Buffers and Special Water
Quality Protections
Carrie J. Evenson, Ph.D.
Environmental Programs Specialist IV
Industrial Wastewater Enforcement Section
Water Quality Division
Department of Environmental Quality
Jason R. Vogel, Ph.D., P.E.
Assistant Professor
Extension Stormwater Specialist
Biosystems and Agricultural Engr.
Oklahoma State University
Outline
 Special Water Quality Protections
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Outstanding Resource Waters (ORWs)
Aquatic Resources of Concern (ARCs)
Endangered/Threatened Species
Impaired Waters
 Buffer Requirements
Special Water Quality
Protections
Outstanding Resource
Water/Aquatic Resource of Concern
 Outstanding Resource Waters (ORWs)
 Waters of the State designated in Oklahoma’s Water
Quality Standards, OAC 785:45, Appendix A
 Include Illinois River & Lee Creek watersheds and
Mountain Fork River watershed
 Addendum F of OKR10 indicates locations
Outstanding Resource
Water/Aquatic Resource of Concern
 Aquatic Resources of Concern (ARCs)
 Includes sections of the following:
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Grand (Neosho) River
Cimarron River
South Canadian River
Muddy Boggy River
Kiamichi River
Little River
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Glover River
Mountain Fork River
Spring River
Illinois River
Lee and Little Lee Creeks
Certain watersheds
Outstanding Resource
Water/Aquatic Resource of Concern
 Aquatic Resources of Concern (ARCs)
 Counties with no stormwater discharge-sensitive
endangered/threatened species:
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Alfalfa
Beckham
Carter
Cimarron
Comanche
Garfield
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Garvin
Grant
Greer
Johnston
Kiowa
Lincoln
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Murray
Nowata
Okfuskee
Oklahoma
Okmulgee
Rogers
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Stevens
Texas
Washita
Washington
Outstanding Resource
Water/Aquatic Resource of Concern
 For sites discharging to ORW/ARC
 Indicate on NOI and address in SWP3
 Inspection requirements
 Minimum of once every 7 days and within 24 hours of a storm
event of ≥0.5 inches or within 24 hours of snowmelt-related
discharge
Outstanding Resource
Water/Aquatic Resource of Concern
 For sites discharging to ORW/ARC
 Stabilization requirements
 Initiated immediately following day earth-disturbing activities
have temporarily or permanently ceased
 Completed within 7 days
 Corrective actions required
Outstanding Resource
Water/Aquatic Resource of Concern
 For sites discharging to ORW/ARC
 100 ft buffer zone required
 Alternately, use Addendum I “Buffer Guidance” for
equivalent controls
 Temporary or permanent sediment basin required for
areas that serve an area with ≥5 acres disturbed
Outstanding Resource
Water/Aquatic Resource of Concern
 For sites discharging to ARC
 Discharge must be protective of listed
endangered/threatened species or designated critical
habitat
 Applicant must comply with requirements, conditions,
terms identified as necessary to meet eligibility
requirements
Endangered/Threatened Species
Important Note:
Permit does not authorize discharges that cause a
prohibited “take” or that are likely to jeopardize
continued existence of species or habitat
Endangered/Threatened Species
 Procedure for assessing potential effects of discharge
on listed species (see Part 11):
 Complete prior to submitting NOI
 Step 1: Determine if project discharges to ARC
 If project doesn’t discharge to ARC, no additional steps are
necessary.
 If project does discharge to ARC, proceed to Step 2.
