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STREAMBANK EROSION STREAMBANK EROSION CONTROL ALTERNATIVESCONTROL ALTERNATIVES

Frank Reckendorf, PhDFrank Reckendorf, PhD(Reckendorf and Associates Salem,OR (Reckendorf and Associates Salem,OR frecken@mac.comfrecken@mac.com))

(volunteering for SERNW) (volunteering for SERNW) Barry Southerland, PhBarry Southerland, PhDD

(USDA, Natural Resources Conservation Service, West (USDA, Natural Resources Conservation Service, West National Technical Support Center, Portland, OR National Technical Support Center, Portland, OR

Barry.Southerland@Barry.Southerland@porpor..usdausda..govgov))

forforPNWSWS & SERNW, Vancouver, WAPNWSWS & SERNW, Vancouver, WA

May 4, 2005May 4, 2005

STREAMBANK EROSION CONTROL STREAMBANK EROSION CONTROL ALTERNATIVESALTERNATIVES

Planning, Evaluation, and Design Overview Workshop Planning, Evaluation, and Design Overview Workshop –– May 4th, 2006May 4th, 2006 NW Chapter Society of Ecological Restoration NW Chapter Society of Ecological Restoration –– Vancouver, WAVancouver, WA

Understanding the Resource Problem

Understanding Process

Understanding the reference and desired future condition

Using system(s) (fluvial and watershed approaches) to solve streambank erosion problems

IntroductionIntroductionWorkshop HousekeepingWorkshop HousekeepingParticipant IntroductionsParticipant IntroductionsBinder, Design to Dirt CD, Soil Binder, Design to Dirt CD, Soil Bioengineering, Hoag and Bioengineering, Hoag and FrippFripp, 2002 , 2002 Design to Dirt Contents Review (see Design to Dirt Contents Review (see Binder)Binder)Minimum Time Spent in Workshop on Minimum Time Spent in Workshop on Some Slides Because of Time Frame, but Some Slides Because of Time Frame, but “All Slides” will be in the Follow“All Slides” will be in the Follow--up CDup CD

What Is Streambank Erosion?What Is Streambank Erosion?

Streambank erosion is that part of Streambank erosion is that part of channel erosion in which material is channel erosion in which material is eroded from the streambank and eroded from the streambank and deposited at the base of the slope or deposited at the base of the slope or in the channel. Streambank erosion in the channel. Streambank erosion is usually associated with erosion of is usually associated with erosion of the streambed. It occurs along the streambed. It occurs along perennial, intermittent, and perennial, intermittent, and ephemeral streams. ephemeral streams.

Planning and EvaluationPlanning and Evaluation

Any evaluation of streambank Any evaluation of streambank erosion should be done in a erosion should be done in a planning and evaluation context planning and evaluation context that is cyclic. In other words there that is cyclic. In other words there is a cycle and feedback from is a cycle and feedback from objectives to resource evaluation objectives to resource evaluation to cause and effect to solutions to to cause and effect to solutions to objectives. objectives.

Planning StepsPlanning Steps

Determining ObjectivesDetermining ObjectivesAssessment Including Appropriate Assessment Including Appropriate Environmental AssessmentEnvironmental Assessment–– PhysicalPhysical–– BiologicalBiological–– ChemicalChemical–– ArcheologicalArcheological–– SocialSocial

Planning Cont. Planning Cont.

Interpreting, and AnalyzingInterpreting, and AnalyzingDeveloping AlternativesDeveloping AlternativesDocumenting DecisionsDocumenting DecisionsEstablish Funding and Establish Funding and EnvEnv. Clearance. ClearanceImplementationImplementationMonitoringMonitoring

Restoration PlanningRestoration Planning (see SER PRIMER sec. 3)(see SER PRIMER sec. 3)

A clear rational as to why restoration is A clear rational as to why restoration is neededneededA statement of the goals and objectives of A statement of the goals and objectives of the restoration projectthe restoration projectAn ecological description of the site An ecological description of the site designated for restorationdesignated for restorationAn ecological description of the reference An ecological description of the reference (see page 8 of PRIMMER multiple sites)(see page 8 of PRIMMER multiple sites)

East Side Stream in Valley Type “V”, East Side Stream in Valley Type “V”, (Glacial(Glacial--FluvFluv. Trough) Refer. Reach. Trough) Refer. Reach

White River, WA

East Slope Cascades

Restoration Planning Cont.Restoration Planning Cont.

An explanation of how the proposed An explanation of how the proposed restoration will integrate with the restoration will integrate with the landscape and flows of organisms landscape and flows of organisms and materialsand materials

Restoration Planning. Cont.Restoration Planning. Cont.Explicit plans, schedules, and budgets for Explicit plans, schedules, and budgets for site preparation, installation and post site preparation, installation and post installation activities, including a strategy installation activities, including a strategy for making prompt midfor making prompt mid--course course corrections.corrections.Well developed and explicitly stated Well developed and explicitly stated performance standards, with monitoring performance standards, with monitoring protocols by which the projects can be protocols by which the projects can be evaluated.evaluated.Strategies for longStrategies for long--term protection and term protection and maintenance of the restored ecosystem. maintenance of the restored ecosystem.

