1

Remediation of Remediation of Impacts to WetlandsImpacts to Wetlands

Mitigation StrategiesMitigation Strategies

uuAvoidanceAvoidance

uuMinimizationMinimization

uuCompensationCompensation

Minimization of Wetland ImpactsMinimization of Wetland Impacts

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Steps in Compensatory MitigationSteps in Compensatory Mitigation

uu Define ObjectiveDefine Objective–– Regulatory AgenciesRegulatory Agencies–– Evaluation of ImpactsEvaluation of Impacts–– Regional NeedRegional Need–– Amenity of DevelopmentAmenity of Development–– Functional Need of DevelopmentFunctional Need of Development–– Choice of ApplicantChoice of Applicant

uu Describe General Characteristics of MitigationDescribe General Characteristics of Mitigation–– TypeType–– HydrologyHydrology–– VegetationVegetation

uu Site SelectionSite Selection–– FeasibilityFeasibility–– CostsCosts–– Constraints/OpportunitiesConstraints/Opportunities

Wetland Mitigation Site SelectionWetland Mitigation Site Selection

uuCriteriaCriteria–– FeasibilityFeasibility–– CostsCosts–– Constraints/OpportunitiesConstraints/Opportunities

uuSite Selection ProcessSite Selection Process–– OffOff--SiteSite–– OnOn--SiteSite–– Modify Plans to Suit SiteModify Plans to Suit Site

Site Selection InformationSite Selection Information

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Flow Chart of Compensatory MitigationFlow Chart of Compensatory Mitigation

Forms of Compensatory MitigationForms of Compensatory Mitigation

uuRestorationRestorationuuEnhancementEnhancementuuCreationCreationuuBankingBankinguuPayment InPayment In--lieu of lieu of

RestorationRestoration

uuRestoring wetland function to an Restoring wetland function to an area that was previously a wetland area that was previously a wetland and has been altered by change:and has been altered by change:–– HydrologyHydrology–– Vegetation Vegetation –– FillingFilling

4

Restoring Altered HydrologyRestoring Altered Hydrology

Restoring Altered Hydrology Restoring Altered Hydrology

Restoring Altered ElevationRestoring Altered Elevation

Before Excavation

After Excavation

Completed

5

Enhancement of FunctionsEnhancement of Functions

uuEnhancing a marginally functional Enhancing a marginally functional wetland to perform specific functionswetland to perform specific functions

Enhancing Habitat FunctionsEnhancing Habitat Functions

Before Enhancement After Enhancement

Enhancing Bank StabilizationEnhancing Bank Stabilization

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CreationCreation

uuCreating a wetland area where none Creating a wetland area where none existing beforeexisting before

Eagle Run Mitigation Eagle Run Mitigation -- Original Original ConditionsConditions

Eagle Run Mitigation Eagle Run Mitigation -- Grading Grading PlansPlans

7

Eagle Run Mitigation Eagle Run Mitigation -- ExcavationExcavation

Eagle Run Mitigation Eagle Run Mitigation -- Tidal SwaleTidal Swale

Eagle Run Mitigation Eagle Run Mitigation -- Gabion WeirGabion Weir

8

Eagle Run Mitigation Eagle Run Mitigation -- Low TideLow Tide

Tidal ConditionsTidal Conditions

High Tide

Low Tide

Costco Costco -- Grading PlanGrading Plan

9

Costco Costco -- Planting PlanPlanting Plan

Construction of Compensatory Construction of Compensatory MitigationMitigation

uu Timing Timing –– Early springEarly spring–– Late FallLate Fall

uu ActivitiesActivities–– Land PreparationLand Preparation

uu Clearing/GrubbingClearing/Grubbinguu ExcavationExcavationuu GradingGradinguu CompactingCompactinguu LinerLineruu Top SoilTop Soiluu Final GradingFinal Grading

–– PlantingPlantinguu Ground CoverGround Coveruu Specified PlantsSpecified Plants

Operation and MaintenanceOperation and Maintenance

uu IrrigationIrrigation–– First SeasonFirst SeasonuuSpring Spring –– inundate 1inundate 1 --2 inches for 52 inches for 5--7 days7 daysuuMidMid--Summer Summer –– inundate 5 inches for 3inundate 5 inches for 3--5 5

days, then increase to 10 inches 3days, then increase to 10 inches 3--5 days5 days

