Presentation on theme: "Buffers and Special Water Quality Protections"— Presentation transcript:
1Buffers and Special Water Quality Protections Carrie J. Evenson, Ph.D.Environmental Programs Specialist IVIndustrial Wastewater Enforcement SectionWater Quality DivisionDepartment of Environmental QualityJason R. Vogel, Ph.D., P.E.Assistant ProfessorExtension Stormwater SpecialistBiosystems and Agricultural Engr.Oklahoma State University
2Outline Special Water Quality Protections Buffer Requirements Outstanding Resource Waters (ORWs)Aquatic Resources of Concern (ARCs)Endangered/Threatened SpeciesImpaired WatersBuffer Requirements
4Outstanding 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 AInclude Illinois River & Lee Creek watersheds and Mountain Fork River watershedAddendum F of OKR10 indicates locations
6Outstanding Resource Water/Aquatic Resource of Concern Aquatic Resources of Concern (ARCs)Includes sections of the following:Grand (Neosho) RiverGlover RiverCimarron RiverMountain Fork RiverSouth Canadian RiverSpring RiverMuddy Boggy RiverIllinois RiverKiamichi RiverLee and Little Lee CreeksLittle RiverCertain watersheds
7Outstanding Resource Water/Aquatic Resource of Concern Aquatic Resources of Concern (ARCs)Counties with no stormwater discharge-sensitive endangered/threatened species:AlfalfaGarvinMurrayStevensBeckhamGrantNowataTexasCarterGreerOkfuskeeWashitaCimarronJohnstonOklahomaWashingtonComancheKiowaOkmulgeeGarfieldLincolnRogers
9Outstanding Resource Water/Aquatic Resource of Concern For sites discharging to ORW/ARCIndicate on NOI and address in SWP3Inspection requirementsMinimum 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
10Outstanding Resource Water/Aquatic Resource of Concern For sites discharging to ORW/ARCStabilization requirementsInitiated immediately following day earth-disturbing activities have temporarily or permanently ceasedCompleted within 7 daysCorrective actions required
11Outstanding Resource Water/Aquatic Resource of Concern For sites discharging to ORW/ARC100 ft buffer zone requiredAlternately, use Addendum I “Buffer Guidance” for equivalent controlsTemporary or permanent sediment basin required for areas that serve an area with ≥5 acres disturbed
12Outstanding Resource Water/Aquatic Resource of Concern For sites discharging to ARCDischarge must be protective of listed endangered/threatened species or designated critical habitatApplicant must comply with requirements, conditions, terms identified as necessary to meet eligibility requirements
13Endangered/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
14Endangered/Threatened Species Procedure for assessing potential effects of discharge on listed species (see Part 11):Complete prior to submitting NOIStep 1: Determine if project discharges to ARCIf project doesn’t discharge to ARC, no additional steps are necessary.If project does discharge to ARC, proceed to Step 2.
15Endangered/Threatened Species Procedure for assessing potential effects of discharge on listed species (see Part 11):Step 2: Implement stormwater control measures to protect listed speciesRetain sediment on site to the greatest extent practicableEstablish/retain 100 ft buffer zone or equivalentFollow stabilization requirements
16Endangered/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; ORSite is located within ARC corridor and SWP3 describes area and measures used to protect species or habitat; OR
17Endangered/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 consultationMust include documentation demonstrating Section 7 consultation; ORApplicant’s discharge(s) is/are addressed in another operator’s certification of eligibility
18Endangered/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 guidanceNo longer necessary to contact USFWS for guidance on alternatives
19Impaired WatersIdentified by State or EPA pursuant to Section 303(d) of the Clean Water Act as not meeting applicable State water quality standardsIncludesWaters with approved or established TMDLs, andWaters for which a TMDL has not yet been established or approved
20Impaired Waters303(d) list and approved TMDLs/watershed plans can be found on DEQ website:For 303(d) list:For approved TMDLs/watershed plans:
21Impaired WatersFor sites discharging pollutants of concern to receiving water on 303(d) list:Document how BMPs will control discharge of pollutants of concernIf TMDL or watershed plan has been approvedDescribe how SWP3 is consistent with TMDL/watershed plan
22Impaired WatersFor sites within one mile of streams impaired for sediment:Indicate on Notice of IntentInspection requirementsMinimum 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
23Impaired WatersFor sites within one mile of streams impaired for sediment:Corrective actionsDocument within 24 hours and implement within 7 days of discoveryStabilization requirementsInitiated immediately following day earth-disturbing activities have temporarily or permanently ceasedCompleted within 7 days
25Buffer 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 ORWProvide 50 feet of natural buffer as measured from the top of the bank to disturbed portions of the site
26Buffer Requirements Two (2) buffer requirements (see Addendum I) Alternative 2:For sites discharging to the watershed of ARC and/or ORWProvide 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.