Comparison Std. Plan. Rest. Comparison Std. Plan. Rest. PLANNINGPLANNINGDET. OBJECTIVESDET. OBJECTIVESASSESSMENT ASSESSMENT –– Physical,BiologicalPhysical,Biological–– Chem.,Arch.,SocialChem.,Arch.,Social

Interpreting, and Interpreting, and AnalyzingAnalyzing

RESTORATION PLANNINGRESTORATION PLANNING

A clear rational as to why A clear rational as to why restoration is needed.restoration is needed.

A statement of the goals A statement of the goals and objectives of the and objectives of the restoration project.restoration project.

An ecological description An ecological description of the site designated for of the site designated for restoration.restoration.

An ecological description An ecological description of the reference (see page of the reference (see page 8 of PRIMMER multiple 8 of PRIMMER multiple sites).sites).

Comparison (Cont.)Comparison (Cont.)

Developing Developing AlternativesAlternativesDocumenting Documenting DecisionsDecisions

Explain integration Explain integration with landscape and with landscape and its flows of organisms its flows of organisms and materials.and materials.Explicit plans, Explicit plans, schedules, and schedules, and budgets for site budgets for site preparation, preparation, installation and post installation and post installation activities, installation activities, including a strategy including a strategy for making prompt for making prompt midmid--course course corrections.corrections.

Comparison (CONT.)Comparison (CONT.)

Developing Developing AlternativesAlternativesDocumenting Documenting DecisionsDecisions

Strategies for longStrategies for long--term protection term protection and maintenance and maintenance of the restored of the restored ecosystem.ecosystem.

Comparison (Cont.)Comparison (Cont.)

Establish Funding Establish Funding and and EnvEnv. Clearance. ClearanceImplementationImplementationMonitoringMonitoring

Well developed and Well developed and explicitly stated explicitly stated performance performance standards, with standards, with monitoring monitoring protocols by which protocols by which the projects can be the projects can be evaluated.evaluated.

Workshop FocusWorkshop Focus

Physical AssessmentPhysical AssessmentOverlap to Biological AssOverlap to Biological Assessment essment EEspecially for specially for Riparian Area and Riparian Area and PoolsPoolsOverlap to Water Quality EsOverlap to Water Quality EspeciallypeciallyDuring ConstructionDuring Construction

Precursors to Streambank Precursors to Streambank Accelerated ErosionAccelerated Erosion

Watershed Level ConditionsWatershed Level ConditionsReach Level ConditionsReach Level Conditions

Watershed PrecursorsWatershed PrecursorsExcess Sediment Supply, Especially from Excess Sediment Supply, Especially from Landslides, Debris Flow & Debris Torrents Landslides, Debris Flow & Debris Torrents (Tillamook Co. Oregon example)(Tillamook Co. Oregon example)Increased Roads, Railroads, & CulvertsIncreased Roads, Railroads, & CulvertsDecreased CoverDecreased CoverIncreased Discharge Per Unit AreaIncreased Discharge Per Unit AreaLarge storms (precipitation and duration)Large storms (precipitation and duration)Rain on snow and frozen soilRain on snow and frozen soilIncreased precipitation from storm stallingIncreased precipitation from storm stallingClimate Change Issues Impacting RunoffClimate Change Issues Impacting Runoff

Dynamic EquilibriumDynamic Equilibrium Problem of Excess SupplyProblem of Excess Supply

E.W. Lane, 1955

W/S Excess Sediment SupplyW/S Excess Sediment Supply DefinitionsDefinitions

LANDSLIDELANDSLIDE----The movement of a mass of The movement of a mass of rock, debris, or earth down a slope.rock, debris, or earth down a slope.DEBRIS FLOWDEBRIS FLOW----Landslides where a Landslides where a considerable amount of coarse material considerable amount of coarse material are suddenly moved by an excessive are suddenly moved by an excessive amount of water and transported in an amount of water and transported in an extremely fast and destructive flow extremely fast and destructive flow through a valley. through a valley. DEBRIS TORRENTDEBRIS TORRENT---- Debris torrents are Debris torrents are rapid movements of water charged debris rapid movements of water charged debris that are confined to steep headwater that are confined to steep headwater channels.channels.

