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Erosion & Sediment Control Workshop Erosion and Sediment ...Erosion & Sediment Control Workshop...

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Oklahoma DOT E&SC Workshop June 13, 2016 Module 1: E&SC Fundamentals 1 Erosion & Sediment Control Workshop Erosion and Sediment Control Fundamentals Erosion & Sediment Control Workshop Erosion and Sediment Control Manage the following – Communication – Work – Water – Erosion – Sediment …..in that order! “Five Pillars” - Barry Fagan, PE; Alabama DOT Erosion & Sediment Control Workshop Communication “The Best Management Practice” – External Communication – Internal Communication – Contractor Communication
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Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 1

Erosion & Sediment Control Workshop

Erosion and Sediment Control Fundamentals

Erosion & Sediment Control Workshop

Erosion and Sediment Control

• Manage the following– Communication– Work– Water– Erosion– Sediment

…..in that order!“Five Pillars” - Barry Fagan, PE; Alabama DOT

Erosion & Sediment Control Workshop

Communication

• “The Best Management Practice”

– External Communication– Internal Communication– Contractor Communication

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 2

Erosion & Sediment Control Workshop

Work

• “Inspect what you expect.”– Contractor still works for client.– Does contract adherence = compliance?– All responsibilities

should be on thetable.

Erosion & Sediment Control Workshop

Water

• “clean water in, clean water out”– Manage

• Raindrop• Runoff• Run on• Flow - through• Dewatering

Erosion & Sediment Control Workshop

Erosion

• Raindrop impact and shear forces from runoff must be minimized –cover it up and slow it down.

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 3

Erosion & Sediment Control Workshop

Sediment

• Fast water carries more sediment than slow water. If you can’t keep it, slow it down.

Erosion & Sediment Control Workshop

Exercise

• What are the five pillars of erosion and sediment control management and provide in the correct order of importance?

Erosion & Sediment Control Workshop

Operational BMPs• Follow the SW/E&SC Plan• Re-emphasize protection of critical areas• Minimize amount and duration of exposure • Inventory materials• Implement concurrent with clearing and

grubbing• Implement in phases (clearing/grubbing

and mass grading)• Good housekeeping• Maintain BMP measures

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 4

Erosion & Sediment Control Workshop

Sediment Losses by System

100

25 3 0 0

400

100

300.4 0.5

050

100150200250300350400450

Const

ruct

ion

Row C

rop

Crop

Rotat

ion

Grass

Fore

st

Annual Loss (cubic

yards/acre)

Low High

NCSU Soil ScienceR. A. McLaughlin

Erosion & Sediment Control Workshop

Erosion and Sedimentation Defined

•Erosion is the wearing away of soil caused by the action of water, wind, ice, gravity or other geological agents.

•Sedimentation is the deposition of that eroded soil

*Source: NCDENR Erosion and Sediment Control Planning and Design Manual

Erosion & Sediment Control Workshop

Soil Erosion: Two Phases

• Detachment: individual particles are loosened from the soil mass.

– Rainsplash > running water > wind

• Transport: water or wind carries the detached particles downslope or downwind.

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 5

Erosion & Sediment Control Workshop

After Soil is Saturated …

Transport

Detachment

Erosion & Sediment Control Workshop

Soil Particle Size

Sand

Silt

Clay

-Large, heavy particle-Hard to detach-Quick to settle

-Size between sand and clay -Most easily eroded particle-Settleable, with time

-Hard to detach due to cohesion

-Hard to settle due to small size

Erosion & Sediment Control Workshop

Sedimentation: Size Matters

0.01

0.1

1

10

100

1000

0 0.01 0.02 0.03 0.04 0.05 0.06 0.07

Size (mm)

Sett

ling

Tim

e (h

ours

)

Fine sand

Silt

Coarse Clay

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 6

Erosion & Sediment Control Workshop

Turbidity

• Turbidity is the measure of relative water clarity

• Measured in NTU’s –Nephelometric Turbidity Units

Photo from James G. Carver,

Department of Geography and Geology,

University of South Alabama

Erosion & Sediment Control Workshop

• 50 NTU* for regular streams• 25 NTU for lakes and reservoirs• 10 NTU for trout waters

10 NTU50 NTU 0 NTU25 NTU100 NTU1,000 NTU

*NTU = Nephelometric Turbidity Unit

Erosion & Sediment Control Workshop

Before Stabilization

After Stabilization

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 7

Erosion & Sediment Control Workshop

Erosion: Bare vs. Grass*

337

4

153

20

50100150200250300350

Erosion (T/Ac/yr)

50% Slope 20% Slope

Bare SoilGrass

Erosion & Sediment Control Workshop

Before Stabilization...

Erosion & Sediment Control Workshop

…and After

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 8

Erosion & Sediment Control Workshop

Review Questions

• In general, erosion (increases/decreases) with increasing rainfall and (increases/decreases) with increasing vegetative cover.

• List general soil types (clays, silts, sands, gravel) in order from most erodible to least erodible.

Erosion & Sediment Control WorkshopConstruction SiteFocus Areas

• Gravel Construction Entrance• Silt Fence on perimeter• Managing site runoff• Protect I/O of pipes/culverts• Constructing stable slopes• Quick Groundcover• Higest protection near streams• Keep mud on your property

Erosion & Sediment Control Workshop

Gravel Construction Pads

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 9

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 10

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Review Questions

• What is the primary purpose of a gravel construction entrance?

