Shoal Creek Watershed Assessment November 2009 Produced for: 100 S. Hill Street Griffin, GA 30224 Produced by: 2110 Powers Ferry Road SE Suite 202 Atlanta, GA 30339 Shoal Creek Watershed Assessment November 2009 Table of Contents List of Tables ............................................................................................................................. iii List of Figures ............................................................................................................................. iv Appendices ............................................................................................................................. iv 1 Executive Summary..................................................................................................................1 2 Introduction...............................................................................................................................3 3 Shoal Creek Watershed Characterization.................................................................................4 3.1 City of Griffin, Shoal Creek Watershed, and Wastewater Service Area......................................................4 3.2 Natural Features .........................................................................................................................................10 3.3 Environmentally Sensitive Areas ...............................................................................................................10 3.4 303(d) Listed Waterbodies.........................................................................................................................13 3.4.1 Biota (sediment)...................................................................................................................................13 3.4.2 Downstream Impairment .....................................................................................................................14 3.5 Significant Facilities and Activities ...........................................................................................................14 3.5.1 Water Supplies.....................................................................................................................................14 3.5.2 Wastewater and Stormwater Facilities.................................................................................................14 3.5.3 Agricultural Operations .......................................................................................................................15 3.5.4 Solid and Hazardous Waste and Toxic Releases .................................................................................15 4 Data Collection.......................................................................................................................16 4.1 Water Quality Data ....................................................................................................................................16 4.1.1 Monitoring Stations .............................................................................................................................16 4.1.2 Monitoring History ..............................................................................................................................20 4.2 Land Use Data............................................................................................................................................22 4.3 Biological/Habitat Data..............................................................................................................................26 4.3.1 2000 Biological/Habitat Data ..............................................................................................................26 4.3.2 2004/2005 Biological/Habitat Data .....................................................................................................26 4.3.3 2008/2009 Biological/Habitat Data .....................................................................................................27 4.4 Other Monitoring Data...............................................................................................................................27 4.4.1 Geomorphic Assessment......................................................................................................................27 4.4.2 Sediment Evaluation............................................................................................................................28 4.4.3 North Griffin Regional Detention Pond Water Quality Monitoring ....................................................28 i Shoal Creek Watershed Assessment November 2009 4.4.4 Oakview Detention Pond Water Quality Monitoring ..........................................................................29 4.4.5 LSPC Hydrology and Water Quality Modeling...................................................................................29 5 Data Analysis..........................................................................................................................31 5.1 Water Quality Analysis..............................................................................................................................31 5.1.1 Temperature.........................................................................................................................................32 5.1.2 Oxygen Demand ..................................................................................................................................32 5.1.3 Turbidity ..............................................................................................................................................35 5.1.4 Nutrients ..............................................................................................................................................36 5.1.5 Metals and Toxic Organic Compounds ...............................................................................................39 5.1.6 Sediment Samples................................................................................................................................43 5.1.7 Fecal Coliform.....................................................................................................................................45 5.1.8 North Griffin Regional Detention Pond...............................................................................................47 5.2 Land Use Analysis .....................................................................................................................................48 5.3 Biological Analysis ....................................................................................................................................51 5.3.1 Biological/Habitat Assessment 2000 ...................................................................................................51 5.3.2 Biological/Habitat Assessment 2004/2005 ..........................................................................................51 5.3.3 Biological/Habitat Assessment 2008/2009 ..........................................................................................53 5.3.4 Biological/Habitat Summary ...............................................................................................................54 6 Constituents & Areas of Concern...........................................................................................56 7 References .............................................................................................................................58 ii Shoal Creek Watershed Assessment November 2009 List of Tables Table 3-1. Listed Species in Spalding County......................................................................11 Table 3-2. TMDL for Wasp Creek .......................................................................................13 Table 4-1. Monitoring Stations.............................................................................................17 Table 4-2. Summary of Sampling Conducted in the Shoal Creek Watershed Since 2001...20 Table 4-3. Sample Events .....................................................................................................20 Table 4-4. Land Use Classification.......................................................................................23 Table 5-1. Consensus-Based Effect Concentrations for Pollutants in Freshwater Sediments44 Table 5-2. North Griffin Regional Detention Pond Pollutant Removal Efficiency..............48 Table 5-3. Impervious Area of Monitoring Station Subwatersheds .....................................51 Table 5-4. Summary of Biological Assessments ..................................................................54 Table 5-5. Scores for Comparable FIBI Metrics from 2005 to 2009 Assessments ..............55 iii Shoal Creek Watershed Assessment November 2009 List of Figures Figure 3-1. City of Griffin Watersheds ....................................................................................6 Figure 3-2. Shoal Creek Wastewater Service Area, Permitted Facilities, Septic Systems, and 303(d) Streams ...............................................................................................................................7 Figure 3-3. Aerial Photograph of Shoal Creek Service Area...................................................8 Figure 3-4. Topographic Map of Shoal Creek Service Area....................................................9 Figure 3-5. National Wetland Inventory Wetlands in Shoal Creek Service Area..................12