology, Soils, and Topography .............................................................................. 13 Geologic Conditions................................................................................................. 14 Hydrogeologic Conditions................................................................................................ 18 Hydrologic Description of Lake Vermilion ..................................................................... 19 Hydrologic System.................................................................................................... 19 Surface Inflow and Outflow Conditions................................................................... 20 Public Access to the Lake Area ........................................................................................ 21 iii Size and Economic Structure of Potential User Population.............................................. 25 Potential User Population......................................................................................... 25 Economic Characteristics.......................................................................................... 26 Historical Lake Uses......................................................................................................... 31 Public Water Supply (Water Treatment Plant) ......................................................... 31 Recreation Uses........................................................................................................ 33 Residential Uses........................................................................................................ 34 Population Segments Adversely Affected by Lake Degradation ..................................... 34 Comparison to Other Lakes in the Region........................................................................ 36 Point Source Discharges ................................................................................................... 37 Land Use and Nonpoint Pollution Loadings..................................................................... 45 Watershed Land Use................................................................................................. 45 Nonpoint Pollution Sources...................................................................................... 48 Watershed Soil Loss.......................................................................................... 48 Nutrient Loadings.............................................................................................. 49 Past and Current Watershed Protection/Restoration Activities......................................... 51 North Fork Drainage Project..................................................................................... 51 The Lake Vermilion Water Quality Coalition .......................................................... 53 North Fork River Habitat Enhancement Project....................................................... 54 Baseline Limnological Data...................................................................................................... 57 Morphometric Data........................................................................................................... 57 Materials and Methods...................................................................................................... 58 iv Page Field Measurements.................................................................................................. 58 Water Chemistry....................................................................................................... 60 Chlorophyll ............................................................................................................... 60 Macrophytes.............................................................................................................. 61 Sediment ........................................................................................................................... 62 Data Analyses................................................................................................................... 62 In-Lake Water Quality ...................................................................................................... 64 Physical Characteristics............................................................................................ 64 Temperature and Dissolved Oxygen................................................................. 64 Turbidity ........................................................................................................... 73 Secchi Disc Transparency................................................................................. 74 Chemical Characteristics.......................................................................................... 76 pH...................................................................................................................... 76 Alkalinity .......................................................................................................... 77 Total Alkalinity......................................................................................... 78 Phenolphthalein Alkalinity........................................................................ 79 Conductivity...................................................................................................... 79 Total Suspended Solids..................................................................................... 81 Volatile Suspended Solids................................................................................ 83 Nitrogen ............................................................................................................ 84 Ammonia-Nitrogen ................................................................................... 86 Total Kjeldahl Nitrogen............................................................................ 87 v Nitrate/Nitrite-Nitrogen............................................................................. 88 Phosphorus........................................................................................................ 88 Total Phosphorus....................................................................................... 90 Dissolved Phosphorus ............................................................................... 91 Limiting Nutrient.............................................................................................. 92 Chlorophyll ....................................................................................................... 93 Metals................................................................................................................102 Organics ............................................................................................................103 Biological Characteristics.........................................................................................106 Macrophytes......................................................................................................106 Water Quality of Surface Inflows and Outflows ..............................................................109 Trophic State.....................................................................................................................110 Use-Support Analysis.......................................................................................................116 Definition ..................................................................................................................116 Use-Support Analysis for Lake Vermilion ...............................................................119 Sediment Characteristics...................................................................................................119