City of Idaho Falls Erosion & Sediment Control

City of Idaho FallsErosion & Sediment Control Inspector Training

Engineering with a Mission, LLCSyman Company

Goals and Objectives for Inspector Training Class:

✓To give you tools to more easily do you job of inspecting Erosion and Sediment Control BMP’s.

Agenda for This Class

History of the EPA Clean Water Act - NPDES

City of Idaho Falls - Responsibility

EPA Construction General Permit (CGP)

Erosion – Erosion Control BMP’s

Sediment – Sediment Control BMP’s

Other BMP’s – Dewatering, housekeeping

Final Stabilization

Inspection Checklist

WHY ARE WE HERE?!?!

EPA created the Clean Water Act (CWA), in part, to make sure that our rivers and lakes are:

FISHABLE&

SWIMABLE

IT’S THE LAW…

❖ The City of Idaho Fall is required to do their part to minimize the polluting of stormwater that discharges to the Snake River.

❖ Part of what the EPA requires the City to have ordinances that pertain to erosion and sediment control and to enforce those ordinances by inspection.

❖ The City doesn’t have an option but to abide by EPA’s conditions as they pertain to construction.

❖ Failure to meet these requirements is a violation of Federal Law.

Why is Water Quality Important?

Increase in Water Temp

Decrease in Aquatic Plants

Decrease in Aquatic Insects

Decrease in Food for Fish

Less Enjoyable for Recreation

When the sediment load increases, water tends to spread out over a larger area. Shallow, wide channels provide more surface area for solar energy to enter the stream, potentially increasing water temperature. In addition, turbidity raises water temperature because the suspended particles absorb the sun's heat.

So what does all this have to do with you as an inspector?

Construction is the leadingcause of sediment runoff in urban areas

Clean Water Act

National Pollution Discharge Elimination System (NPDES)

Stormwater Management

Construction Multi-Sector General

General Permit (CGP) Permit (MSGP)

Municipal Separate Storm Sewer System (MS4)

You’re working under this as an inspector for I.F.

City of Idaho Falls Construction Site Erosion Control Ordinance

Purpose:

To protect storm water, ground water, water bodies, water courses, and wetlands from construction activities pursuant to and consistent with the United States Clean Water Act.

To manage and control the amount of pollutants in storm water discharges, soil erosion, sediment discharge, and mud and dirt deposits on public roadways caused by or the result of construction activities.

Idaho Department of Environmental Quality

Responsible For:

Regulating fugitive dust emissions in Idaho.

Idaho State Rules for the Control of Air Pollution in Idaho (IDAPA 58.01.01.651) requires that all "reasonable precautions" be taken to prevent particulate matter from becoming airborne. Reasonable precautions include using water or chemical, applying dust suppressants, using control equipment, covering trucks, paving, and removing materials.

Idaho Department of Environmental Quality

Consequences of Noncompliance

Failure to reasonably control fugitive dust may result in enforcement action by DEQ, which can include monetary penalties.

Construction General Permit• The EPA administers the

CGP in Idaho

• A Permit is Required for:o For sites > 1 acre o Sites < 1 acre that are

part of a larger common plan of development

o Applicable inside and outside the City Limits!

Recap

• EPA/Clean Water Act

• City of Idaho Falls responsibilities

• Idaho Department of Environmental Quality

• EPA’s Construction General Permit (CGP)

Best Management Practices (BMP’S)

What are BMP’s?Methods, measures, or practices to prevent or reduce water pollution, including but not limited to, structural and non-structural controls, operation and maintenance procedures, and other requirements, scheduling, and distribution of activities.

Classes of BMP’s

• EROSION CONTROL

• SEDIMENT CONTROL

• RUN ON/RUNOFF CONTROL

• HOUSEKEEPING/MATERIALS MANAGEMENT

• PLANNING AND PROJECT MANAGEMENT

• POST CONSTRUCTION BMP’S

EROSIONThe detachment and movement of soil

material by the action of water or wind.

