Analysis Of Level Of Analysis: Study Designs For Dam...

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Analysis Of Level Of Analysis: Study Designs For Dam Removal Monitoring

(in 20 minutes or less)

Desiree Tullos, George Pess,

Kelly Kibler, Mike McHenry

RRNW, February 2009

Types of monitoring1. Regulatory

2. Effectiveness

3. Research and river management

Focusing on research: The acid test

Conceptual Recovery

Knighton 1998

• Rates, patterns, extent

• Linking abiotic and biotic recovery

• Mechanisms of recovery– Movement of bed sediments– Change in food web– Habitat and refugia– Thermal regime

Dam removal to inform river management

Cui et al. (2008)

Presentation overviewLearning from dam removals

Unique learning

opportunity

Adequate funding

Rigorous study design

Prioritized monitoring

Rigorous study designs: Primary challenges

– Identifying and defining control

– Removal timelines

– Number and location of samples needed

– Mixed methods

Underwood 1994

Rigorous study design

Overcoming challenges: Principles for study “rigor”

1. Improve sampling design through definition of “impact” and explicit accounting of natural variation

2. Define objective rules for assessing uncertainty in the results

3. Standardization of data formats

4. Articulation of analytical models, underlying assumptions, and study deviations

Principle 1: Defining impact

1. Conceptualization: Potential outcomes and driving processes

2. Baseline assessment to focus study• Establishes common

set of data

• Identifies unique aspects worth studying

Pizutto 2002

Principle 1: Considering variability

Power analysis: 1-

Effect size Variability Number of samplesSignificance level Model

Principle 2: Reducing uncertainty

• Responsive to dam removal

• Easy to measure

• Low natural variability

0 5 10 15 20 25

Mean Substrate dia.

% Canopy Density

Residual Pool Area

% Sand + Fines

Bed Stability

Riparian Agr.

% Undercut Bank (visual)

% Pool Habitat (visual)

"RBP" Habitat Score

Signal:Noise Ratio(ratio of between-site variance/within-site variance)

EM

AP

-U

SE

PA

20

03

Principle 2: “Significance” isn’t only a statistical concept

• Statistics – Are observed changes outside natural variability of the system?

• Practicality – Are observed changes beyond our ability to measure them?

• Ecology – Are observed changes relevant to the ecosystem?

Principle 4: Deviations from study design

Bad timing

Humility

Inadequate resources

Optimization: designing for efficiency

Opportunistic learning at 2 case studies:

Brownsville and Elwha dam removals

Unique learning

opportunity

Brownsville Dam removal

Brownsville DamRiver: CalapooiaHeight: 5’Purpose: mill diversion, estheticsConstructed: 1960’sRemoval: 2007

Unique learning

opportunity

As a small case study, tests our limits of detection.

Conceptualization and hypothesis development

Conceptual model: Dam traps ~1.5 years of coarse sediment that will be released with dam removal

Baseline Assessment

1. Sediment Release Scenario– Volume of sediment stored =14,000cy, D50 = 59mm

– 1.5 years of sediment at normal winter flows

2. Downstream geomorphology– Response areas and types (Channel units, Bed material, Stream power and

channel competence calculations, review of historical aerial photos)

3. Sensitivity of downstream habitat and ecology– Characterized aquatic habitat, sampled benthic macroinvertebrates

Study Design: “controlled”

Practical Significance: Channel change

1250 1500 1750 2000

US

Aerial photos Field Surveys

DS1 to DS2 Dam

Reach Average Total Aerial Error Reach Average Total Field Error

-75

-60

-45

-30

-15

0

15

30

45

-1500 -1250 -1000 -750 -500 -250 0Ch

an

ge

in b

ar

wid

th a

t c

ros

s s

ec

tio

ns

(m

)

DS2 DS1 Dam

Distance from dam (m)

Ecological Significance: Grain size

DS1-Bar1US mean

-10.0

-5.0

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

1

D5

0 (

mm

)

Brownsville Dam Removal: Monitoring Sites

DS1 surface

DS1 subsurface

US surface

US subsurface

Steelhead spawning preference

Opportunistic Learning: Correcting conceptual models

2319.7

5.7

40

2427.4

0

5

10

15

20

25

30

35

40

45

50

Gr

ain

siz

e (

mm

)

Bars D50

Reach Pools2007 Pools08 Riffles07 Riffles08US 3 4 3 4DS1 1 3 3 4DS2 4 4 2 2

Lateral Pool

Lateral Pool

Riffle

RiffleGlide

GlideRiffle

RiffleGlide

Trench PoolRiffle

Riffle

Glide

Lateral Pool

Riffle

Glide

0

100

200

300

400

500

600

700

800

2007 2008

Le

ng

th (

m)

