Building Better Communities: A Municipal Responsibility.

Building Better Communities:

A Municipal Responsibility

Building Better Communities:A Municipal Responsibility

Your Local Soil and Water Conservation District

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.

Building Better CommunitiesA Municipal Responsibility


• 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

Soil Erosion and Sediment Control We Are All Connected!

Graphics credit: Kane-DuPage SWCD

Why Should You Be Concerned?

• It’s the law. • Soil erosion and

sediment control is required by:

Federal regulationsState lawsLocal ordinances

Photo credit SWCD of Lake County


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


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


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


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


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

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

Raindrop Erosion

This is where it starts• Rain drops act as bombs

They dislodge soil particles and allow for transport

Photo credit USDA NRCS

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

Rill and Gully Erosion

• Rill and Gully erosion occurs after runoff flows concentrate into rivulets, cutting into the soil surface.


Streambank and Bed Erosion

• Streambank and bed erosion occurs with an increase in the volume and velocity of runoff.


Wind Erosion

• Wind erosion may occur on any soil whose surface is dry and unprotected by vegetation.


Factors Influencing Erosion

• Soils

• Surface Cover

• Topography

• Rainfall Intensity

Photo credit Lake SWCD

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.


• Plan the site to fit its natural characteristics.

TopographySoilDrainage patternsExisting vegetation Photo credit Green Book Slide Set


• Preserve and protect areas of existing vegetation.

Photo credit Green Book Slide Set


• 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.

Photo credit NRCS Plainfield


• Install sediment control and perimeter 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.

Sequencing of SE/SC

1. Install all runoff and sediment control practices around the perimeter of the site.

2. Install and stabilize construction entrance(s). 3. Install and stabilize stormwater management

facilities.4. Seed within 7 days (temporary or permanent).5. Phase the plan in workable units in a construction

sequence so that only the area actively being developed is exposed.

Sequencing of SE/SC

6. Seed both temporary and permanent vegetation to all appropriate areas, including soil stockpiles and disturbed areas.

7. Stabilize all channels adequately (with channel lining and outlet protection).

8. Take measures to address dust control as needed (stabilize with seed and water spraying trucks).

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.

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.

Soil Erosion Sediment Control BMP Selection Process

Step 1 – Identify the control problem

• Sediment control

• Runoff control

• Soil stabilization


Step 2 – Identify the problem areas

• Large areas (>1 acre)

• Small areas (<1 acre)

• Drainageways

• Graded areas

• Slopes


Step 3 – Identify the required strategy

• Protect the surface

• Manage surface water

• Divert runoff

• Convey runoff

• Trap sediment

• Filter sediment


Step 4 – Identify the control measure group

• Vegetative soil cover

• Non-vegetative soil cover

• Diversions

• Waterways

• Sediment basins/traps

• Sediment filters


Step 5 – Select and implement the specific control measure such as:

• Temporary seeding• Permanent seeding• Mulching• Silt fence• Sediment basin• Grass swale• Diversion

Soil Erosion and Sediment Control BMP Guide

Soil Stabilization BMPs

• Mulching

• Erosion Blanket

• Temporary Seeding

• Permanent Seeding

• Sodding

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.


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.



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

Permanent Seeding

• This practice establishes permanent vegetative cover to stabilize disturbed areas.

• Its purpose is to reduce erosion and decrease sediment.



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.


Runoff Control BMPs

• Rock Check Dams

• Temporary Diversions

• Temporary Swales

• Temporary Slope Drain

• Diversion

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.



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.


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.


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

Diversion

• It is a channel and supporting ridge constructed across the slope to collect and divert runoff.

• Its purpose is to divert excess water from one area for use or safe disposal in other areas.


Sediment Control BMPs

• Silt Fence

• Stabilized Construction Entrance

• Temporary Sediment Trap

• Temporary Sediment Basin

• Inlet Protection

• Dewatering Devices

Silt Fence

• It is a temporary, entrenched barrier of geotextile fabric attached to posts.

• Its purpose is to intercept sediment laden water from small drainage areas and cause deposition of sediment from SHEET flows.

Photo credit SWCD of Lake Co.

Stabilized Construction Entrance

• A stabilized construction entrance is a pad of aggregate over filter fabric located at any point where construction traffic enters/exits construction areas.

• Its purpose is to reduce or eliminate tracking of sediment onto public right-of-ways.



Temporary Sediment Trap

• A temporary sediment trap is a small ponding basin formed by excavation or berm.

• Its purpose is to detain sediment laden water from disturbed areas.


Temporary Sediment Basin

• It is a basin constructed to collect and store debris and sediment.

• Its purposes are to trap sediment originating from constructions sites and to prevent undesirable deposition.