Erosion ControlFirst line of defense!

– Prevent soil from moving and you don’t have to clean it up somewhere else

– Prevent water from running across exposed slopes and surfaces

An ounce of prevention is worth a pound of cure….

What Factors Influence Erosion?

✓Soil erodibility

✓Vegetative Cover

✓Topography

✓Climate

✓Season

Erosion Controls

❖Preserving Vegetation

❖Slope Tracking/Soil Roughening

❖Mat and Blankets

❖Mulching

Preserving Vegetation

✓Preserving vegetation is the best method to prevent erosion!

✓Preserving vegetation is a FREE BMP!

✓Slows down water velocity

✓Roots hold soil in place

✓Reduces rain drop erosion

Preserving Vegetation

Erosion Control – Slope Tracking/Soil Roughening

Purpose

oHold soil in place

oTrap seeds

oReduce flow velocity

Maintenance Issues?

Erosion Control – Mats and Blankets

Purpose

oTemporary Stabilization

oEstablish Vegetation

oSpecs can differ greatly!

Erosion Control – Mat and Blankets

Proper installation is KEY

oPrepare seedbed/seed area before mats are installed

oWork from top of the slope down

oStake in well at the top and overlap sufficiently

oContact with the soil

Erosion Control – Mulching

oChek that the appropriate amount of mulch and tackifier has been applied

oApply more mulch (lbs/acre) on steep slopes

oLess mulch may be appropriate for flatter surfaces

SedimentDefinition:

Sediment is eroded material suspended in water or wind. Suspended solid material that is being moved from it’s original location.

Types Sediment Controls

❖Stabilized Construction Entrance

❖Fiber roll & straw wattles

❖Silt fence

❖Check dams

❖Inlet and outlet protection

*Generally 50% effective at best

Sediment Control – Stabilized Entrance

❖Non-negotiable – must have

❖2”-4” clean crushed rock

❖Approx. 6” thick

❖20’ wide and 50’ long

❖Must replenish if it gets mucky

Sediment Control – Stabilized Entrance

Must sweep SAME DAY as track out happens

Sediment Control – Fiber Rolls/Straw Wattle

❖Very versatile tool for Sediment Control

❖Can be used for:• Perimeter control

• Sediment Control on hillsides – at the bottom as well as along the contour

❖Primary function is to slow water down and trap sediment


❖Always Install along the contour

❖Sufficiently overlap ends where they meet

❖Requires good contact with the soil

❖Stake down every 4’


Generally not good applications for this product…..


Maintenance issues to look for…

Sediment Control – Silt Fence

A porous fabric that works by ponding water and allowing sediment to settle out

❖Good for use at the bottom of an exposed slope

❖Good as a barrier around a stockpile


Absolutely useless if installed improperly.

❖Must be trenched in

❖Stakes must be on the downhill side

Maintenance issues?


What’s wrong with this picture?

How would you direct some one fix it?

Sediment Control – Check DamsPrimary purpose is to slow the velocity of the water.

Sediment Control – Check Dams

Proper Installation is key to effectiveness

Sediment Control – Check Dams

Maintenance issues?

Sediment Control – Inlet ProtectionLAST CHANCE TO STOP SEDIMENT!

Primary purpose is to slow the velocity of the water and filter out sediment.

Sediment Control – Inlet Protection

MAINTENANCE OF THIS BMP’S IS CRITICAL!

Sediment Control – Outlet Protection

Primary function is slowing the velocity of the water

• Use clean angular rock for riprap

• Should be 4X wider than the diameter of the culvert

• Length is dependent on slope and erodibility of the receiving soil

RUN ON/RUNOFF CONTROL

Run on Management: Divert external flows from running onto the site

Run off Management: Reduce velocity of water running off to reduce sediment loss

HOUSEKEEPING/MATERIALS MANAGEMENT

❑Debris Containment

❑Dust Management

❑Storage and proper disposal of toxic material

❑Stockpile Management

❑Planning & Phasing

❑Post-Construction BMP’s


Debris Containment

New CGP states containers will be covered with not in use!!!

