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Building Better Communities:

Building Better Communities:. A Municipal Responsibility. Building Better Communities: A Municipal Responsibility. Your Local Soil and Water Conservation District. Building Better Communities A Municipal Responsibility. Soil Erosion and Sediment Control

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Building Better Communities:

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  1. Building Better Communities: A Municipal Responsibility

  2. Building Better Communities:A Municipal Responsibility Your Local Soil and Water Conservation District

  3. Building Better CommunitiesA Municipal Responsibility Soil Erosion and Sediment Control The practice of preventing the movement of soil and sediment from its original position on the landscape during and after development.

  4. Soil Erosion and Sediment Control • To understand how we impact and are impacted by water, the concept of the water cycle is key Graphics credit: Delaware Dept. of Natural Resources

  5. Soil Erosion and Sediment Control We Are All Connected! Graphics credit: Kane-DuPage SWCD

  6. Why Should You Be Concerned? • It’s the law. • Soil erosion and sediment control is required by: • Federal regulations • State laws • Local ordinances Photo credit SWCD of Lake County

  7. Why Should You Be Concerned? Construction Sites • Soil erosion from a construction site without proper soil erosion and sediment control practices in place can average between 20-200 tons/acre/year. This is 10 to 20 times greater than the typical soil losses on agricultural lands. Photo credit NRCS Bourbonnais

  8. Why Should You Be Concerned? Surface Water Quality: • Nearly 45% of Illinois streams and more than 75% of lake acres assessed have been adversely impacted by nonpoint source pollutants. • Urban runoff and construction site erosion have been identified as significant sources of this pollution. Photo credit Kane-DuPage SWCD

  9. Why Should You Be Concerned? Fish and Aquatic Organisms • Sediment deposits destroy fish spawning areas resulting in the loss of sensitive or threatened fish species. • Suspended solids cause serious damage to aquatic life. Photo credit Kane–DuPage SWCD

  10. Why Should You Be Concerned? Chemical Pollutants • Chemicals such as pesticides, phosphorus, as well as toxicants and trace metals can be transported with sediment to receiving waters where they cause additional damage to aquatic ecosystems. Photo credit USDA NRCS

  11. Why Should You Be Concerned? Damage to Wetlands and Aquatic Plants • Approximately 70% of permitted sites show evidence of sediment accumulation resulting from erosion • Sediment deposition of less than .1 inch results in a 60-90% decrease in wetland seed germination from new seedings or from wetland seed banks • Decreased species diversity • Increase in undesirable species

  12. Types of Erosion 1. Raindrop erosion 2. Sheet erosion 3. Rill and gully erosion 4. Streambank and bed erosion 5. Wind erosion Graphics credit IL Urban Manual

  13. Raindrop Erosion This is where it starts • Rain drops act as bombs • They dislodge soil particles and allow for transport Photo credit USDA NRCS

  14. Sheet Erosion • Sheet erosion is the removal of a layer of exposed soil by the action of raindrop splash and runoff. • The water moves in broad sheets over the land and is not confined in concentrated flow paths. Photo credit NRCS Bourbonnais

  15. Rill and Gully Erosion • Rill and Gully erosion occurs after runoff flows concentrate into rivulets, cutting into the soil surface. Photo credit Kane-DuPage SWCD

  16. Streambank and Bed Erosion • Streambank and bed erosion occurs with an increase in the volume and velocity of runoff. Photo credit Kane-DuPage SWCD

  17. Wind Erosion • Wind erosion may occur on any soil whose surface is dry and unprotected by vegetation. Photo credit Kane-DuPage SWCD

  18. Factors Influencing Erosion • Soils • Surface Cover • Topography • Rainfall Intensity Photo credit Lake SWCD

  19. Principles of Soil Erosion and Sediment Control • Plan the site to fit its natural characteristics. • Preserve and protect areas of existing vegetation. • Take special precautions to prevent damages to adjacent watercourses, lakes, and wetlands. • Minimize the extent and duration of the area exposed at one time. • Apply temporary erosion control practices as soon as possible to stabilize exposed soils and prevent onsite damage. • Install perimeter control and sediment control practices prior to site clearing and grading. • Minimize runoff velocities and retain runoff on the site. • Install measures to prevent sediment from being tracked onto public or private roadways. • Complete final grading and install permanent vegetation on disturbed areas. • Conduct thorough inspection, maintenance, and follow-up programs.

  20. Principles of Soil Erosion and Sediment Control • Plan the site to fit its natural characteristics. • Topography • Soil • Drainage patterns • Existing vegetation Photo credit Green Book Slide Set

  21. Principles of Soil Erosion and Sediment Control • Preserve and protect areas of existing vegetation. Photo credit Green Book Slide Set

  22. Principles of Soil Erosion and Sediment Control • Take special precautions to prevent damages to adjacent watercourses, lakes, and wetlands. Photo credit Kane-DuPage SWCD

  23. Principles of Soil Erosion and Sediment Control • Minimize the extent and duration of the area exposed at one time. Photo credit Kane-DuPage SWCD

  24. Principles of Soil Erosion and Sediment Control • Apply temporary erosion control practices as soon as possible to stabilize exposed soils and prevent onsite damage. Photo credit NRCS Plainfield