Endangered/Threatened Species
 Procedure for assessing potential effects of discharge
on listed species (see Part 11):
 Step 2: Implement stormwater control measures to
protect listed species
 Retain sediment on site to the greatest extent practicable
 Establish/retain 100 ft buffer zone or equivalent
 Follow stabilization requirements
Endangered/Threatened Species
 Applicant must certify that it meets at least ONE of
following criteria:
 Site is not located within any of the Aquatic Resource of
Concern (ARC) corridors; OR
 Site is located within ARC corridor and SWP3 describes
area and measures used to protect species or habitat;
OR
Endangered/Threatened Species
 Applicant must certify that it meets at least ONE of
following criteria (cont’d):
 Site is federally approved/authorized and addresses
Endangered Species act Section 7 consultation
 Must include documentation demonstrating Section 7
consultation; OR
 Applicant’s discharge(s) is/are addressed in another
operator’s certification of eligibility
Endangered/Threatened Species
 Applicant must certify that it meets at least ONE of
following criteria (cont’d):
 If one of above can’t be met, may use Buffer Guidance
to select equivalent sediment controls or contact DEQ
for guidance
 No longer necessary to contact USFWS for guidance on
alternatives
Impaired Waters
 Identified by State or EPA pursuant to Section 303(d)
of the Clean Water Act as not meeting applicable
State water quality standards
 Includes
 Waters with approved or established TMDLs, and
 Waters for which a TMDL has not yet been established or
approved
Impaired Waters
 303(d) list and approved TMDLs/watershed plans can
be found on DEQ website:
 For 303(d) list:
http://www.deq.state.ok.us/wqdnew/305b_303d/index.
html
 For approved TMDLs/watershed plans:
http://www.deq.state.ok.us/wqdnew/tmdl/index.html
Impaired Waters
 For sites discharging pollutants of concern to
receiving water on 303(d) list:
 Document how BMPs will control discharge of
pollutants of concern
 If TMDL or watershed plan has been approved
 Describe how SWP3 is consistent with TMDL/watershed
plan
Impaired Waters
 For sites within one mile of streams impaired for
sediment:
 Indicate on Notice of Intent
 Inspection requirements
 Minimum of once every 7 days and within 24 hours of a
storm event of ≥0.5 inches or within 24 hours of snowmeltrelated discharge
Impaired Waters
 For sites within one mile of streams impaired for
sediment:
 Corrective actions
 Document within 24 hours and implement within 7 days of
discovery
 Stabilization requirements
 Initiated immediately following day earth-disturbing
activities have temporarily or permanently ceased
 Completed within 7 days
Buffer Requirements
Buffer Requirements
 Two (2) buffer requirements (see Addendum I)
 Alternative 1:
 For sites discharging into receiving water located on
or immediately adjacent to your site that are not an
ARC or ORW
 Provide 50 feet of natural buffer as measured from the
top of the bank to disturbed portions of the site
Buffer Requirements
 Two (2) buffer requirements (see Addendum I)
 Alternative 2:
 For sites discharging to the watershed of ARC and/or
ORW
 Provide 100 feet of vegetated buffer between area
disturbed and all perennial or intermittent streams; or
50 feet of vegetated buffer between area disturbed and
all ephemeral streams or drainages.
Buffer Requirements
 Retain and protect as much natural buffer from
construction activities as possible
 Preexisting structures and impervious surfaces are
allowed in buffer provided vegetation outside preexisting
disturbance is maintained
Buffer Requirements
 Do not conduct earth-disturbing activities within
buffer during permit coverage
 Ensure all discharges are first treated by erosion and
sediment controls before entering buffer
Buffer Requirements
 Natural buffers and equivalent sediment controls
don’t apply when:
 Water crossings, limited water access, and stream
restoration authorized under a Clean Water Act (CWA)
Section 404 permit exist
 No natural buffer exists due to preexisting development
disturbances (e.g., structures, impervious surfaces)
Buffer Requirements
 Three compliance alternatives
 Alternative 1: Provide and maintain a 50/100-foot
undisturbed natural buffer
 Alternative 2: Provide and maintain <50/100-foot buffer
and install additional erosion and sediment controls
 Alternative 3: Implement equivalent erosion and
sediment controls to achieve the same sediment load
reduction as provided by a 50/100 foot natural buffer if
natural buffer of any size is infeasible
Buffer Requirements
 Using Addendum I
 Step 1: Determine if buffer is required
 Step 2: Determine which compliance alternative to use
 Step 3: If Alternative 1, measure existing buffer width
and retain and protect required natural buffer width