Inlet Protection-Straw Bale

• Inlet protection is a temporary straw bale barrier around a drop inlet.

• Its purpose is to prevent sediment from entering storm drains.


Inlet Protection-Fabric Drop

• It is a temporary fabric barrier placed around a drop inlet.

• Its purpose is to prevent sediment-laden water from entering the storm sewer system.



Inlet Protection-Block and Gravel

• It is a temporary sediment control barrier formed around a storm drain inlet by the use of concrete blocks and gravel.

• Its purpose is to help prevent sediment from entering storm drains before the watershed is stabilized.

Photo credit NC Erosion and Sediment Control Planning and Design Manual

Inlet Protection-Gravel and Wire Mesh

• It is a temporary sediment control barrier formed around a storm drain inlet by the use of gravel and wire mesh.

• Its purpose is to help prevent sediment from entering storm drains before stabilizing the site.

Photo credit MN Protecting Water Quality

in Urban Areas

Dewatering Devices

• These are designed to route sediment laden stormwater to a sediment filtering device prior to its leaving the site.

• Their purposes are to remove groundwater or collected surface water from a site without causing negative effects offsite.


Photo credit McHenry County SWCD

Other SE/SC BMPs• Dust Control prevents dust

blowing and movement on construction sites and roads.

• Its purposes are to prevent blowing and movement of dust from exposed soil surfaces, to reduce on and off-site damage, to minimize health hazards and to improve traffic safety.


Other SE/SC BMPs• Temporary Stream Crossing

is a temporary structure installed across a stream or watercourse for short-term use by construction vehicles.

• Its purpose is to provide a means for construction vehicles to cross streams without moving sediment into streams, damaging the streambed, or causing flooding. Photo credit Kane-DuPage SWCD

Soil Erosion and Sediment Control Regulatory Realities

• Federal Clean Water Act-National Pollutant Discharge Elimination System Phase II (NPDES, USEPA)

• Total Maximum Daily Loads (TMDLs, USEPA)

• Illinois State Erosion and Sediment Control Guidelines

• County and Municipal Ordinances

Regulatory RealitiesNPDES Phase II

Small Construction Site Program• Applies to all construction sites greater than 1

acre statewide.• Requires a stormwater pollution prevention

plan that addresses SE/SC and construction site waste.

• Requires submittal of a notice of intent (NOI) and notice of termination (NOT) to IEPA.


Small Municipal Separate Storm Sewer System (MS4)

• Applies to “urbanized” areas around the state.

• Participant must own or manage separate storm sewers that include grass swales, road ditches and underground storm sewers.


Who is affected?

Municipalities having more than 10,000 in population and/or areas having a population density of greater than 1,000 people/square mile.

Regulatory RealitiesNPDES Phase II – Small MS4

Minimum Control Measures

• Public Education and Outreach

• Public Participation and Involvement

• Illicit Discharge Detection and Elimination

• Construction Site Runoff Control

• Post-Construction Runoff Control

• Pollution Prevention and Good Housekeeping


Construction Site Runoff Control What is required?

1. Establish an ordinance covering SE/SC and other construction site waste.

2. Develop and implement procedures for site plan review.

3. Develop and implement procedures for site inspections and enforcement.

4. Have sanctions to ensure compliance.5. Allow for public information.6. Determine appropriate BMPs and measurable goals.

Training and Assistance

• Soil and Water Conservation District of Lake County www.lakeswcd.org

• Natural Resources Conservation Service

• Illinois EPA

• Northeastern Illinois Planning Commission

• International Erosion Control Association

• Others

http://www.lakeswcd.org/

Resources

• IL Urban Manual CD

• Procedures and Standards for Urban Soil Erosion and Sedimentation Control (Green Book)

Resources

• Field Manual for Implementation and Inspection of Erosion and Sedimentation Control Plans

• Model Ordinances


• For additional information on NPDES Phase II abd TMDLs contact:

- IEPA Bureau of Water 217-782-3362

- www.epa.state.il.us/water/index.html

• Your local Soil and Water Conservation District

- Lake County SWCD 847-223-1056

- www.lakeswcd.org

http://www.epa.state.il.us/water/index.html

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, sex, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at 202-720-2600 (voice and TDD).

To file a complaint of discrimination write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, 14th and Independence Avenue, SW, Washington, DC 20250-9410 or call 202-720-5964 (voice or TDD). USDA is an equal opportunity provider and employer.

Equal Opportunity Provider and Employer

Building Better Communities: A Municipal Responsibility.

Documents

sheet erosion sheet

raindrop erosion

proper soil erosion

types of erosion

erosion sediment deposition

gully erosion rill

construction site erosion

bed erosion strea