27Buffer RequirementsRetain and protect as much natural buffer from construction activities as possiblePreexisting structures and impervious surfaces are allowed in buffer provided vegetation outside preexisting disturbance is maintained
28Buffer RequirementsDo not conduct earth-disturbing activities within buffer during permit coverageEnsure all discharges are first treated by erosion and sediment controls before entering buffer
29Buffer RequirementsNatural 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 existNo natural buffer exists due to preexisting development disturbances (e.g., structures, impervious surfaces)
30Buffer Requirements Three compliance alternatives Alternative 1: Provide and maintain a 50/100-foot undisturbed natural bufferAlternative 2: Provide and maintain <50/100-foot buffer and install additional erosion and sediment controlsAlternative 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
31Buffer Requirements Using Addendum I Step 1: Determine if buffer is requiredStep 2: Determine which compliance alternative to useStep 3: If Alternative 1, measure existing buffer width and retain and protect required natural buffer widthMeasured perpendicularly from the ordinary high water mark or the edge of the stream or river bank, bluff or cliffFor meandering waterbodies, you may measure in regular intervals instead of measuring each change
34Buffer 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 SWP3Determine what additional controls must be implemented along with any retained natural bufferAddendum I lists process for determining which BMP or combination of BMPs can provide equivalent sediment reduction as natural buffer
36Buffer Requirements Determining equivalent sediment reduction Step 1: Estimate removal efficiency at site if 50/100 ft buffer could be providedEquivalent erosion and sediment controls must provide sediment load reduction equivalent to thisDependent on site-specific factorsIncludes 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
37Buffer Requirements Estimating removal efficiency of buffer Use buffer performance standards included in Appendix I, Tables I-1 through I-4ORConduct a site-specific calculation for sediment removal efficiencyProvide the specific removal efficiency and the information used for the site-specific calculation in your SWP3
38Buffer 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 UniversityChoose vegetation type that most closely matches vegetation that would exist naturally, regardless of conditionNo supplemental planting requiredTake credit as a fully vegetated “natural buffer” in subsequent calculations
39Buffer Requirements Example: I am developing a commercial site in Oklahoma City.How do I know if I need to have a buffer?Take a look at how close the site is to the nearest surface water
41Buffer RequirementsI’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 requiredIs surface water an ORW or ARC?If NO – 50 ft buffer requiredIf YES – 100 ft buffer required
42Buffer RequirementsSo I know I need to provide a 50 ft buffer. What’s next?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 projectIf NO – determine how much of a buffer can be provided and what equivalent sediment control measures you will install insteadUse Tables I-1 through I-4 for this
43Buffer RequirementsI 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 bufferSite location: Oklahoma CityNatural buffer vegetation: WeedsSite condition: Blade fillSoil type: Sand
45Buffer Requirements Example using Appendix I, Tables I-1 through I-4: Site location: Oklahoma CityNatural buffer vegetation: WeedsSite condition: Blade fillSoil type: SandSediment removal efficiency based on Table I-1: 41%
46Buffer RequirementsI 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 andUse Table I-1 through I-4 to determine sediment load reduction ORUse a model or other type of calculator showing how BMPs meet or exceed the sediment removal efficiency from Step 1
47Buffer Requirements If using Appendix I, Tables I-1 through I-4: Site location: Oklahoma CityNatural buffer vegetation: WeedsSite condition: Blade fillSoil type: SandSediment removal efficiency of buffer based on Table I-1: 41%Proposed sediment control measure: 12” waddle