 Measured perpendicularly from the ordinary high water
mark or the edge of the stream or river bank, bluff or cliff
 For meandering waterbodies, you may measure in regular
intervals instead of measuring each change
Buffer Requirements
 Step 4: If Alternative 2 or 3 selected:
 Document width and location of buffer in SWP3 (Alt. 2)
 Document why it is infeasible to provide and maintain
an undisturbed natural buffer of any size in the SWP3
 Determine what additional controls must be
implemented along with any retained natural buffer
 Addendum I lists process for determining which BMP or
combination of BMPs can provide equivalent sediment
reduction as natural buffer
Buffer Requirements
 Determining equivalent sediment reduction
 Step 1: Estimate removal efficiency at site if 50/100 ft
buffer could be provided
 Equivalent erosion and sediment controls must provide
sediment load reduction equivalent to this
 Dependent on site-specific factors
 Includes precipitation, soil type, land cover, slope length,
width, steepness, and types of sediment controls used to
reduce the discharge of sediment prior to the buffer
Buffer Requirements
 Estimating removal efficiency of buffer
 Use buffer performance standards included in Appendix
I, Tables I-1 through I-4
OR
 Conduct a site-specific calculation for sediment removal
efficiency
 Provide the specific removal efficiency and the information
used for the site-specific calculation in your SWP3
Buffer Requirements
 Things to note when using Tables I-1 through I-4:
 Developed by Dr. Jason Vogel and Katie Beitz, Biosystems
and Agricultural Engineering, Oklahoma State University
 Choose vegetation type that most closely matches
vegetation that would exist naturally, regardless of condition
 No supplemental planting required
 Take credit as a fully vegetated “natural buffer” in subsequent
calculations
Buffer Requirements
 Example:
 I am developing a commercial site in Oklahoma City.
 How do I know if I need to have a buffer?
1.
Take a look at how close the site is to the nearest surface
water
Buffer Requirements
 I’ve looked at my site, and it looks like I will need to
clear ground within 50 feet of the stream in order to
build my parking lot. Now what?
 Earth-disturbing activities will occur within 50 feet of
surface water: Buffer is required
 Is surface water an ORW or ARC?
 If NO – 50 ft buffer required
 If YES – 100 ft buffer required
Buffer Requirements
 So I know I need to provide a 50 ft buffer. What’s next?
1.
Determine if you can provide the entire 50 feet of
undisturbed buffer on your site.
 If YES – protect buffer from earth-disturbing activities for the
duration of the project
 If NO – determine how much of a buffer can be provided and
what equivalent sediment control measures you will install
instead
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Use Tables I-1 through I-4 for this
Buffer Requirements
 I can’t maintain any buffer at my site. Now what do I do?
 Use Appendix I, Tables I-1 through I-4 to determine
sediment reduction provided by 50 feet of undisturbed
natural buffer
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Site location: Oklahoma City
Natural buffer vegetation: Weeds
Site condition: Blade fill
Soil type: Sand
Buffer Requirements
 Example using Appendix I, Tables I-1 through I-4:
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Site location: Oklahoma City
Natural buffer vegetation: Weeds
Site condition: Blade fill
Soil type: Sand
Sediment removal efficiency based on Table I-1: 41%
Buffer Requirements
 I found the removal efficiency of a natural buffer at my
site. How do I determine what sediment controls can
provide an equivalent sediment load reduction?
 Select stormwater control(s) you want to use and
 Use Table I-1 through I-4 to determine sediment load reduction
OR
 Use a model or other type of calculator showing how BMPs
meet or exceed the sediment removal efficiency from Step 1
Buffer Requirements
 If using Appendix I, Tables I-1 through I-4:
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Site location: Oklahoma City
Natural buffer vegetation: Weeds
Site condition: Blade fill
Soil type: Sand
Sediment removal efficiency of buffer based on Table I-1:
41%
 Proposed sediment control measure: 12” waddle
Buffer Requirements
 Using Appendix I, Tables I-1 through I-4:
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Site location: Oklahoma City
Natural buffer vegetation: Weeds
Site condition: Blade fill
Soil type: Sand
Sediment removal efficiency of buffer based on Table I-1: 41%
Proposed sediment control measure: 12” waddle
Equivalent sediment reduction of control measure: 90%
Buffer Requirements
 My selected sediment control provides adequate sediment
load efficiency. Am I done yet?
