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Florida Stormwater Erosion and Sediment Control Inspector's Manual

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Florida Stormwater Erosion and Sediment Control Inspector's Manual FLORIDA STORMWATER EROSION AND SEDIMENTATION CONTROL INSPECTOR’S MANUAL Florida Department of Environmental Protection Nonpoint Source Management Section Tallahassee, Florida July 2008 This publication was funded in part by the Florida Department of Environmental Protection with a Section 319 Nonpoint Source Management Program Grant from U.S. Environmental Protection Agency. i ii CONTENTS LIST OF ACRONYMS AND ABBREVIATIONS ....................................................IX INTRODUCTION....................................................................................................XI Purpose and Contents xi CHAPTER 1: EROSION AND SEDIMENTATION ................................................. 1 1.1 The Erosion Process 1 1.2 Types of Water Erosion 2 1.3 Factors Influencing Erosion 2 1.4 Impacts of Erosion and Sedimentation 4 1.5 Erosion and Sediment Hazards Associated with Land Development 5 1.6 Principles of Erosion and Sediment Control 6 CHAPTER 2: SOILS .............................................................................................. 9 2.1 Introduction to Soils 9 2.2 Soil Classification and Properties 10 2.3 Soil Surveys 15 CHAPTER 3: REGULATIONS AND STATUTORY REQUIREMENTS ............... 17 3.1 Introduction 17 3.2 NPDES Stormwater Permitting Regulations and Statutory Requirements 19 3.3 Construction Stormwater Pollution Prevention Plan Template 25 CHAPTER 4: BEST MANAGEMENT PRACTICES FOR EROSION AND SEDIMENTATION CONTROL....................................................... 33 4.1 Construction Sequencing 33 4.2 Pollution Source Controls on Construction Sites 36 4.3 Stabilized Construction Exit 39 4.4 Perimeter Controls 44 4.5 Storm Drain Inlet Protection 75 4.6 Temporary Sediment Trap 95 CHAPTER 5: BEST MANAGEMENT PRACTICES FOR DEWATERING OPERATIONS ............................................................................. 125 5.1 Introduction 125 5.2 Limitations 127 5.3 Implementation 127 5.4 Inspection and Maintenance 128 iii CHAPTER 6: BEST MANAGEMENT PRACTICES FOR STORMWATER MANAGEMENT ........................................................................... 147 6.1 Introduction 147 6.2 Earthwork Specifications 149 6.3 Stormwater Retention Basin 150 6.4 Exfiltration Trench 153 6.5 Porous Pavement 163 6.6 Concrete Grid and Modular Pavement 165 6.7 Stormwater Detention Basin 167 6.8 Underdrain and Filtration Systems 171 6.9 Swales 177 6.10 Stormwater Conveyance Channel 182 6.11 Paved Flume 186 6.12 Diversion 188 6.13 Check Dam 192 6.14 Outlet Protection 194 6.15 Riprap 199 6.16 Grid Confinement System 203 6.17 Cellular Concrete Block 206 6.18 Maintenance 211 CHAPTER 7: BEST MANAGEMENT PRACTICES—VEGETATION FOR EROSION CONTROL.................................................................. 221 7.1 Introduction 221 7.2 Surface Roughening 221 7.3 Topsoiling 227 7.4 Temporary Seeding 229 7.5 Permanent Seeding 231 7.6 Sodding 235 7.7 Mulching 241 7.9 Tree Preservation and Protection 263 7.10 Vegetative Streambank Stabilization 271 CHAPTER 8: THE EROSION AND SEDIMENT CONTROL PLAN................... 279 8.1 Introduction 279 8.2 Elements of the Erosion and Sediment Control Plan 279 8.3 Implementing the Erosion and Sediment Control Plan 281 iv CHAPTER 9: INSPECTION AND ENFORCEMENT.......................................... 285 9.1 Introduction 285 9.2 The Role of the Inspector 285 9.3 Site Inspection 287 9.4 Regulatory Agencies 295 REFERENCES.................................................................................................... 315 LIST OF TABLES Table 2.1. USDA Particle Size Classes ........................................................................11 Table 2.2. USDA Soil Permeability Classes .................................................................13 Table 4.1. Size of Slope Drain ......................................................................................61 Table 4.2. Minimum Top Width (W) and Outlet Height (Ho) Required for Sediment Trap Embankment According to Height of Embankment (feet) ............................................................................................................96 Table 4.3. Minimum Pipe Diameter for Pipe Outlet Sediment Trap According to Maximum Size of Drainage Area .................................................................97 Table 5.1. Comparison of Dewatering Technologies..................................................126 Table 6.1. Grass Establishment Alternatives..............................................................180 Table 7.1. Organic Mulch Materials and Application Rates ........................................242 Table 7.2. Conditions Where Vegetative Streambank Stabilization Is Acceptable .................................................................................................274 LIST OF FIGURES Figure 2.2. Guide to the Textural Classification of Soils ________________________11 Figure 4.3a. Temporary Gravel Construction Entrance _________________________41 Figure 4.3b. Soil Tracking Prevention Device_________________________________42 Figure 4.3c. Construction Entrance with Wash Rack ___________________________43 Figure 4.4a. Silt Fence __________________________________________________47 Figure 4.4b. Installing a Filter Fabric Silt Fence _______________________________48 Figure 4.4c. Double Row Staked Silt Fence __________________________________50 Figure 4.4d. Proper Placement of a Silt Fence at the Toe of a Slope_______________50 Figure 4.4e. Temporary Diversion Berm_____________________________________55 Figure 4.4f. Temporary Fill Diversion_______________________________________57 Figure 4.4g. Overside Drain ______________________________________________60 Figure 4.4h. Flared End Section Schematic __________________________________61 Figure 4.4i. Flared End Section Specifications _______________________________62 Figure 4.4j. Temporary Slope Drain________________________________________64 Figure 4.4k. Slope Drain _________________________________________________65 Figure 4.4l. Type I and II Floating Turbidity Barriers ___________________________70 v Figure 4.4m. Type III Floating Turbidity Barrier ________________________________71 Figure 4.4n. Typical Installation Layouts_____________________________________72 Figure 4.5a. Silt Fence Drop Inlet Sediment Barrier ____________________________77 Figure 4.5b. Filter Fabric Drop Inlet Sediment Filter ____________________________78 Figure 4.5c. Gravel and Wire Mesh Drop Inlet Sediment Filter ___________________80 Figure 4.5d. Block and Gravel Drop Inlet Sediment Filter________________________81 Figure 4.5e. Gravel Filters for Area Inlets ____________________________________84 Figure 4.5f. Sod Drop Inlet Sediment Filter __________________________________85 Figure 4.5g. Gravel Curb Inlet Sediment Filter ________________________________87 Figure 4.5h. Gravel Curb Inlet Sediment Filter with Overflow Weir_________________88 Figure 4.5i. Block and Gravel Curb Inlet Sediment Barrier ______________________89 Figure 4.5j. Curb Inlet Gravel Filters _______________________________________90 Figure 4.5k. Curb Inlet Sediment Barrier ____________________________________92 Figure 4.5l. Gravel Bag Curb Sediment Filters _______________________________93 Figure 4.5m. Curb and Gutter Sediment Barrier _______________________________94 Figure 4.6a. Earth Outlet Sediment Trap ____________________________________98 Figure 4.6b. Pipe Outlet Sediment Trap _____________________________________99 Figure 4.6c. Stone Outlet Sediment Trap ___________________________________101 Figure 4.6e. Excavated Drop Inlet Sediment Trap ____________________________102 Figure 4.6f. Storm Inlet Sediment Trap ____________________________________103 Figure 4.6g. Small Sediment Trap Located in a Stormwater Conveyance Channel __________________________________________________104 Figure 4.6h. Sediment Containment Filter Bag_______________________________105 Figure 4.7a. Sediment Basin Storage Volumes ______________________________107 Figure 4.7b. Sample Plan View of Baffle Locations in Sediment Basins ___________108 Figure 4.7c. Sediment Basin Schematic Elevations ___________________________110 Figure 4.7d. Antivortex Device Design _____________________________________112 Figure 4.7e. Riser Pipe Conditions ________________________________________113 Figure 4.7f. Location of Anti-seep Collars __________________________________114 Figure 4.7g. Emergency Spillway _________________________________________114 Figure 4.7h. Sediment Basin_____________________________________________115 Figure 4.8a. Rock Check Dam ___________________________________________121 Figure 4.8b. Rock Check Dam Details _____________________________________122 Figure 5.4. Dewatering Operations Flow Chart______________________________129 Figure 6.3a. Off-Line Treatment Systems___________________________________151 Figure 6.3b. Schematic of Flow Characteristics Associated with Infiltration from Retention Ponds during Low and High Water Table Conditions________152 Figure 6.4a. Cross-Section of Typical Infiltration/Exfiltration System for Parking or Roads __________________________________________________154 Figure 6.4b. Sample Application of a Vegetated Area for Pretreatment of Runoff Prior to Exfiltration in Frederick County, Maryland __________________155 vi Figure 6.4c. Examples of Typical Underground Percolation Systems for Retrofitting Existing Storm Sewer Systems in Orlando, Florida ________159 Figure 6.4d. Detailed Schematic of a Typical Observation Well __________________161 Figure 6.5. Examples of Porous Pavement
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