2004 Landslide2004 Landslide--Debris FlowDebris Flow-- Debris TorrentDebris Torrent

Study during 1996Study during 1996--1997 flood season 1997 flood season found 9,582 landslides of all typesfound 9,582 landslides of all typesTillamook County accounted for 836 in the Tillamook County accounted for 836 in the inventory of which 212 were in the Wilson inventory of which 212 were in the Wilson River Watershed and 159 in the Kilchis River Watershed and 159 in the Kilchis River WatershedRiver WatershedThe Little South Fork of The Little South Fork of Kilchis River had a typical landslideKilchis River had a typical landslide--debris debris flowflow-- debris torrent in December 2003debris torrent in December 2003

Landslide and Debris FlowLandslide and Debris Flow

Landslide HeadwallLandslide Headwall SpheroidalSpheroidal WeatheringWeathering

Residual AfterResidual After Slurry Like Debris FlowSlurry Like Debris Flow

Start of Debris TorrentStart of Debris Torrent Debris Flow Washed OutDebris Flow Washed Out

Upstream at Start of Debris Upstream at Start of Debris Torrent See Rounded BoulderTorrent See Rounded Boulder

>>500 feet from Source500 feet from Source

Downstream of Debris TorrentDownstream of Debris Torrent & Residual Rounded Boulders & Residual Rounded Boulders

Down Debris TorrentDown Debris Torrent

Debris Flow and Torrent Debris Flow and Torrent Deposition on RoadDeposition on Road

Offsite EffectsOffsite Effects

35,000 cubic yards of landslide35,000 cubic yards of landslide--debris flowdebris flow--debris torrentdebris torrent800 cubic yards into South Fork of 800 cubic yards into South Fork of KilchisKilchisThis sediment moves downstream in This sediment moves downstream in pulsespulsesChinook spawning Chinook spawning reddsredds impactedimpacted

Reach Level PrecursorsReach Level PrecursorsGeometry Alteration ( Walla Walla River Geometry Alteration ( Walla Walla River straightening example)straightening example)Streambed Alteration (bed excavation like Streambed Alteration (bed excavation like under bridges example Mill Creek Salem ) under bridges example Mill Creek Salem ) Creating HeadcutsCreating HeadcutsRemoval of Native Vegetation (physical, Removal of Native Vegetation (physical, overgrazing, and biological like willow overgrazing, and biological like willow borer)borer)Flow Peak and Duration Increase (cyclic as Flow Peak and Duration Increase (cyclic as well as climate change)well as climate change)

Walla Walla River,WA LookingWalla Walla River,WA Looking Downstream PreDownstream Pre--19641964

ChannelizationChannelization

football field & track

Walla Walla River, WAWalla Walla River, WA December 1964 December 1964 -- January 1965January 1965

Walla Walla Looking Walla Walla Looking UpstUpst. Dec. . Dec. 1964 1964 -- Jan. 1965Jan. 1965

Dynamic Dynamic EquiibriumEquiibrium Modified By Modified By

ChannelizationChannelization Qs=Sediment discharge (especially bedQs=Sediment discharge (especially bed--material load), material load),

DD5050 = Particle Size, = Particle Size, QQww = Flow, S = Stream Slope= Flow, S = Stream Slope

Walla Walla River, WAWalla Walla River, WA December 1964 December 1964 -- January 1965January 1965

DownDown--cutting & Widening for Load, & Meandering for cutting & Widening for Load, & Meandering for Slope, areSlope, are

the Negative Feedback Mechanism the Negative Feedback Mechanism to Return to to Return to Dynamic EquilibriumDynamic Equilibrium

Trout Cr. Deschutes,Co. Trying Trout Cr. Deschutes,Co. Trying to Return to Dyn. to Return to Dyn. EquilEquil..

Mill Cr. Gravel Removed Under Mill Cr. Gravel Removed Under Bridge (initiating downcutting by Bridge (initiating downcutting by excavation verses slope caused excavation verses slope caused

like in Walla Walla River)like in Walla Walla River)

At Winter Street 1927 DrawingAt Winter Street 1927 DrawingSee Upstream EffectsSee Upstream Effects

Mill Creek at WinterMill Creek at WinterBridge x-sect.

Mill Creek, Salem Mill Creek, Salem (upstream (upstream at Summer St.) Wanted to at Summer St.) Wanted to

Remove Deposition BarRemove Deposition Bar

Mill Creek SalemMill Creek Salem

Mill Creek Salem Mill Creek Salem

Mill Creek DrawingMill Creek Drawing

Mill Creek Downcutting Along Mill Creek Downcutting Along Wall Downstream of CapitolWall Downstream of Capitol (used to justify bank work) (used to justify bank work)

Mill Cr. Island is a Remnant of Mill Cr. Island is a Remnant of 1928 Streambed (upstream 1928 Streambed (upstream

from 17th St) from 17th St)

Remnant of BedRemnant of Bed Upstream of Upstream of ChemeketaChemeketa StSt

Mill Cr. Headcut to Check Dam Mill Cr. Headcut to Check Dam (1930 diver. to Mill Race)(1930 diver. to Mill Race)

What Are Reach Causes of What Are Reach Causes of Streambank ErosionStreambank Erosion

The reach causes are a combination The reach causes are a combination of fluvial processes, mass failure of fluvial processes, mass failure factors, vegetation factors, biological factors, vegetation factors, biological factors flow factors, and climate factors flow factors, and climate factors factors

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