• Your construction entrance has to be sweetened daily due to unstable base material. A cost effective solution is…?

Erosion & Sediment Control Workshop

Summary• Install at beginning of job• Maintain for effectiveness

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 11

Erosion & Sediment Control Workshop

Perimeter Protection

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Review Questions

• Good erosion control results in good sediment control. T/F and why?

• Good sediment control results in good erosion control. T/F and why?

• Silt fences are very effective sediment control practice when used in concentrated flows such as ditch lines or culvert inlet? T/F and why?

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 12

Erosion & Sediment Control Workshop

Summary

• Perimeter protection• Avoid concentrated flow• Maintain after rainfall

Erosion & Sediment Control Workshop

Managing Runoff

Erosion & Sediment Control Workshop

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 13

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Review Questions

• Bale barriers are an effective method for sediment control? Why?

• Implementing erosion control methods while road construction activities are occurring is not cost effective. T/F and why?

Erosion & Sediment Control Workshop

Summary• Plan for sediment

control at discharges• Use velocity control• Stabilize quickly

w/correct erosion control materials

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 14

Erosion & Sediment Control Workshop

Protecting Pipe Culverts and Swales

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 15

Erosion & Sediment Control Workshop

Review Questions

• What are some other stabilization materials that can substitute just as effectively and could be more economical in drainage swales/ditches instead of rip rap?

• My ditch is just a little too steep to be stabilized with seeding and mulching alone; what my next best selection?

Erosion & Sediment Control Workshop

Summary• Stabilize pipe inlets and

outlets • Perform as soon as pipe

is installed• Hard armor for swales

w/steep gradients

Erosion & Sediment Control Workshop

Constructing Stable Slopes

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 16

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Review Questions

• What two topographic factors have the greatest impact on the magnitude of erosion?

• What are some of the factors that contribute to roadway fill sloughing?

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 17

Erosion & Sediment Control Workshop

Summary• Compaction in lifts• Construct at angle that

can be stabilized w/matting and vegetation

• Stabilize in stages

Erosion & Sediment Control Workshop

Timely Groundcover

Erosion & Sediment Control Workshop

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 18

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Review Questions

• What BMP can reduce erosion up to 90-95% on disturbed sites?

• I have a one-half mile haul road through rolling topography; what is a simple construction method to minimize sediment loss?

Erosion & Sediment Control Workshop

Review Questions

• What BMP can reduce erosion up to 90-95% on disturbed sites?– Groundcover

• I have a one-half mile haul road through rolling topography; what is a simple construction method to minimize sediment loss?– Construct and stabilize in phases

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 19

Erosion & Sediment Control Workshop

Summary• As soon as grading

completed or after any phase of idle activity

• Good site prep and seed bed prep

• Attention to detail on seeding/hydroseeding

Erosion & Sediment Control Workshop

Stream Buffers

Erosion & Sediment Control Workshop

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 20

Erosion & Sediment Control Workshop

Summary• Observe buffers and

setbacks• Provide highest level of

protection• Monitor these high risk

areas for needed maintenance

Erosion & Sediment Control Workshop

Access Roads

Erosion & Sediment Control Workshop

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 21

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 22

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Review Questions

• Most construction site erosion will result fromr____________ and r___________?

• Erosion is the displacement of soil particles by the actions of w_________ and w__________?

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 23

Erosion & Sediment Control Workshop

Review Questions

• What BMP can reduce erosion up to 90-95% on construction projects?

• I have a one-half mile haul road through rolling topography; what is a simple construction method to minimize sediment loss?

Erosion & Sediment Control Workshop

Summary

• Get to know the property

• Planning critical• Follow design guidelines• Construct and stabilize

Erosion & Sediment Control Workshop

Finished Product

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 24

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Erosion & Sediment Control Workshop

Review Questions

• This addition to sediment impoundment measures greatly improves trapping efficiency?

• My project is being built near and drains to several high quality streams. What BMP or treatment can I use to minimize water quality impacts from my stormwater runoff ?

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 25

Erosion & Sediment Control WorkshopErosion and Sediment Control BMP Summary Questions

• BMPs for controlling surface water runoff

• BMPs for outlet/discharge points

• BMPs for controlling velocity in ditch lines

• BMPs for use at stream crossings

• BMPs for tie ins at public roads

Erosion & Sediment Control WorkshopErosion and Sediment Control BMP Summary Questions

• BMPs for controlling surface water runoff– berms, diversions, slope drains, level spreaders

• BMPs for outlet/discharge points– Pits, basins, wattles, rock dams

• BMPs for controlling velocity in ditch lines– Wattles, rock check dams, ditch blocks

• BMPs for use at stream crossings– Silt fence, rip rap aprons

• BMPs for tie ins at public roads– Construction entrance pads

Erosion & Sediment Control Workshop

Summary

• Follow the plans and permits

• Ask questions if needed• Be proactive!

Oklahoma DOT E&SC Workshop June 13, 2016

Module 1: E&SC Fundamentals 26

Erosion & Sediment Control Workshop

Questions?


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