  25. Principles of Soil Erosion and Sediment Control • Install sediment control and perimeter control practices prior to site clearing and grading. Photo credit NRCS Plainfield

  26. Principles of Soil Erosion and Sediment Control • Minimize runoff velocities and retain runoff on the site. Photo credit Kane-DuPage SWCD

  27. Principles of Soil Erosion and Sediment Control • Install measures to prevent sediment from being tracked onto public or private roadways. Photo credit NRCS Plainfield

  28. Principles of Soil Erosion and Sediment Control • Complete final grading and install permanent vegetation on disturbed areas. Photo credit NRCS Plainfield

  29. Principles of Soil Erosion and Sediment Control • Conduct thorough inspection, maintenance, and follow-up programs.

  30. Sequencing of SE/SC • Install all runoff and sediment control practices around the perimeter of the site. • Install and stabilize construction entrance(s). • Install and stabilize stormwater management facilities. • Seed within 7 days (temporary or permanent). • Phase the plan in workable units in a construction sequence so that only the area actively being developed is exposed.

  31. Sequencing of SE/SC • Seed both temporary and permanent vegetation to all appropriate areas, including soil stockpiles and disturbed areas. • Stabilize all channels adequately (with channel lining and outlet protection). • Take measures to address dust control as needed (stabilize with seed and water spraying trucks).

  32. Inspection • At a minimum, inspect BMPs every 7 days or after a 0.5 inch rain event or event or equivalent snowfall. • Inspect BMPs daily during prolonged rain events. • Conduct annual inspections for permanent stormwater management BMPs.

  33. Maintenance • Apply maintenance continually to all soil erosion and sediment control measures until the site is stabilized. • When the time is appropriate, all temporary control structures that are no longer necessary will need to be removed. Also, all control structure repairs and sediment removal will need to be done.

  34. Soil Erosion Sediment Control BMP Selection Process Step 1 – Identify the control problem • Sediment control • Runoff control • Soil stabilization

  35. Soil Erosion Sediment Control BMP Selection Process Step 2 – Identify the problem areas • Large areas (>1 acre) • Small areas (<1 acre) • Drainageways • Graded areas • Slopes

  36. Soil Erosion Sediment Control BMP Selection Process Step 3 – Identify the required strategy • Protect the surface • Manage surface water • Divert runoff • Convey runoff • Trap sediment • Filter sediment

  37. Soil Erosion Sediment Control BMP Selection Process Step 4 – Identify the control measure group • Vegetative soil cover • Non-vegetative soil cover • Diversions • Waterways • Sediment basins/traps • Sediment filters

  38. Soil Erosion Sediment Control BMP Selection Process Step 5 – Select and implement the specific control measure such as: • Temporary seeding • Permanent seeding • Mulching • Silt fence • Sediment basin • Grass swale • Diversion

  39. Soil Erosion and Sediment Control BMP Guide

  40. Soil Stabilization BMPs • Mulching • Erosion Blanket • Temporary Seeding • Permanent Seeding • Sodding

  41. Mulching • It is the application of plant residues and other suitable materials to the soil surface. • Its purposes are to prevent erosion and surface compaction by protecting soil surface from raindrop impact and reducing the velocity of overland flow. Photo credit Green Book Slide Set

  42. Erosion Blanket • It is a protective blanket of straw or other plant residue, usually with a plastic mesh on one or both sides. • The purposes are to protect the soil from raindrop erosion and overland flows during the establishment of vegetation. Photo credit NRCS Plainfield Photo credit Kane-DuPage SWCD

  43. Temporary Seeding • This practice stabilizes the soil using fast growing vegetation. • Its purposes are to stabilize the soil within 7 days and to reduce sediment until permanently stabilized. Photo credit North Cook SWCD Photo credit NRCS Plainfield

  44. Permanent Seeding • This practice establishes permanent vegetative cover to stabilize disturbed areas. • Its purpose is to reduce erosion and decrease sediment. Photo credit North Cook SWCD Photo credit NRCS Plainfield

  45. Sodding • It stabilizes fine-graded disturbed areas by laying a continuous cover of grass sod. • Its purposes are to prevent erosion and sedimentation, improve visual quality, and allows for immediate use. Photo credit NRCS Plainfield

  46. Runoff Control BMPs • Rock Check Dams • Temporary Diversions • Temporary Swales • Temporary Slope Drain • Diversion

  47. Rock Check Dams • A small rock dam constructed across a grassed swale or road ditch. • Its purposes are to reduce the velocity of concentrated stormwater flows, reduce erosion, trap sediment, and increase infiltration. Photo credit NRCS Plainfield Photo credit North Cook SWCD

  48. Temporary Diversions • A temporary diversion is a ridge or channel across slope on the grade. • Its purpose is to direct sediment laden flows to a trapping facility or stabilized outlet. Photo credit Kane-DuPage SWCD

  49. Temporary Swale • A temporary swale is an excavated drainageway. • Its purpose is to prevent runoff from reaching disturbed areas by intercepting and diverting it to a stable outlet. Photo credit Green Book Slide Set

  50. Temporary Slope Drain • It is a flexible tubing or rigid conduit extending temporarily from the top to the bottom of a cut or fill slope. • Its purpose is to convey concentrated runoff down the face of a cut or fill slope without causing erosion on or below the slope. Photo credit North Carolina SE/SC Manual

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