If dumpsters overflow they must be cleaned up immediately


Dust Management:

Why is dust regulated?

•Health risk – lung cancer, COPD, silicosis, Asthma

•Air Quality issue

•Nuisance


Dust Management BMP’s

➢Stabilize roadways

➢Water exposed areas

➢Preserve existing vegetation

➢Sweep

➢Stockpile stabilization

➢Saw cutting – use water and a vacuum


Storage and proper disposal of toxic material


Store oils properly

Use drip pans

Clean up ALL spills immediately


Storage and proper disposal of toxic material – A concrete washout is REQUIRED by the CGP – must be leak proof!


Washout rules Apply to stucco, paint, mortar, caulking, drywall

Clean up spills immediately


✓Porta potty – Needs to be staked down to protect from vandals and not placed near DI’s!

✓Keep a Spill Kit on site at all times.

✓Avoid onsite vehicle fueling and maintenance if at all possible.

✓Sweep entrance DAILY.


Illicit Discharges:

An illicit discharge is defined as any discharge to the MS4 that is not composed entirely of storm water, except for discharges allowed under a EPA permit.


Stockpile Management

If it can discharge from the site, a barrier needs to be around it.

Planning and Phasing – DewateringRead and understand the dewatering plan!

Post Construction BMP’sPost construction BMP’s include anything that stabilizes a site on a permanent basis. This can include anything that covers bare soil such as:

• Asphalt

• Concrete Paving

• Buildings

• Landscaping

Again, there should be no bare soil on the site once construction is complete. Per the CGP , the contractor must achieve 70% revegetation on the site for it to be considered stable.

POST CONSTRUCTION BMP’SPost Construction

Vegetation – one of the best BMP’s!!!

Final Stabilization Criteria:

• 70% revegetation or

• Temporary erosion control measure in place, along with seed, to achieve 70% coverage

What’s your role as an inspector?

Preconstruction:

✓Make sure all BMP’s are installed properly

During Construction:

✓Make sure all the erosion and sediment control minimum requirements are covered

✓Make sure all BMP’s are maintained throughout the duration of the project

At Close of Construction:

✓ Is all the bare ground stabilized?

✓Are all temporary BMP’s removed (including DI protection)?

✓ Is all trash picked up?

What To Inspect

• All exposed surfaces. Look for visible signs of erosion

• The perimeter of the site. Look for signs of discharges

• All discharge points. Check that unauthorized discharges are not occurring

• All BMPs. Ensure they are functioning properly and identify maintenance issues

• All storage areas. Check for proper cover and containment

• Identify any potential sources of pollution

• If a discharge is occurring or has occurred, document if it and note whether it appears to have met water quality standards

Other Recommended Practices

• Maintain clear inspection reports

• Have a backup inspector

• Take photographs

SITE PREPARATION INSPECTION CHECKLIST

Rocked construction entrance

SWPPP sign posted

Perimeter controls

o Wattles

o Silt Fence

o Other

DI protection

Trash containment

Concrete washout

Temporary soil stabilization

method____________________

Dust control handled

Dewatering BMP’s

Other BMP’s installed ___________

SITE FINAL CHECKLIST

All bare ground stabilized? Including adjacent areas

disturbed during construction

70% revegetation or stabilization achieved?

All temporary BMP’s removed?

DI BAGS REMOVED?

Trash bin removed?

Trash around site picked up?

❖History of the EPA Clean Water Act❖City of Idaho Falls - Responsibility❖EPA Construction General Permit (CGP)❖BMP’s❖Checklists

THANK YOU!!!!

Engineering with a Mission, LLCSyman Company

Documents

City of Idaho Falls Erosion & Sediment Control