–– Second SeasonSecond SeasonuuSpring Spring –– inundate transition area at first inundate transition area at first

warm spell, lower when warm weather is set warm spell, lower when warm weather is set in for 5in for 5--10 days10 days

uuInundate 1 inches for 5Inundate 1 inches for 5--10 days10 days

10

Operation and Maintenance (cont.)Operation and Maintenance (cont.)

uuControl of Nuisance PlantsControl of Nuisance Plants–– HerbicideHerbicide–– MowingMowing

uuLongLong--TermTerm–– Periodic DrawPeriodic Draw--downdown–– Controlled burningControlled burning–– FencingFencing

Wetland Mitigation BankingWetland Mitigation Bankinguu ConceptConcept

–– Wetland Acreage Savings Account of Created WetlandsWetland Acreage Savings Account of Created Wetlands–– Withdrawal for Mitigation CreditWithdrawal for Mitigation Credit

uu AdvantagesAdvantages–– Implementing and functional before impactImplementing and functional before impact–– Large areas better than several small areasLarge areas better than several small areas–– Usually designed by experts with incentive to performUsually designed by experts with incentive to perform–– Bring together financial resources of manyBring together financial resources of many–– Reduce uncertainty of regulatory agenciesReduce uncertainty of regulatory agencies–– Easier for Regulatory Agencies to trackEasier for Regulatory Agencies to track

uu DisadvantagesDisadvantages–– If it fails there is a large lossIf it fails there is a large loss–– Sponsors take large risk with no guaranteeSponsors take large risk with no guarantee

uu IssuesIssues–– InIn--kindkind–– In WatershedIn Watershed–– Agency AgreementsAgency Agreements

Oregon Wetland BankingOregon Wetland Bankinguu Oregon Wetland Mitigation Bank Act Oregon Wetland Mitigation Bank Act –– 19871987uu Bank only used when onBank only used when on--site is not practicable or site is not practicable or

where offwhere off--site is environmentally preferablesite is environmentally preferableuu Requirements to Establish a Bank:Requirements to Establish a Bank:

–– Meet with DSLMeet with DSL–– Submit ProspectusSubmit Prospectus–– Develop InstrumentDevelop Instrument–– Location Location –– Need Need –– Existing Condition of Site/Adjacent AreasExisting Condition of Site/Adjacent Areas–– List of Adjacent Property OwnersList of Adjacent Property Owners–– Ecological GoalsEcological Goals–– Wetland FunctionsWetland Functions–– Site Plan (including buffers)Site Plan (including buffers)–– Monitoring PlanMonitoring Plan–– Contingency Plan (flood/invasive vegetation/eatContingency Plan (flood/invasive vegetation/eat--

out/etc.)out/etc.)–– Local ApprovalLocal Approval–– Plans for LongPlans for Long--term Managementterm Management

11

Oregon Wetland Banking (cont.)Oregon Wetland Banking (cont.)

uu DSL ReviewDSL Reviewuu Mitigation Bank Review Team Mitigation Bank Review Team

(ACOE/DSL/Others)(ACOE/DSL/Others)–– Review ProspectusReview Prospectus–– Participate in Development of InstrumentParticipate in Development of Instrument–– Review Performance (at least annually)Review Performance (at least annually)

uu DSL Approval DSL Approval uu Credits Depend on Method of Credits Depend on Method of

Mitigation DevelopmentMitigation Developmentuu Remaining Credits Can IncreaseRemaining Credits Can Increaseuu Buffers Can Earn Credits after 5 YearsBuffers Can Earn Credits after 5 Years

Wetland Mitigation by PaymentWetland Mitigation by Payment--InIn--LieuLieu

uu This mitigation option allows payment tied This mitigation option allows payment tied to the cost to replace the functions of the to the cost to replace the functions of the affected wetland, generally based on affected wetland, generally based on construction costsconstruction costs

uu The payment is made to the Division of The payment is made to the Division of State Lands for their discretionary use in State Lands for their discretionary use in wetland projectswetland projects

uu This option is only allowed for small impacts This option is only allowed for small impacts (0.2 acres), or by special authorization of (0.2 acres), or by special authorization of the Director of the Division of State Landsthe Director of the Division of State Lands

uu Payment determined as monetary value of Payment determined as monetary value of the lost/affected wetlands, usually by a the lost/affected wetlands, usually by a formula based on construction costs, and formula based on construction costs, and reserving the money in the contractreserving the money in the contract