49Buffer Requirements Using Appendix I, Tables I-1 through I-4: Site location: Oklahoma CityNatural buffer vegetation: WeedsSite condition: Blade fillSoil type: SandSediment removal efficiency of buffer based on Table I-1: 41%Proposed sediment control measure: 12” waddleEquivalent sediment reduction of control measure: 90%
50Buffer RequirementsMy 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 usedORSpecific removal efficiency and other information for site-specific calculationStormwater control(s), model or calculator used (other than Tables), and results of calculations
51Buffer RequirementsSo what if I don’t want to use Tables I-1 through I-4?Use other available calculation methods or models
53Alternative Calculation Methods Model options for calculating effectiveness of alternative controlsRUSLE-series programs (USDA)WEPP (USDA)SEDIMOT series (downloadable, developed by Barfield et al.)SedPro (Woolpert, Inc.)SEDCAD (Civil Software Design, LLC)
54RUSLE – Revised Universal Soil Loss Equation A = (R)(K)(LS)(C)(P)A=Erosion per unit areaK=Soil ErodibilityLS=Land slope and lengthC=degree of soil coverSupporting practices
55Erosivity - R Measure of erosivity of climate at a location Las Vegas, NV 8Phoenix, AZ 22Denver, CO 40Syracuse, NY 80Minneapolis, MN 110Chicago, IL 140Richmond, VA 200St. Louis, MO 210Tulsa, OK 260Dallas, TX 275Birmingham, AL 350Charleston, SC 400New Orleans, LA 700Erosivity varies greatly by location. Climate is about 100 times more erosive in New Orleans than in Las Vegas.
56SOIL ERODIBILITY - K Effect of texture clay ( ) resistant to detachmentsand ( ) easily detached, low runoff, large, dense particles not easily transportedsilt loam ( ) moderately detachable, moderate to high runoffsilt ( ) easily detached, high runoff, small, easily transported sedimentValues shown in parenthesis are typical K factors for those texture groups.
57LS Factor – Length Slope Describes TopographyOverland flow slope lengthSlope lengths for eroding portions of hillslopesSteepnessHillslope shapeThese are the main variables that determine how topography affects erosion.
58Slope Length for Eroding Portion of Slope Only works for simple slopesTraditional definitionDistance from origin of overland flow to concentrated flow or to where deposition beginsDefinition is flawed for strips and concave:convex slopesBest approach: Use overland flow slope length and examine RUSLE2 slope segment soil loss valuesThis approach is the traditional way of applying erosion prediction for conservation planning.It is still a good method for simple situations.Sometimes determining where deposition begins is a problem on concave slopes.RUSLE2 determines that location. The location varies on a daily basis as conditions vary daily.
59Detachment Proportional to Slope Steepness Factor (S) Not affected by any other variableThis figure shows the slope steepness factor relationship used in RUSLE2. Detachment is proportional to the slope steepness factor. It is not a function of anything in contrast to the slope length factor.However,in actuality the slope steepness is a function of the ratio of rill to interrill erosion but the science isn’t sufficient to develop a working relationship.
60C & P Factors – Based on Land Use C: Cover-managementP: Supporting practicesTwo factor reflect the influence of land use in RUSLE2.These factors are for cover-management and supporting practices.Conservation practices are based on either cover-management and/or supporting practices.Referring to supporting practices as conservation practices is improper. No-till is a wonderful conservation practice that works entirely though cover-management effects.
61Cover-Management Vegetative community Crop Crop rotation Conservation tillageApplication of surface and buried materials (mulch, manure)Increasing random roughnessCover-management is used in a variety of ways for erosion control and conservation practices.b
62Supporting Practices Erosion control (called permeable barriers) Silt fence, waddles, check damsContouringStrip systemsBuffer, filter, strip cropping, barriersTerrace/DiversionImpoundmentsSupporting practices are primarily related to practices that affect transport capacity of runoff.
63Changing the Average Steepness and Length of Slope ExampleChanging the Average Steepness and Length of Slope