Overview of ExerciseOverview of Exercise

Module 1 – Geologic Setting Module 1 – Geologic Setting

Module 2 – Flow RegimesModule 2 – Flow Regimes

Module 3 – Downstream EffectsModule 3 – Downstream Effects

Module 1 – Geologic SettingModule 1 – Geologic Setting

Goals – Goals –

Based on topography and geology, Based on topography and geology, delineate reaches and dams that are likely delineate reaches and dams that are likely to have similar downstream issues.to have similar downstream issues.

Module 1 – Geologic SettingModule 1 – Geologic SettingData OverviewData Overview

Reach MapReach Map

Topographic MapTopographic Map

Geologic MapGeologic Map

Longitudinal ProfilesLongitudinal Profiles

Table Of Dam InformationTable Of Dam Information

Historic Event ChronologyHistoric Event Chronology

What Did You Learn?What Did You Learn?

What Characteristics Did You Base Your What Characteristics Did You Base Your Reach Delineation On? Are These Likely Reach Delineation On? Are These Likely To Be The Same For Another River?To Be The Same For Another River?Based On Where Each Dam Is Located, Based On Where Each Dam Is Located, Do You Expect Them To Affect The River Do You Expect Them To Affect The River Downstream In Similar Ways?Downstream In Similar Ways?Which Reservoirs Are Likely To Have The Which Reservoirs Are Likely To Have The Greatest Rates Of Sediment Greatest Rates Of Sediment Accumulation?Accumulation?

Module 1 SummaryModule 1 Summary

The Geologic Setting And Geomorphic The Geologic Setting And Geomorphic History Of Each Dam is Unique. Therefore History Of Each Dam is Unique. Therefore

Dam Effects Must Be Evaluated And Dam Effects Must Be Evaluated And Viewed Within The Larger Geologic Viewed Within The Larger Geologic

Context.Context.

Module 2 – Flow RegimesModule 2 – Flow Regimes

Goals –Goals –

Determine how dams have affected the Determine how dams have affected the flow regime of the Clackamas River.flow regime of the Clackamas River.

Module 2 – Flow RegimesModule 2 – Flow RegimesData OverviewData Overview

Plumbing Schematic / USGS Site ListPlumbing Schematic / USGS Site List

Discharge Discharge

Peak Flow Peak Flow

Flow Duration Flow Duration

Oak Grove HydrographsOak Grove Hydrographs

What Did You Learn?What Did You Learn?

Do All The Dam-Imposed Changes In Do All The Dam-Imposed Changes In Flow Regime Result In Geomorphic Flow Regime Result In Geomorphic Change?Change?

How Different Is The Predicted How Different Is The Predicted Geomorphic Change Below Each Of The Geomorphic Change Below Each Of The Dams?Dams?

Module 2 SummaryModule 2 Summary

Within The Same Basin, Some Dams Do Within The Same Basin, Some Dams Do Not Significantly Alter Flow Regimes, Not Significantly Alter Flow Regimes,

While Others May Result In Measurable While Others May Result In Measurable Hydrologic Changes. Such Changes May Hydrologic Changes. Such Changes May

Have Different Geomorphic Have Different Geomorphic Consequences Downstream.Consequences Downstream.

Module 3 – Downstream EffectsModule 3 – Downstream Effects

GoalsGoals

Synthesize geologic, hydrologic, and Synthesize geologic, hydrologic, and topographic information to generate likely topographic information to generate likely key issues and recommend studies to key issues and recommend studies to resolve those issues.resolve those issues.

Module 3 – Downstream Effects Module 3 – Downstream Effects Data OverviewData Overview

Reservoir Sediment DataReservoir Sediment Data

North Fork / Faraday DataNorth Fork / Faraday Data

Harriet DataHarriet Data

River Mill DataRiver Mill Data

Identification of StudiesIdentification of Studies

Determining ImportanceDetermining Importance

Allocation of FundingAllocation of Funding

By Using Aerial Photos and By Using Aerial Photos and Sediment Trap Data:Sediment Trap Data:

(Previous Slides)(Previous Slides)

Identify Downstream Effects From Each Identify Downstream Effects From Each DamDam

Predict Likely Channel ChangesPredict Likely Channel Changes

Record ObservationsRecord Observations

By Using Aerial Photos and By Using Aerial Photos and Sediment Trap Data:Sediment Trap Data:

Determine The Relative Importance of Determine The Relative Importance of Each StudyEach Study

Determine Where to Allocate FundingDetermine Where to Allocate Funding

What Did You Learn?What Did You Learn?

Is It Important To Evaluate All Possible Is It Important To Evaluate All Possible Effects?Effects?

Will Every Group Involved Rank The Will Every Group Involved Rank The Potential Effects The Same?Potential Effects The Same?

Module 3 SummaryModule 3 Summary

Downstream effects and related impacts of Downstream effects and related impacts of dams are related to dam type, operating dams are related to dam type, operating

rules, and geomorphic / geologic settings. rules, and geomorphic / geologic settings. Understanding the relative importance of Understanding the relative importance of

each effect allows appropriate studies and each effect allows appropriate studies and research goals to be identified.research goals to be identified.