Ranked Preference for Mitigation Ranked Preference for Mitigation OptionsOptions

uuOnOn--site, insite, in--kind kind uuOnOn--site, outsite, out--ofof--kind kind uuOffOff--site, insite, in--kind (inkind (in--basin) basin) uuOffOff--site, outsite, out--ofof--kind (Inkind (In--basin) basin) uu InIn--Basin Mitigation Bank Basin Mitigation Bank uu InIn--Basin PaymentBasin Payment--toto--Provide Provide uuPaymentPayment--inin--Lieu Lieu

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MonitoringMonitoring

uu Purpose of EvaluationPurpose of Evaluation–– RegulatoryRegulatory–– CorrectionCorrection

uu Functions to EvaluateFunctions to Evaluate–– GroundwaterGroundwater–– Flood StorageFlood Storage–– Shoreline StabilizationShoreline Stabilization–– Sediment TrappingSediment Trapping–– Water QualityWater Quality–– Food Chain SupportFood Chain Support–– Wildlife HabitatWildlife Habitat–– Aquatic HabitatAquatic Habitat–– Recreation Recreation

Government Island MonitoringGovernment Island Monitoring

Effectiveness of Wetland MitigationEffectiveness of Wetland Mitigation

uuNational Research Council 2001National Research Council 2001–– Net Loss in Wetland AreaNet Loss in Wetland Area–– Net Loss in Wetland FunctionNet Loss in Wetland Function

uuMitigation SuccessMitigation Success–– Highly successfulHighly successful–– Highly unsuccessfulHighly unsuccessful

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Factors Contributing to Lack of Factors Contributing to Lack of SuccessSuccess

Lack of experience Lack of experience 1010

Lack of consistency between goals and planLack of consistency between goals and plan99

A buffer too small or A buffer too small or unvegetatedunvegetated88

Compacted soilsCompacted soils77

Lack of followLack of follow--up by Regulatory Agenciesup by Regulatory Agencies66

Lack of hydrologic monitoring prior to Lack of hydrologic monitoring prior to constructionconstruction

55

Poor mitigation designPoor mitigation design44

Lack of maintenanceLack of maintenance33

Poor site selectionPoor site selection22

No irrigation of planted materialsNo irrigation of planted materials11

Johnson et al. 2002

Factors Contributing to SuccessFactors Contributing to Success

Hydrologic monitoring prior to constructionHydrologic monitoring prior to construction1010

Irrigation for at least 1 growing seasonIrrigation for at least 1 growing season99

Maintenance conducted on siteMaintenance conducted on site88

Native seed source presentNative seed source present77

Good mitigation designGood mitigation design66

Designer onDesigner on--site during constructionsite during construction55

Oversight and followOversight and follow--up by Regulatory Agenciesup by Regulatory Agencies44

Good site selectionGood site selection33

Same consultantSame consultant22

Adequate source of hydrologyAdequate source of hydrology11

Johnson et al. 2002

National Compensatory Mitigation Action PlanNational Compensatory Mitigation Action Plan

uu 17 Actions to be completed by 200517 Actions to be completed by 2005uu GeneralGeneral

–– Regulatory GuidanceRegulatory Guidanceuu Integrating Mitigation into WatershedIntegrating Mitigation into Watershed

–– On Site/Off Site & InOn Site/Off Site & In--kind/Out of Kind guidancekind/Out of Kind guidance–– Vegetated Buffer GuidanceVegetated Buffer Guidance–– Preservation GuidancePreservation Guidance–– Watershed Context GuidanceWatershed Context Guidance

uu Improving AccountabilityImproving Accountability–– Banking GuidanceBanking Guidance–– Grants to Improve MitigationGrants to Improve Mitigation–– Guidance for “Difficult To Replace” AreasGuidance for “Difficult To Replace” Areas–– Stream MitigationStream Mitigation

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National CompensatoryNational CompensatoryMitigation Action Plan (cont.)Mitigation Action Plan (cont.)

uu Clarifying Performance StandardsClarifying Performance Standards–– Model Mitigation ChecklistModel Mitigation Checklist–– Adapt NASAdapt NAS--guidelines to 404 Programguidelines to 404 Program–– Analysis of Existing StandardsAnalysis of Existing Standards–– Clarify Performance Standard ConceptsClarify Performance Standard Concepts–– Performance Standard GuidancePerformance Standard Guidance

uu Improving Data CollectionImproving Data Collection–– Evaluate Existing Mitigation DatabasesEvaluate Existing Mitigation Databases–– Develop Common Mitigation DatabasesDevelop Common Mitigation Databases–– Annual Report CardAnnual Report Card