44.8

53.4

23.0

65.8

28.0

45.2

05

1015202530354045505560657075

Gr

ain

siz

e (

mm

)

Riffles D50

Opportunistic Learning: Investigating detectability

Many changes were within bounds of natural variability and bounds of measurement error

0

5

10

15

20

25

30

35

40

45

19

94

-1995

19

95

-1996

19

96

-1998

19

98

-2000

20

00

-2003

20

03

-2004

20

04

-2005

20

05

-2006

4/2

00

0-7

/2000

Field

Su

rvey

s

19

94

-1995

19

95

-1996

19

96

-1998

19

98

-2000

20

00

-2003

20

03

-2004

20

04

-2005

20

05

-2006

4/2

00

0-7

/2000

Field

Su

rvey

s

19

94

-1995

19

95

-1996

19

96

-1998

19

98

-2000

20

00

-2003

20

03

-2004

20

04

-2005

20

05

-2006

4/2

00

0-7

/2000

Field

Su

rvey

sT

ota

l Err

or

(m)

Average Total Identification Error (m) AverageTotal Position Error (m) Average Wetted Boundary Datum Error (m)

Change in Bar Width Change in Wetted Width Change in Wetted Width

Midpoint

Elwha dam removals

Elwha and Glines Canyon DamsRiver: ElwhaHeight: 108’ and 210’Purpose: hydropowerConstructed: 1913 and 1927Removal: 2012??

90%90 years

Conceptualization and hypothesis development

Conceptual Model: Removal of Elwha dams will promote the re-establishment of self-sustaining

anadromous salmonidpopulations within one to five

generations (2–30 yr) following dam removal

Unique learning

opportunity

Conceptualization and hypothesis development

Wo

od

wa

rd e

t a

l. 2

00

8

Baseline Assessment

1. Sediment Release Scenario– Volume of sediment stored =14,000,000 cy, coarse material

– 2-5 years of elevated sediment loads

2. Downstream geomorphology– Response areas and types (Channel units and floodplain channels, bed

material, review of historical aerial photos)

3. Sensitivity of downstream habitat and ecology– Aquatic habitat, periphyton, benthic macroinvertebrates, fisheries

Study design: “controlled”

Lower

Middle

Upper

Quinault

Sediment

Fish

Yes

Yes

No

No

Statistical significance

McH

enry

an

d P

ess

20

08

Practical significance

Assumption

Recovery rates of salmon are steady state and immediate following dam removal

Uncertainty

• Dam removal may initially cause populations to decline in short term

• Recolonization into some areas may take longer than expected

• Unanticipated barriers to migration may emerge

• Recolonization rates my change

McHenry and Pess 2008

Closing remarks

• Be smart about our analysis and detailed about our questions and hypotheses –BECAUSE EVERY DAM IS DIFFERENT

• Need baseline assessments and link it back to conceptual models

• Always consider and address your uncertainties – errors and stat. power

• Balance your statistics with your ecological significance

• Prioritize monitoring

Unique learning

opportunity

Adequate funding

Rigorous study design

Prioritized monitoring

Yes, every dam is differentBut…general process is the same

Acknowledgements

OSU InvestigatorsCara Walter, Jack Zunka, Trent Carmichael, and an army of undergrads

NWFSC InvestigatorsWatershed Program (EC) – Beechie, Coe, Kloehn, Kiffney, Liermann, Morley, Pess

Genetics & Evolution (CB) - Gary Winans

Estuarine & Ocean Ecology (FE) - Kurt Fresh

Migrational Behavior (FE) - Brian Burke, Kinsey Frick

CollaboratorsLower Elwha Tribe- Larry Ward, Doug Morrill, Mel Elofson, Sonny Sampson, Raymond Moses

NPS - Brian Winter, Jerry Freilich, Steve Acker, Pat Crain, Sam Brenkman

Bureau of Reclamation – Tim Randle

U.S. Fish & Wildlife Service - Roger Peters, Bob Wunderlich

U.S. Geological Survey - Jeff Duda, Pat Shafroth, Chris Konrad, Dave Woodson

University of Idaho - Chris Peery, Nancy Wright, Jeff Braatne

University of Washington - Bob Naiman, Tom Quinn

Peninsula College - Bill Eaton, Jack Ganzhorn, Dwight Barry

Western Washington University - Jim Allaway

University of Montana - Mark Lorang, Ric Hauer

WDFW - Anne Schaffer, Bill Freymond

SupportNOAA Fisheries – NWFSC

NOAA Fisheries – Restoration Center

NOAA – Open Rivers Initiative

USFWS – Coastal Puget Sound Program

USGS

National Fish and Wildlife Foundation

Oregon Watershed Enhancement Board