 Document information from previous steps in SWP3 including:
 Buffer vegetation and soil type if Tables I-1 through I-4 are used
OR
 Specific removal efficiency and other information for site-specific
calculation
 Stormwater control(s), model or calculator used (other than
Tables), and results of calculations
Buffer Requirements
 So what if I don’t want to use Tables I-1 through I-4?
 Use other available calculation methods or models
Alternative Calculation Methods
Alternative Calculation Methods
 Model options for calculating effectiveness of alternative
controls
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RUSLE-series programs (USDA)
WEPP (USDA)
SEDIMOT series (downloadable, developed by Barfield et al.)
SedPro (Woolpert, Inc.)
SEDCAD (Civil Software Design, LLC)
RUSLE – Revised Universal Soil
Loss Equation
A = (R)(K)(LS)(C)(P)
A=Erosion per unit area
K=Soil Erodibility
LS=Land slope and length
C=degree of soil cover
Supporting practices
Erosivity - R
Measure of erosivity of climate at a location
Las Vegas, NV
Phoenix, AZ
Denver, CO
Syracuse, NY
Minneapolis, MN
Chicago, IL
8
22
40
80
110
140
Richmond, VA
St. Louis, MO
Tulsa, OK
Dallas, TX
Birmingham, AL
Charleston, SC
New Orleans, LA
200
210
260
275
350
400
700
SOIL ERODIBILITY - K
 Effect of texture
 clay (0.1 - 0.2) resistant to detachment
 sand (0.05 - 0.15) easily detached, low runoff, large,
dense particles not easily transported
 silt loam (0.25 - 0.35) moderately detachable,
moderate to high runoff
 silt (0.4 -0.6) easily detached, high runoff, small,
easily transported sediment
LS Factor – Length Slope
 Describes Topography
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Overland flow slope length
Slope lengths for eroding portions of hillslopes
Steepness
Hillslope shape
Slope Length for Eroding Portion
of Slope
 Only works for simple slopes
 Traditional definition
 Distance from origin of overland flow to concentrated
flow or to where deposition begins
 Definition is flawed for strips and concave:convex slopes
 Best approach: Use overland flow slope length and
examine RUSLE2 slope segment soil loss values
Detachment Proportional to Slope
Steepness Factor (S)
Not affected by any other variable
4.5
4
Factor Value
3.5
3
2.5
2
1.5
1
0.5
0
0
5
10
15
20
Slope Steepness (%)
25
30
35
C & P Factors – Based on Land
Use
 C: Cover-management
 P: Supporting practices
Cover-Management
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Vegetative community
Crop
Crop rotation
Conservation tillage
Application of surface and buried materials (mulch,
manure)
 Increasing random roughness
Supporting Practices
 Erosion control (called permeable barriers)
 Silt fence, waddles, check dams
 Contouring
 Strip systems
 Buffer, filter, strip cropping, barriers
 Terrace/Diversion
 Impoundments
Example
Changing the
Average Steepness
and Length of
Slope
Choosing the
Location
Example: Tulsa, OK
Choosing the Soil
of the Site
Example: Silt Loam
Choosing the
Management of
the Surface
Example: the first
50 feet are blade
cut
Choosing the
Management of
the Surface
Example: we
added a silt fence
at 50 feet, and
added a barrier
strip for the
second 50’ of the
area
Adding a Wattle
Example: 6”
Wattle
In this screen you
can also set the
spacing, and
number of wattles
used
Estimate Sediment
Removal
Soil Loss - Sediment
Delivery
Soil Loss
Example:
39-2.5/39 = 94%
Questions, Comments, Discussion